BIOSYSTEMATICS OF CHIRONOMIDAE (DIPTERA)

INHABITING SELECTED PRAIRIE PONDS IN SASKATCHEWAN

A thesis

Submitted to the Faculty of Graduate Studies

in Partial Fulfillment of the Requirements

for the Degree of

Master's of Science

in the Department of Biology

University of Saskatchewan

by

Dale Wilbert Parker

Saskatoon, Saskatchewan

December 1985

The author claims copyright. Use shall not be made of the

material contained herein without proper acknowledgement, as

indicated on the following page.

,

f

I

«

,""0

•

c0

0..

� �

. " •

# " ..

•f •

t I

r

,.

..'

UNIVERSITY OF SASKATCHEWAN

�: OF GRADUATE STUDIES ArID RESEARCH

Saskatoon

,.

CERnFICATlor� OF THESIS' HORK

..

We .. the undersigned, certify that---------------------------------

Dale Wilbert PAllEa

( full name) . (degrees). candidate for the degree of MASua 0" seIDCB

-------------------------------------

: has presented his thesis with the follow1ng title.

.

. --------------

Bio.,.t... ti�. of Cbironoaidae (Diptera) inhabitinl .elected prairie pond.

in Sa.katcbevan.

(as it appears on title page of thesis)

�h�.�_ the thesis is acceptable in form arid' content, and that a satisfactory

knowledge of the field covered by the thesis wa� demonstrated by the•

candidate through an oral examination held on ·"rid.,. Dece.b�r 13. 1985 •

•

External Examinerc> z'!?�q.dDr. L. Burle••

Internal

•

,Date '. DlC_IHIl"\3. 1985

------ --- .- ----'"--

The author has agreed that the Library, University of

Saskatchewan, may make this thesis freely available for

inspection. Moreover, the 'author has agreed that permission

for extensive copying of this thesis for scholarly purposes

may be granted by the professor or professors who supervised

the thesis work herein or, in their absence, by the Head of

the Department or the Dean of the Gollege in which the thesis

work was done. It is understood that due recognition will be

given to the author of this thesis and to the University of

Saskatchewan in any use of the material in this thesis.

Copying or publication or any other use of the thesis for

financial gain without approval by the University of

Saskatchewan and the author's written permission is

prohibited.

Requests for permission to copy or make other use of

material in this thesis in whole or in part should be

addressed to:

Head of the Department of Biology

University of Saskatchewan

SASKATOON, Saskatchewan, Canada

S7N CWO

i

ABSTRACT

Thirty-six species of Chironomidae from a single

semipermanent pond near Floral Saskatchewan and four species

from other ponds were collected in the study. Seven species

and five genera were not previously recorded from

Saskatchewan ponds.

Identification keys to genera .and species are provided.

For each genus, diagnoses of larval and pupal stages are

provided as well as a taxonomic, biological and

distributional distributional. For each species,

descriptions of the immature stages collected are provided

along with taxonomic remarks, biological notes and

distribution.

Pond habitats and classification systems are described

and discussed. Chironomid communities are discussed in

relation to pond types, and difficulties of working with

Chironomidae are presented.

Water depth and water and air temperatures are given for

selected dates for the primary study pond. Effects of flood

conditions on the pond chironomid community are presented

discussed.

ii

ACKNOWLEDGEMENTS

I wish to thank my supervisor Dr. O. M. Lehmkuhl for

accepting me as his graduate student. He provided lab space,

research funding, and many helpful suggestions throughout the

course of the study. I also thank him for allowing me the

freedom to learn on my own.

I also wish to thank Peter Mason for his taxonomic help

and for many useful discussions we have had on chironomids

and other subjects.

I would like to thank Dr. D. R. Oliver, M. E. Dillion,

and B. Bilyj for verifying my identifications and making many

valuable comments about my slides.

Thanks are due to the people I shared the laboratory'with

during my study: Lloyd Oosdall, Blair �arvis, Douglas Smith

. and Eric Whiting. They all provided support and many

enjoyable hours of discussion on a wide range of topics.

Thanks to Dennis Dyck for his assistance with the

photographic plates.

I would also like to thank my brother, James Parker, for

flying over pond A so I could take aerial· photographs.

Special thanks -to Vicki Keeler for assisting me on many

field trips and helping me with the photography, in

particular for allowing me to use her photograph for the

frontispiece. I would also like to thank her for her support

during most of the thesis.

Finally I wish to thank my parents, Bert and Margaret

Parker, for their patience and constant support during this

study and my previous studies.

iii

TABLE OF CONTENTS

ABSTRACT ••••••••••••••••••••••••••••••••••••••••••••••1

ACKNOWLEDGEMENTS ••••••••••••••••••••••••••••••••••••• ii

TABLE OF CONTENTS ••••••••••••••••••••••••••••••••••• iii

LIST OF TABLES ••••••••••••••••••••••••••••••••••••••• vi

LIST OF FIGURES ••••••••••••••••••••••••••••••••••••• vii

INTRODUCTION •••••••••••••••••••••••••••••••••••••••••• 1

POND ECOLOGY •••••••••••••••••••••••••••••••••••••••••• 2

a. Temporary ponds ••••••••••••••••••••••••••••••

·

••••• 5

b. Semipermanent ponds ••••••••••••••••••••••••••••••• 9

c. Permanent ponds •••••••••••••• � ••••••

·

••••••••••••• 10

d. Aestival ponds •••••••••••••••••••••••••••••••••• 11

INTRODUCTION TO CHIRONOMIDAE ••••••••••••••••••••••••• 12

a. Chironomidae life histories •••••••••••••••••••••• 15

b. Difficulties studying Chironomidae ••••••••••••••• 20

c. Pond Chironomidae •••••••••••••••••••••••••••••••• 23

STUDY SITES •••••••••••••••••••••••••••••••••••••••••• 27

MATERIALS AND METHODS •••••••••••••••••• • • • • • • • • • • •••• 29

a. Sample collection •••••••••••••••••••••••••••••••• 29

b. Environmental information •••••••••••••••••••••••• 30

c. Rearing •••••••••••••••••••••••••••••••••••••••••• 31

d. Slide preparation •••••••••••••••••••••••••••••••• 31

e. Illustration methods ••••••••••••••••••••••••••••• 34

VERIFICATION AND DISPOSITION OF SPECIMENS •••••••••••• 34

INTRODUCTION TO BIOSYSTEMATICS SECTION ••••••••••••••• 35

iv

a. Family terminology ••••••••••••••••••••••••••••••• 36

b. Measurements and ratios •••••••••••••••••••••••••• 39

KEY TO SUBFAMILIES ••••••••••••••••••••••••••••••••••• 40

SUBFAMILY TANYPODINAE

a. Subfamily diagnosis •••••••••••••••••••••••••••••• 41

b. Larval and pupal keys •••••••••••••••••••••••••••• 42

c. Genus Ablabesmyia Johannsen •••••••••••••••••••••• 43

d. Genus Derotanypus Roback ••••••••••••••••••••••••• 47

e. Genus Procladius Skuse ••••••••••••••••••••••••••• 50

f. Genus Psectrotanypus Kieffer ••••••••••••••••••••• 55

g. Genus Tanypus Maigen ••••••••••••••••••••••••••••• 58

SUBFAMILY CHIRONOMINAE

a. Subfamily diagnosis •••••••••••••••••••••••••••••• 62

b. Larval and pupal keys •••••••••••••••••••••••••••• 64

c. Genus fbironomu1 Meigen •••••••••••••• � ••••••••••• 67

d. Genus Cladopelma Kieffer ••••••••••••••••••••••••• 77

e. Genus f!yptochironomu1 Kieffer ••••••••••••••••••• 81

f. Genus Dicrotendi� Ki�ffer •••••••••••••••••••••• 84

g. Genus Einfeldia Kieffer •••••••••••••••••••••••••• 86

h. Genus Endochironomus Kieffer ••••••••••••••••••••• 89

i. Genus Glyptotendipes Kieffer ••••••••••••••••••••• 93

j. Genus Parachironomus Lenz •••••••••••••••••••••••• 98

k. Genus Phaenopse� Kieffer ••••••••••••••••••••• 102

1. Genus Cladotanytars� Kieffer ••••••••••••••••••• 10S

m. Genus Paratanytar�1 Bause •••••••••••••••••••••• 107

n. Genus Tanytarsus van der Wulp ••••••••••••••••••• 109

-

v

SUBFAMILY OTHOCLADIINAE

a. Subfamily diagnosis. • • • • • • • • • • • • • • • • • • • • •••••••• 11 6

b. Larval and pupal keys •••••••••••••••••••••••• � •• 117

c. Genus Acricotop� Kieffer ••••••••••••••••••••••• 119

d. Genus .£2!ynonet..ira Winnertz •••••••••••••••••••••• 122

e. Genus Cricotopus van der Wulp ••••••••••••••••••• 125

f. Genus Hydrobae� Fries ••••••••••••••••••••••••• 130

g. Genus bimnophyes Eaton •••••••••••••••••••••••••• 134

h. Genus Psectocladi� Kieffer ••••••••••••••••••••• 136

i. Genus Pseudosmittia Goetghebuer ••••••••••••••••• 143

ADDITIONAL RESULTS AND DISCUSSION

a. Temperature ••••••••••••••••••••••••••••••••••••• 146

b. Water depth •••••••••••••••••••••••••••••••• ; •••• 146

c. Microhabitats in Pond A ••••••••••••••••••••••••• 14B

d. Feeding ••••••••••••••••••••••••••••••••••••••••• 149

e. Emergence ••••••••••••••••••••••••••••••••••••••• 150

f. New records of Saskatchewan pond Chironomidae ••• 151

SUMMARY ••••••••••••••• . . . . . . . . . . . . . . . . . . . . . . . . • ••••• 152

CONCLUSION •••••••••• . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . •• 153

LITERATURE CITED •••••••••••••••••••••••••••••••••••• 155

FIGURES ••••••••••••••••••••••••••••••••••••••••••••• 171

TABLES •••••••••••••••••••••••••••••••••••••••••••••• 255

•

vi

LIST OF TABLES

Table 1: Air and Water temperatures for pond A ••••• 255

Table 2: Chironomid species list ••••••••••••••••• ••257

•

Figure 1:

Figure 2:

Figure 3:

Figure 4:

Figure 5:

Figure 6:

Figure "7:

Figure 8:

vii

LIST OF FIGURES

Map of pond A ••••••••••••••••••••••••• 171

Microscope slide showing positions of

a reared specimen.................... 172

Lateral view of larva� ••••••••••••••• 173

174Ventral view of tanypod head capsule.

Ventral view of 'a Chironominae,

head capsule ••••••••••••••••••••••••••• 174

Ventral view of pupal cephalothorax.. 175

Dorsal view of pupal abdomen......... 175

�blabesmyia pulchripennis larval

antenna.............................. 176

Ablabesmyia pulchripennis larval

hypopharyngis, paraligula and ligula.

Figure 10: Ablabesmyia pulchripennis larval

Figure 9:

176

mandible............................. 176

Figure 11: Ablabesmyia pulchripennis larval

maxillary palp ••••• �................. 176

Figure 12: Ablabesmyia pulchripennis pupal

anal lobes........................... 176

Figure 13: Ablabesmyia pulchri�ennis

thoracic horns and thoraxkamm........ 178

Figure 14: Ablabesmyia pulchripennis pupal

abdominal tergites I to IV........... 178

Figure 15: Ablabesmyia pulchripennis pupal

..

viii

abdominal tergites V to VIII and anal

lobes........... ..•..•.. .•••.•.... ... 178

Figure 16: �rotan� �laskensis larval

antennae ••••••• ;..................... 179

Figure 17: Derotanypu� �laskensis larval

hypopharyngis, ligula and paraligula. 179

Figure 18: Derotanypus alaskensis larval

dOFsomentum.......................... 179

Figure 19: Oerotan� �skensis larval

mandible............................. 179

Figure 20: perotanypus alaskensis simple

claw of larval posterior parapod..... 179

Figure 21: Oerotanypus alaskensis arched

claw of larval posterior parapod..... 179

Figure 22: Oerotanyp� alaskensis pupal

thoracic horn........................ 181

Figure 23: Oerotan� alaskensis pupal

abdominal tergites I to IV........... 181

Figure 24: �rotan� alaskensis pupal

abdominal tergites VI to VIII and

anal lobes........................... 181

Figure 25: Procladi�·�.!d.2 larval antenna..... 182

Figure 26: Procladiu� nietus larval para-

ligula and ligula.................... 182

Figure 27: Procladius nietus larval

dorsomentum.......................... 182

.....

ix

Figure 28: Erocl�iu� �iet� larval mandible.... 182

Figure 29: Procla� �� pupal thoracic

horns. • • • • • • • • • • • • • • • • • • • • • . • • • • • • • • • 184

Figure 30: Pro c 1 a .s!l�. niet� pupal abdominal

tergites V to VIII and anal lobes •••• 184

Procladius (Jj) • SPa larval antenna ••• 185

.Erocladiu� (Jj) • Spa larval ligula

Figure 31:

Figure 32:

and paraligula....................... 185

Figure 33: .Erocladius (Jj). SPa larval hypo-

pharyngis ••·•••••••••••••••••••••••••• 185

Figure 34: Procladiu� (Jj). SPa larval dorso-

mentum. • • • • • • • • • • • • • • • • • • • • ... • • • • • • • • 185

Figure 35: Procladius (Jj). SPa larval

mandible............................. 185

Figure 36: Procladiu� (Jj). sp. pupal thoracic

horn'. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 187

Figure 37: Procladius (Jj). SPa pupal

tergites V to VIII and anal lobes.... 187

Figure 38: Psectrotan� ,2yari 'larval

antenna.............................. 188

Figure 39: Esectrotanypus ,2�i larval

dorsomentum, paraligula, ligula and

hypopharyngis........................ 188

Figure 40: Psectrotanypus dyari larval

mandible............................. 188

Figure 41: Psectrotan�pus dyari pupal

..

Figure 42:

Figure 43:

x

thoracic horn........................ 190

Psectrotanypus £lari pupal

abdominal tergites I to V ••••••••••••

Psectrota�� dyarl pupal

abdominal tergites VI to VIII and

190

anal lobes........................... 190

Figure 44: Tan� eunctip�nis larval

antenna.............................. 191

Figure 45: TanYE� £unctipennis larval para-

ligula and ligula.................... 191

Figure 46: �� Eunct1E�nis larval

Figure 47:

Figure 48

Figure 49:

dorsomentum.......................... 191

Tan�pus Eunctieennis larval

mandible............................. 191

Chironomus ��lla larval 51 •••••••••

Chironomus atrella larval ventro-

192

mentum and mentum.................... 192

192·Figure 50: Chironomus atrella larval mandible •••

Figure 51: �ironomus atrella pupal cephalic

Figure 52:

Figure 53:

Figure 54:

tubercle •••••••••••••••••••••••••••• � 192

Chl££D�� atrell� spur on pupal

abdominal segment VIII............... 192

Chl££n�� ripariu� larval

antenna.............................. 193

Chiron�� ripariu� larval mentum

and ventromentum..................... 193

xi

Figure 55: Chl££n�� !iEari�� larval 51....... 193

Figure 56: Chiro�� ripari� larval pecten

epipharyngis......................... 193

Figure 57: Chironom� ripari� larval

mandible............................. 193

Figure 58: Chironomus riparius pupal

cephalic tubercle •••• �............... 193

Figure 59: Chiro�� ripari� spur on pupal

abdominal segment VIII............... 193

Figure 61:

Chiro�� atrella pupal

abdominal tergites II to VI ••••••••••

Chironom� !iparius pupal

abdominal tergites 'III to VI •••••••••

Chironomus tentans larval antenna� •••

Chironomus te�� larval SI •••••••••

Chironomus �ntans larval pecten

195

Figure 60:

Figure 62:

Figure 63:

Figure 64:

195

196

196

epipharyngis.;....................... 196

Figure 65: Chironomus tentans larval pre-

mandible............................. 196

Figure 66: Chironom� tentans larval

mandible............................. 196

Figure 67: Chironom� tenta� larval ventro-

mentum and mentum.................... 196

Figure 68: Chironomus tentans pupal cephalic

tubercle ••·••••••••••••••••••••••••••• 196

Figure 69: Chironom� tent� spur on pupal

xii

abdominal segment VIII............... 196

Figure 70: Chironomus tentans pupal.

abdominal segments III to V.......... 198

Figure 71: Chironomus ten tans pupal

abdominal segments 'VII and VIII and

anal lobes •••••••••••••• � •••••••••••• 198.

Figure 72: Chironomus SPa pupal abdominal

segments III to V.................... 200

Figure 73: Chironomus sp. pupal abdominal

segments VII and VIII................ 200

Figure 74: Cladopelma SPa 1 pupal abdominal

segments............................. 202

Figure 75: Cladopelma sp. 2 larval antenna ••• �.. 203

Figure 76: Cladopelma sp. 2 larval

ventromentum and mentum.............. 203

Figure 77: Cladopelma sp. 2 larval mandible..... 203

Figure 78: Cryptochironomus digitatus larval

antenna ••• � •••••••••• o.�............. 204

Figure 79: Cryptochironrimus digitatus larval

pr�mandible •••••••••••••••••••••• o.o. 204

Figure 80: Cryptochironomus digitatus larval

Figure 81:

ventromentum and mentum ••••••••••••••

Cryptochironomus digitatus larval

204

mandible............................. 204

Figure 82: Cryptochironomus digitatus pupal

cephalic tubercles................... 206

-

xiii .

Figure 83: Cryptochironomus digitatu2 pupal

abdominal segment VIII and anal lobes 206

Figure 84: £!yptochironomus digitatus pupal

abdominal tergites III and IV........ 206

Figure 85: Dicrotendipes sp. larval antenna..... 207

Figure 86: Dicrotendipes sp. larval pecten

epipharyngis ••••••• �............... 207

Figure 87: Dicrotendipes sp. larval

premandible.......................... 207

Figure 88: Dicrotendipes sp. larval ventro-

mentum and mentum•••••••••••••••••••• 207

Figure 89: Dicrotendipes sp. larval mandible •••• 207

Figure 90: Einfeldia sp. larval antenna ••••••••• 208

Figure 91 : Einfeldia sp. larval 5 I •••••••••••••• 208

Figure 92: Einfeldia sp. larval frontal

apotome................................ 208

Figure 93: Einfeldia sp. larval ventromentum

and mentu�........................... 208

Figure 94: £lnfeldia sp. larval mandible........ 208

Figure 95: Einfeldia sp. spur on pupal.

abdominal segment VIII............... 208

Figure 96: Einfeldia sp. pupal

abdominal tergites II to V........... 210

Figure 97: Endochironomus nigricans larval

antenna.............................. 211

Figure 98: Endochironomus nigricans larval

•

xiv

pecten epipharyngis.................. 211

Figure 99: Endochironomus nigricans larval

premandible.......................... 211

Figure 100: Endochironomus nigricans larval

ventromentum......................... 211

Figure 101: Endochironomus nigricans larval

mentum............................... 211

Figure 102: Endochironomus nigricans larval

mandible............................. 211

Figure 103: Endochironomus nigricans pupal

abdominal tergites III to V.......... 213

Figure 104: Endochironomus nigricans pupal

abdominal,tergites VI to VIII and

anal lobes........................... 213

Figure 105: Glyptotendipes barbipes larval

antenna.............................. 214

Figure 106: Glyptotendipes barbip�s larval 51 ••••

Figure 107 : Glyptotendipes barbipes larval

pecten epipharyngis ••••••••••••••••••

Figure 108: Glyptotendipes barbipes larval

ventromentum and mentum ••••••••••••••

Figure 109 : Gl�ptotendipes barbipes larval

214

214

214

mandible............................. 214

Figure 110: Glyptotendipes barbipes pupal

abdominal tergites III to V.......... 216

Figure 111: Glyptotendipes sp. pupal abdominal

xv

tergites III to VI................... 216

Figure 112: Parachironomus SPa 1 pupal

abdominal tergites IV to VIII and

anal lobes........................... 218

Figure 113: Parachironomu� SPa 2 pupal

abdominal tergites V to VIII and anal

lobes................................ 218

Figure 114: Parachironomus SPa 3 larval antenna.. 219

Figure 115:. Parachironomus SPa 3 larval pecten

epipharyngis......................... 219

Figure 116: Parachironomus SPa 3 larval ventro-

mentum and mentum.................... 219

Figure 117: Parachironomu� SPa 3 larval

mandible............................ 219

Figure 118: Phaenopsectra SPa larval antenna..... 220

Figure 119: Phaenopsectra SPa larval pecten

epipharyngis......................... 220

Figure 120: Phaenopsectra �p. larval mentum and

ventromentum......................... 220

Figure 121: Phaenopsectra SPa larval mandible.... 220

Figure 122: Cladotanytarsus SPa larval antenna... 221

Figure 123: Cladotanytars!!2 SPa larva1· 51........ 221

Figure 124: Cladotanytarsus SPa larval pecten

epipharyngis......................... 221

Figure 125: Cladotanyta�!!2 SPa larval mentum

and ventromentum..................... 221

•

xvi

Figure 126: Cladotanyta� SPa larval mandible.. 221

Figure 127: Cladotanytarsus SPa claw on

posterior parapod of larva........... 221

Figure 128: Paratanytarsus Spa larval antenna.... 222

Figure 129: Pa!atanytarsus SPa larval 51......... 222

Figure'130: Paratanytarsus SPa larval

premandible......................... 222

Figure 131: Paratanytarsus SPa larval mentum

and ventromentum..................... 222

Figure 132: Paratanytarsus SPa larval mandible... 222

Figure 133: Tanytarsus SPa 1 pupal

cephalothorax....................... 224

Figure 134: T�nytarsus SPa 1 pupal abdominal •••

tergites III to VIII and anal lobes.. 224

Figure 135: Tanytarsus SPa 2 pupal abdomen....... 226

Figure 136: Tanytarsus SPa 3 larval antenna...... 227

Figure 137: Tanytarsus SPa 3 larval SI............ 227

Figure 138: .Tanytarsus SPa 3 larval pecten

epipharyngis......................... 227

Figure 139: Tanytarsus SPa 3 larval mentum and

ventromentum......................... 227

Figure 140: Tanytarsu� SPa 3. larval mandible..... 227

Figure 141: Acricotopus senex larval antenna..... 228

Figure 142: Acricotopus �� larval SI......... 228

Figure 143: Acricotopus senex larval

premandible.......................... 228

xvii

Figure 144: Acricotopus senex larval mentum

and ventromentum..................... 228

Figure 145: Acricotopus senex larval

mandible............................. 228

Figure 146: Acricotopus senex pupal thoracic

horn ••• �............................. 230

Figure 147: Acricotopus senex pupal abdominal

tergites III to VIII and anal lobes ••

Figure 148: Corynoneura SPa 1 pupal abdominal

tergites III to VIII and anal lobes ••

Figure 149: Corynoneura SPa 2 larval antenna •••••

Figure 150: Corynoneura SPa 2 larval mentum ••••••

Figure 151 : Corynoneura SPa 2 larval mandible ••••

Figure 152: Cor:tnoneura SPa 2 spur on larval

procercus ••••••••••••••••••••••••••••

Figure 153: Cricotopus ornatus larval antenna ••••

Figure 154: Cricotopus ornatus larval 51 •••••••••

Figure 155 : Cricotopus ornatus larval pecten

230

232

233

233

233

233

234

234

epipharyngis......................... 234

Figure 156: Cricotopus ornatus larval

premandible.......................... ·234

·Figure 157: Cricotopus ornatus larval mentum •••••---

Figure 158: Cricotopus ornatus larval

mandible •••••••••••••••••••••••••••••

Figure 159: Cricotopus ornatus L-4 seta on

234

234

larval abdominal segment V........... 234

-

xviii

Figure 160: Cricoto� ornatus pupal thoracic

horn................................. 236

Figure 161: Cricoto� ornatus pupal

abdominal tergites II to VIII and

anal lobes........................... 236

Figure 162: Cricotopus sp. 1 pupal thoracic

horn. • • • • .. • • • • • • • • • • • • • • • • • • • • • • • • • • • 238

Figure 163: Cricotopus sp. 1 pupal abdomen....... 238

Figure 164: Cricatopus sp. 2 pupal thoracic

horn................................. 240

Figure 165 : Cricoto� sp. 2 pupal abdominal

tergites III to VIII and anal lobes •• 240

Figure 166 : Hydrobaenus sp. 2 larval antenna ••••• 241

Figure 167 : Hydrobaenus sp. 2 larval 5 I •••••••••• 241

Figure 168: H�drobaenus sp. 2 larval

premandible.�........................ 241

Figure 169: Hydrobaenus sp. 2 larval mentum and

ventromentum......................... 241

Figure 170: Hydrobaenus sp. 2 larval mandible.... 241

Figure 171: Hydrobaenus· sp. 1 pupal abdominal

tergites III to VIrI and anal lobes�. 243

Figure 172: Limnophyes sp. pupal abdominal

tergites III to VIII and anal lobes.. 243

Figure 173: Esectrocladius flavus larval

antenna.............................. 244

Figure 174: Psectrocladius flavus larval 51...... 244

xix

Figure 175: Psectrocladius !1� larval

premandible •••••••••••••••••••••••••• 244.

Figure 176: Psectrocladius flavus larval

mentum and ventromentum.............. 244

Figure 177: Psectrocladius flavus larval

mandible............................. 244

Figure 178: Psectrocladius flavus spur on

larval procercus..................... 244

Figur. 179: Psectrocladius flavus pupal

thoracic horn........................ 246

Figure 180: Psectrocladius flavus pupal

abdominal tergites II to V •••••••• �.. 246

Figure 181: Psectrocladius flavus pupal

abdominal tergites V to VIII and anal

lobes................................ 246

Figure 182: Psectrocladius sp. 1 larval

antenna.............................. 247

Figure 183: Psectrocladius sp. 1 larval SI....... 247

Figure 184: Psectrocladius sp. 1 larval

premandible.......................... 247

Figure 185: Psectrocladius sp. 1 larval mentum

and ventromentum..................... 247

Figure 186: Psectrocladius sp. 1 larval

mandible............................ 247

Figure 187: Psectrocladius sp. 1 pupal thoracic

horn................................. 249

xx

Figure 188: Psectrocladius sp. 1 pupal

abdominal segments II to VIII and

anal lobes.......................... 249

Figure 189: Psectrocladius sp. 2 pupal thoracic

horns................................. 251

Figure 190: Psectrocladius sp. 2 pupal abominal

tergites II to VIII and anal lobes ••• 251

Figure 191 : Pseudosmittia sp. pupal abdomen •••••• 253

Figure 192 : Graph of water depth in pond A ••••••• 254

..

1

INTRODUCTION

Ponds have received very little attention from the

scientific community. As a result there is a lack of

detailed information on pdnd inhabitants, their life

histories and ecologies and how the pond ecosystem functions

as a whole. Past studies on temporary and semipermanent

ponds have shown them to be different from more permanent

water bodies (Wiggins et ale 1980; Kenk 1949). Temporary and

semipermanent ponds, in �articular, are extreme habitats

which place severe stress on their inhabitants. Organisms

living in these habitats must not only survive the

environmental fluctuations which occur during the wet phase,

but also must adapt to the dry phase of the basin (Wiggins �!

ale 1980; Hartland-Rowe 1966).

The increased ·usage of agricultural chemicals and

destruction of many pond habitats has led environmentalists

and, water fowl management groups to examine the effects of

these practices on pond inhabitants and the environment.

Questions raised by these groups have largely gone unanswered

because most information on pond inhabitants is

supraspecific, leading to incomplete, ambiguous and

inaccurate ecological assessments (Lehmkuhl et �1. 1984).

To fully understand and assess a pond habitat, each

species must be identified and studied in relation to the

physical and chemical parameters of the pond as well as the

2

intraspecific and interspecific interactions occurring

between the organsims within the pond. Studies of this type

will provide accurate and complete assessments of pond

ecosystems and improve predictions made by environmental

impact studies •

.The present study had three objectives: The first was to

review the literature on North American temperate ponds. The

second was to identify Chironomidae inhabiting selected ponds

in Saskatchewan. The third was to provide identification

keys to the larval and pupal stages collected and provide

preliminary biological information.

The underlying theme of this research project was to

provide basic species level taxonomic information for pond

inhabiting Chironomidae to assist future research in pond

ecology.

POND ECOLOGY

Ponds - or marshes, shallow lakes, sloughs, potholes,

buffalo wallows- may be defined as small, shallow, usually

isolated, lentic bodies of water that lack a beach and are

shallow enough that rooted submerged hydrophytes can grow

throughout the basin (Brower and Zar 1984; Thompson �� �1.

1984; Wetzel 1983). In the prairie and parkland region,

ponds form in shallow depressions left behind by the last

glaciation (Mitsch �� �1. 1982). In Saskatchewan, ponds are.

often a major feature of the landscape, reaching densities of

•

3

over SO/square kilometer in some areas (Driver 1977).

Pond basins hold water from a few days to many years. An

important aspect of pond research has been an attempt to

develop a classification system which will predict the

permanence of surface water in pond basins. Such a

classification system would be useful in assessing and

managing water� land and waterfowl resources.

Because water permanence is not strictly related to water

depth and water area (Stewart and Kantrud 1969), a number of

criteria �ave been used to classify ponds� Millar (1973)

used species composition of submerged aq�atic macrophytes.

Vegetation and water chemistry were used by Stewart and

Kantrud (1969). Driver and Peden (1977) developed a

classification based on water chemistry. Driver (1977) found

chironomid diversity could be used as an indicator of pond

permanence.

Each of these classification methods have shortcomings in

their predictive capabilities because the major factors

determining water depth' in a pond is the rate of

precipitation and rate of evaporation (Manson et �1. 1968).

Therefore, predictions on water permanences are similar to

predicting the weather a year in advance. A short period of

very hot, dry weather or a severe rainfall may greatly alter

water permanence and in turn affect the flora and fauna of

the pond.

The following descriptive classification of ponds has

4

been modified from a number of sources (Wiggins et �1. 1980;

Driver 1977; Driver and Peden 1977; Daoorn and Clifford 1974;

Donald 1971).

There are three basic types of ponds: temporary,

semipermanent and permanent, based on the length of time

surface water is present in the basin.

Temporary ponds or pools are those basins which have two

phases; a wet phase which is suitable for aquatic life, and a

dry phase which is more conducive to terrestrial organisms.

The wet phase may last from a few days to a few months, and

the dry phase occurs during the remainder of the year.

Temporary ponds can be divided into two types; temporary

vernal ponds, which have a short spring wet phase, and

temporary autumnal ponds, which have spring and autumn wet

phases (Wiggins et �1. 1980).

Semipermanent ponds contain water for a number ·of years

consecutively but occasionally the basins dry out (Driver and

Peden 1977).

Permanent ponds are depressions which contain water for

25 years or more and essentially never have a dry phase

(Driver 1977).

The fauna of a pond is determined by a number of

interrelated factors that can be summarized into five general

groups: (1) length of wet phase and dry phase; (2) amount

and type of vegetation and its shading efrect; (3) amount and

type of vegetation within the basin and its role in

5

autotrophy, production of detritus and development of

habitats; (4) dissolved ion levels from the surrounding

watershed and (5) seasonal fluctuations in temperature

(Wiggins �! ale 1980; Driver 1977; Hartland-Rowe 1966;

Dickinson 1949).

TEMPORARY PONDS

Temporary vernal ponds have a wet phase of a few weeks to

a few months in the spring and early summer. During the

remainder of the year surface water is absent (Wiggins et ale

1980; Daborn 1976). The characteristic feature of the

temporary vernal pond is the very brief wet phase.

In the Saskatchewan prairies and parklands, basin

vegetation is dominated by plants such as Ca£�� ath�Eod�

Spreng., Scoloch12� fest��� Willd., El�2charis £al�tris

(L.) and Pol�££D� £2��� Mahl. (Driver 1977; Millar 1973).

The basin is surrounded by grasses in the prairies and ringed

by Sali� spp. and E£Eulu� !£��loid�� Micht. in the parkland

(Driver 1977; Daborn 1976; Mozley 1932). The trees provide

shading, allochthonous material and increase the amount of

('

snow caught by the basin during the winter.

In vernal ponds water chemistry varies throughout the wet

phase. Generally there is an inverse relationship between

water levels and conductivity; as water levels decrease

conductivity increases (Driver and Peden 1977; Daborn 1976).

Daborn (1976) found this inverse relationship also valid for

bicarbonate alkalinity, total hardness (Ca hardness/Mg

-

6

hardness) and chlorides. Ions such as sulphates,

orthophosphates, silicates and iron showed no relationship

with evaporation (Daborn 1976). Sulphates increase during

initial filling of the basin in the spring due to

redissolving and oxidation of sulfides left in the basin and

surrounding watershed by the aerobic decay of terrestrial

macrophytes, and later decline due to uptake by the renewed

growth of vegetation within the basin (Daborn 1976).

Water temperature of vernal ponds closely follows that of

the air 'temperature (Daborn 1976). Dry basin temperatures

depend on the amount of shading in summer and snow cover in

winter; the less there is of each, the more extreme and

severe the temperature and the harsher the �abitat.

Temporary autumnal ponds have a wet phase during the

spring and early summer, followed by a short dry phase during

the late summer and early autumn. In late autumn the basins

are partially filled by autumn rainfall and overwinter with

surface water present (Wiggins �1 ale 1980)�

Kenk (1949) studied two temporary autumnal ponds in the

Ann Arbor, Michigan area. The two autumnal ponds had similar

ranges of pH values and temperature as the two permanent

ponds studied. There was a greater variability in dissolved

oxygen levels, low levels of 1.3 to 1.5 p.p.m. occurred in

January and rose slowly until a few weeks before the ponds

dried to values of 9.3 and 8.0 p.p.m •• Alkalinity in the

autumnal ponds was more variable than in the permanent ponds.

.....

7

Fauna of temporary ponds has been divided into four major

categories based on life history strategies (Wiggins et �1.

1980).

Group I organisms have only passive dispersal abilities

and therefore are year round residents of the pond basin.

They are resistant to dessication in some stage of their life

cycle or avoid it by burrowing deep into the substrate. The

group includes species of Turbellaria, Oligochaeta,

Hirudinoidea, Bryozoa, Anonstraca, Conchostraca, Cladocera,

Copepoda, Ostracoda, Amphipoda, Isopoda, and Mollusca.

Group II organisms arrive in the spring and oviposit

before the surface water disappears. The progeny overwinters

in the dry basin as eggs or larvae. This group includes

species of Ephemeroptera, Coleoptera, Trichoptera, Diptera,

and Acari.

Organisms in group III oviposit independently of water.

Eggs are laid in 'the dry basin and overwinter. These

organisms include species of Odonata, Trichoptera, and

Diptera.

Group IV organisms lack drought resistant stages in their

life cycles. They must enter the temporary pond basin when

water is present develop rapidly, matur�··to· adult and leave

the basin before it drys. Most species overwinter in

permanent habitats. This group includes species of the

Odonata, Hemiptera, Coleoptera, Diptera, Acari and

Amphibians.

8

Temporary ponds are harsh habitats, however many

organisms are more abundant in temporary ponds than in more

permanent ponds. There appear to be two reasons for this;

the first is reduced predation pressure and the second is

large amounts of available nutrients reducing food

competition for most of the pond food web (Wiggins et �1.

1980) •

In temporary ponds the dry phase eliminates predatory

fish. This allows increases in the diversity and population

densities of many aquatic insects and crustaceans (Macan

1977; Macan 1966; Kenk 1949). The dry phase also eliminates

or causes emigration of a number of predatory insect species

that are unable �o survive the pond's dry phase or cannot

overwinter in the temporary pond basin. In the spring, these

predators must im�igrate back into the temporary ponds. The

delayed arrival of the predators give overwintering prey

species an opportunity to complete their life cycle and reach

high population levels before the predators arrive (Wiggins

et a L;. 1980).

The second reason for inhabiting temporary ponds is the

large amount of food available to detritivores and filter

feeders (Wiggins �! �1 1980). 8arlocher�! �1. (1978) found

the protein level in detritus from temporary vernal ponds was

much higher than detritus from temporary autumnal ponds or

permanent ponds. This is due to the terrestrial vegetation

growing in temporary pond basins during the dry phase. When

9

the vegetation dies in the autumn it decomposes aerobically

increasing the amount of decay by fungi and making the

decomposition process more complete (Barlocher �! ale 1978).

When the basin is reflooded the following spring there is a

"pulse" of decomposed plant nutrients available to the

detritivores and the filter feeders. These organsims

increase in number and develop rapidly and in turn provide

abundant food for the immigrating predators.

Reduced food competition and predation pressure for all

trophic levels outweigh the problems of inhabiting temporary

ponds (Wiggins et �1. 1980).

SEMIPERMANENT PONDS

Semipermanent ponds contain water for a number of yea�s

continuously but during periods of drought dry out

completely. Usually during the wet phase the water surface

area is greatly reduced by autumn but does not disappear

completely.

In the parkland semipermanent ponds have a ring of

isolated stands of Sal1� and £�1� (Driver 1977).

Vegetation within the basin is more aquatic than in temporary

ponds, dominated by Scolo.s.bl.2.2, 2.sirp.!d.§, Poto.!!!�lE.!:!, f��,

and Dr��.££l�_giu�.

Driver and Peden (1977) studied the water chemistry of a

semipermanent pond at the end of local groundwater flow.

Groundwater accounted for 95 % of the mineralization of the

pond's water. They found the salinity increased 93 % with a

10

decrease of 16 % in water volume. Precipitation had less of

a diluting effect than it had on temporary ponds. The ionic

hierarchy was continuous from May through August; Mg > Na >

Ca > K and S04 > HC03 > CI. There were steady increases in

magnesium, sodium, and sulphate during the year (Driver and

Peden 1977). Temperature was a function of water depth and

surface area, as the water level decreased water temperature

followed air temperature more closely (Driver and Peden

1977) •

PERMANENT PONDS

Permanent ponds contain water for 25 consecutive years or

more (Driver 1977). Usually the pond has an open water zone

in the central region with submerged and floating hydrophytes

such as �Y!l£Ebyllum spp., E����� richa£dsoni (Benn.)

and b�� trisulc�� (L.) growing in it. The peripheral

regions of the pond are c.haracterized by stands of l.Y£ha

1.§.Ei foll.§ L., 2ci££� .§.£!:!tu_2 Mahl. and .§.£olocblo.§ f� tu.£.2�'§

Willd. (D�iver 1977; Driver and Peden 1977; Stewart and

Kantrud 1969).

Permanent ponds are less variable than temporary ponds in

respect to pH, dissolved oxygen, and alkalinity (Kenk 1949).

Salinity also fluctuates less (Driver and Peden 1977). The

ionic hierarchy of a permanent pond in the Floral area was Ca

> Mg > Na > K and HC03 > S04 > CI (Driver and Peden 1977).

Organisms from all four groups described by Wiggins �.E

.§1. (1980) are able to survive in the permanent pond habitat.

12

overwintering in the wet phase which are completely frozen

and those which are not. If a pond freezes completely to the

bottom, it is termed an aestival pond (Daborn 1974).

Aestival ponds are considered to be temporary ponds by

some researchers because the water·is· unavailable during the

winter (Daborn 1974; Daborn and Clifford 1974). Wiggins et

ale (1980) points out that although the water is in an

unuseable form during ·the winter the organisms are never

exposed to dessiccation and therefore aestival ponds should

be considered as part of permanent water bodies.

Daborn (1974) found several distinguishing biological

features which separate aestival ponds from other lentic

habitats. They have limited primary production, low

phytoplankton population, an unstable fauna and a

vulnerability of the species present to be replaced by

.immigrant species. Daborn (1974) suggests that the flora and·

fauna of a particular year is a "fortuitous assemblage,

determined by the successful immigrants and the remaining

inhabitants of the summer before and the previous winter".

One group of organisms common to all types of ponds is

the Chironomidae (Driver 1977). This group forms an

important part of.the·�o·nd· macroinvertebrate community but

has been neglected or studied only superficially in many pond

studies.

INTRODUCTION TO CHIRONOMIDAE

13

The family Chironomidae is made up of ten subfamilies.

The distribution of each is determined by the availability of

suitable habitats for the larval stages (Oliver and Roussel

1983).

The subfamilies Aphroteniinae and Podonominae are found

most commonly in the southern hemisphere; Aphroteniinae is

completely restricted to this hemisphere. Both subfamilies

inhabit cold, swift flowing waters (Oliver and Roussel 1983).

The subfamilies Prodiamesinae and Oiamesinae are common

in high altitude and circumpolar cold lakes and rivers of the

world (Oliver and Roussel 1983).

Members of the subfamily Telmatogetoninae are marine

(Oliver and Roussel 1983). They inhabit the peripheral

regions of the temperate oceans. Some species also occur in,

swift running streams in Hawaii (Cranston 1983).

The subfamilies.Buchonomyiinae and Chilenomyiinae are

poorly known. Specimens of Buchonomyiinae are known from

rivers in Europe (Wilson and McGill 1982) and some have been

found in amber from Burma (Brundin and Saether 1978). The

subfamily Chilenomyiinae is known only from adults collected

near small brooks in Chile (Brundin 1983).

The remaining three subfamilies are the most common and

contain the majority of the species in the family (Oliver and

Roussel 1983).

The Tanypodinae and Chironominae are most abundant in

warm lentic and lotic habitats of the world. Their numbers

Edwards, and Baust 1983; Peckham 1971). Zealandochlus-------.---

14

decline in the colder waters (Oliver and Roussel 1983).

The subfamily Orthocladiinae is found in colder regions

of the world and decrease in abundance in warm areas.

Members inhabit both lentic and lotic habitats and many

semiaquatic habitats (Oliver and. Roussel 1983).

The family has radiated from the primitive habitat of

cold mountain streams (Brundin 1966) to almost every aquatic

habitat. Many species have adapted to specialized and

extreme habitats. For example; �el£i� �ntarctica Jacobs is

the largest indigenous organism found on Antarctica (Sugg,

l�lEalpis Brundin, a species of Podonominae, has been found

breeding in glacier meltwater at temperatures of 0.5 Celsius

(Oumbleton 1973). Many species are able to survive high

temperatures, greater than 50 Celsius, which occur in

Australian rock pools (Edward 1968).

A number of species have formed close relationships with

other organisms. Certain species of Cric�!£E�� live in

colonies of Nosto£ (Brock 1960; Wirth 1957). A few species

mine into aquatic macrophytes (Berg 1950) and decomposing

wood. Species of the genus ��tri��� live in pitcher

plants (Paterson and Cameron 1982). Many species form

phoretic or parasitic relationships with other aquatic

invertebrates including; ectoprocts, molluscs, and other

'aquatic insects (Oosdall and Mason 1981; Furnish et ale 1981;

Svensson 1980; White �1 �l. 1980; Mancini 1979; Forsyth and

15

McCallum 1978; Soldan 1978; Kurazhkovskaya 1971; Steffan

1965; Gillies 1951; Claassen 1922).

The family Chironomidae is a very important part of

aquatic �ystems, often being the most abundant and most

diverse insect group present. Densities of 50 000

individuals per square meter are common (Coffman 1984) and

densities of over 100 000 individuals have been reported

(Fagan and Enns 1966). In some systems, such as the

Saskatchewan River, they make up over 2/3 of the aquatic

insect species diversity (Mason 1983).

Most larvae are microphagous, feeding on algae and

detritus, forming an important basic link in the aquatic food

chain by converting algae �nd recy61ing detritus into the

food chain.

Many species are now being used as part of water

surveillance studies because they have specific tolerences to

various forms of pollutants (8eck 1977).

Chironomid adults sometimes form large mating swarms

which are annoying, often causing reduced usage of

recreational areas (Ali 1981, Johnsson and Mulla 1982,

Burrill 1913). In many areas of the world people suffer from

allergenic responses to these swarms (Cranston, �! ale 1981).

CHIRONOMIDAE LIFE HISTORY

Chironomidae are holometabolous insects. Their life

cycle consists of four life stages; egg, larva, pupa, and

adult.

16

Eggs are laid in a gelantinous matrix which expands to

several ·times its size upon contact with �ater. The shape

and number of eggs in the matrix are species dependent

(Olivet 1981)�

Hatching usually occurs within a few days after the eggs

are laid •. In some species the egg shell is ruptured by the

swelling of the prolarva (Danks 1971b). In Einfeldia-----

!lnchrona Oliver an "egg burster" is used to wear away an

initial hole in the egg shell then the larva swells by

ingesting water and ruptures the egg shell (Danks 1971b).

Eggs of Chironomus .2.2£.§.2.!is Meig. are laid in masses of

400 to 500 and half the eggs have hatched in about one and a

half days at 25 degrees Celsius (Sugimoto 1966). Eggs of

£infeldi� synchro� are laid.in masses of 500 and require

about three days to hatch at 10 degrees Celsius (Danks

1971b). About sixteen hundred eggs were found in each egg

mass of GIIPtot�.2iE� ��rb1E� (Staeg.); these r e qu I r ed

thirty hours to hatch at 32 degrees Celsius (Fagan and Enns

1966).

The larval stage is the longest stage of the life cycle

passing through four instars. The different instars can be

separated by the width of the head capsule (Reist and Fischer

1979; McCauley 1974).

The first larval ins tar or larvule spends a few days

within the gelatinous matrix before beginning a pelagic life

style (Danks 1971b). During this latter period the larvuie

17

is positively phototactic (Luferov 1971). It obtains

nourishment from the remaining yolk (Alekeyev 1965, cited in

Oliver 1981) and by feeding on suspended particles in the

water column (Danks 1971b; Oliver 1971). This pelagic period

is important in the dispersal of the larvae throughout the

water body (Davies 1973). When an appropriate habitat is

found the larvule becomes nega-tively phototactic and settles

into the life style of the later instars (Oliver 1971).

The life style of the remaining instars can be classed

into two basic types: sedentary and free-living. Many of

the Chironominae and Orthocladiinae build burrows on or in a

substrate and remain in these burrows until pupation (Oliver

and Roussel 1983). If the immediate microhabitat around the

burrow deteriorates these sedentary larvae are able to move

to more favourable microhabitats (Hynes 1961). Most

Tanypodinae and some species from other subfamilies are

free-living throughout the larval stage (Oliver and Roussel

1983).

The larval stage is the only feeding stage of the life

cycle. Food reserves accumulated by the larvae are used as

energy for the pupal and adult stages. Chironomid larvae

feed in four ways. The method employed depends on the

species, its life style and the microhabitat which it

inhabits (Walshe 1951).

The most primitive feeding methods used by later instars

is deposit feeding and scraping (Yoshimatsu 1967). This

18

method of feeding is used by both free living and burrowing

larvae (Walshe 1951). The main sources of food are detritus

and algae. There is still some argument as to whether these

larvae are selective feeders or not (Gerking, �! �1. 1975;

Davies 1975; and Alfred 1974).

A second feeding method used is filtering of suspended

particles from the water using nets made of salivary

secretions (Yoshimatsu 1967; Walshe 1951; Berg 1950; Leathers

1916). The larva builds a "Un shaped or straight burrow into

or on a substrate. It then spins a net across the diameter

of the burrow and undulates its abdomen causing a current of

water to pass through the burrow. Particles in the water

current are caught by the net. At regular intervals the net

and adhering particles are eaten by the larva and a new net

is spun to replace it (Walshe 1951).

, Species of the subfamily Tanypodinae and some species of

other subfamilies are either facultative or obligate

predators (Armitage 1968). Larvae in this group usually have

modified mouthparts 'for grasping prey. Smaller species and

early instars feed on algae and detritus as well as small

crustaceans and other chironomids. In larger larvae the

faunal component makes up a major part of the diet (Armitage

1968). Prey is consumed in two ways depending on its size.

If the prey is small it is engulfed whole by the larva, but

if it is larger the body contents are sucked out through a

break made in the body wall (Morgan 1949).

19

A number of species from many genera and subfamilies are

parasitic on other aquatic insects and molluscs (Steffan

1965).

Mature fourth instar larvae have swollen thoracic

segments which contain the developing cephalothorax of the

pupa. Pupation of burrow dwelling species usually occurs in

the last larval burrow. Pupae of free-living species are

also free-living. The pupal stage lasts for about two or

three days (Seattie 1978; Oliver 1981). When mature the pupa

swims to' the water surface where eclosion occurs.

Adults emerge from the pupal exuviae in a few seconds and

then flyaway. Adult emergences of a species from a single

habitat are usually synchronised with the season of the year,

time of day and environmental conditions (Oliver 1971).

Most species do not feed as adults, although some imbibe

sugary substances such as nectar and honeydew (Downes 1974).

The life span of these adults appears to be significantly

lengthened by feeding (Weissman and Edmein 1980).

Most chironomids form mating swarms to bring the sexes

together (Downes 1969). Swarms are formed over a marker

during a particular time of day. The type of marker, shape

of the swarm and time of·day the swarm.f6rms··is species

specific (Gibson and Lloyd 1945). Swarms are usually made up

of males of one species, mating pairs and fe�ales entering

the swarm (Gibson and Lloyd 1945). In some species, mating

is completed in midair, and lasts a few seconds. In other

20

species the mating pair falls to the ground and remains in

copula for several minutes. After mating the females fly to

an appropriate oviposition site. Egg maturation time is

poorly known but in most species the adult females emerge

f r om the pupae with well developed .f o Ll.Lc Le s (Oliver 1971).

Oviposition usually occurs over the water surface (Oliver

1981).

The length of the life cycle is determined by the

environment (Oliver 1971). In warm areas, species are

usually multivoltine and life cycles shorter than two weeks

have been reported (Syrja�aki 1965). Chironomids in

temperate regions have development interrupted by winter so

they are univoltin� or bivoltine (Oliver 1981). In these

regions of the world the larval stage is usually the

overwintering stage of the life cycle (Danks 1971a). In

severe climates, such as the high arctic, chironomids may

take seven years to complete their life cycle (Sutler 1982).

DIFFICULTIES STUDYING CHIRoNoMIDAE

Although the importance of the Chironomidae is usually

recognized, the family is usually dealt with at a superficial

taxonomic level in ecological and faunal studies. There are

many reasons for this neglect by chironomid nonspecialists,

but most are due to difficulties in classification and

species level identifications.

The family Chironomidae was first named in 1800 by Meigen

in a paper with very limited circulation. In it Meigen

21

referred to the family as Tendipedidae and two of the

subfamilies as Tendipenae and Pelopiinae with the respective

type genera as Te�di�� and E�£1� (Oliver and Roussel

1983). In 1803 Meigen published a second paper on the family

but referred to it as Chironomidae, the subfamilies as

Chironominae and Tanypodinae and the respective type genera

as Chl£g��� and TanYE�. The 1803 paper was widely

circulated and the names were in common usage (Oliver and

Roussel 1983). In the early 1900's, Meigen's 1800 paper was

"rediscovered" and a controversy developed over which

nomenclature was official. The problem was resolved in 1966

when the International Commission on Zoological Nomenclature

ruled to suppress the nomenclature of Meigen's 1800 paper in

favour of the nomenclature in his 1803 paper (Fittkau 1966).

A further classification problem is the concept of genus

within the family (Pinder 1983; Beck and Beck 1968). In most

of continental Europe, chironomid taxonomists were influenced

by a German school which emphasized the larval and pupal

stages when making taxonomic decisions. This resulted in

"narrow". generic limits (Beck and Beck 1968). In Britain and

North America, taxonomists generally placed emphasis on the

ad�lt �ale to decide taxonomic affinities (Pinder 1983).

This resulted in "wider" generic limits (Beck and Beck 1968).

Adult chironomids are usually more uniform than their

immature stages, because they are short lived, and only

disperse and reproduce (Fittkau 1962, cited in Oliver and

22

Roussel 1983). The immature stages, particularly the larvae,

have adapted to a wide range of microhabitats and are the

longest lived stage of the life cycle (Oliver and Roussel

1983). Adults which appear to have close taxonomic

affinities may have very diverse larval stages and the

opposite situation also occurs (Oliver and Roussel 1983).

The two systems produced massive synonomy problems

because larval specimens identified as one genus would often

belong to a different gen�s in the other taxonomic school.

In recent years the two schools of taxonomy have been slowly

amalgamated into one in which all life stages are considered.

As well as classification problems, there are a number of

practical problems which plague the study of this family.

Firstly, in most aquatic systems the larval density i� so

high that the numbers overwhelm the researcher. Secondly,

most species are small and appear superfically similar.

Identifying specimens, even to tribe, requires them to be

cleared, dissected and mounted onto microscope slides and

then examined using a compound microscope. Thirdly, because

the larval stage is the longest stage of the life cycle, it

is usually the most often collected. However most species

are described only from the adult stage. Often the immature

stages are not described, have not been collected, or can not

be distinguished from other species. To confirm

identifications using immature stages and to identify other

immatures to species, the immature stages must be reared to,

....

23

and associated with, adult males.

The above problems make chironomid species level taxonomy

very time consuming. In many studies, time and funding for

species level identifications is not available, so the family

is dealt with superficially as supraspecific taxa or

neglected all together.

POND CHIRONOMIDAE

Pond inhabiting Chironomidae have been poorly studied.

They are �sually studied as part of a regional survey such as

Roback (1976, 1957) and Gillespie (1974) for example, or, as

part of a pond ecological or faunal study such as Kenk

(1949), Judd (1964), Daborn (1974) and Wiggins et ale (1980).

Studies which deal specifically with pond chironomids are

few, but Rasmussen (1984, 1985), Driver (1977) and Danks

(1971b) are notable. Although pond chironomid studies are

few, they show that the family forms a major part of the

aquatic insect fauna of ponds (Rasmussen 1985; Daborn 1974;

Judd 1964).

Driver (1977) found that the chironomid fauna of a pond

was closely correlated to its permanence because of its

effect on the complexity of the plant community. The

chironomid diversity and the plant community complexity

'generally increases from temporary ponds, through

semipermanent ponds to permanent ponds (Driver 1977).

Driver found temporary ponds in the Floral area had 5.0

(+ or - 1.95 sd) species, and that the population was very

...

24

unstable, with a 50 to a 100 % turnover between years.

Generally temporary ponds were dominated by one or two

species; the most common species were from the subfamily

Orthocladiinae; �£!lcot£E� �itid��� (Mall.), bim�b��

cf. vunalis and Pesctr�cl�dius barbima� (Edwards) (Driver

1977).

The great changes in water levels of temporary ponds

result in simplified plant communities. This has an effect

on habitat subdivision, limiting the available microhabitats

and chironomid diversity (Driver 1977).

Chironomids have developed three strategies to live in

temporary ponds (Wiggins et �1. 1980). The first strategy is

to overwinter in the dry basin as larvae. Eggs are laid

during the short wet phase of the pond and development

continues until the basin dries out. To survive the dry

phase of the basin most of the species form cocoons made of

secretions. These cocoons are important in moisture

retention and protection from extremes in temperature

(Grodhaus 1980; Grodhaus 1976; Danks 1971c). Cocoon

formation is not restricted to temporary pond inhabitants as

larvae of many species in permanent habitats form cocoons for

protection from extfeme� in··temperature or low oxygen levels

(Danks 1971c). A further adaptation of many overwintering

species is a photoperiod regulated diapause in the fourth

instar larvae which prevents the larvae from pupating if the

basin is reflooded in the fall, and synchronizes the

25

emergence of adults in the spring (Wiggins �� �1. 1980).-

Chironomids which use this strategy include species of

Chi�!!!..!d.2' Endochir.2.!l2!!!..!d.2, Gli�otendi��, E�achironomus,

Earat..2.!2n���, _acricotopus, Crl.£ot.£E�' 's.!dkiefferiella,

��dro���, Psectrocladi�, Quttlpelo£ia and ££.2di�mesea

(Wiggins �! �1. 1980).

A second strategy of Chironomidae is to oviposit in the

dry basin. Species included in this group belong to the

genera Li�.£Ehx��, �£baenocladius and Smi�i!�, which

belong to the semiaquatic tribe, Metriocenemini of the

subfamily Orthocladiinae (Wiggins �� ale 1980).

The third strategy is to avoid the dry phase (Wiggins ��

al 1980). These include predatory and multivoltine species

in the genera .a.E1:abe�myia, E.!:ocl�di�, and Ps��!.2!..2.!2.l.E�.

Larvae overwinter in permanent habitats, adults emerge in the

spring, and mate, and .the females disperse to temporary ponds

where they oviposit. Larval development coincides with

abundant prey species. The immature stages develop rapidly

and the adults emerge before the pond dries. In ponds with

longer wet phases a number of generations may occur. These

species avoid food competition and predator pressures in the

permanent habitats by immigrating to the temporary ponds

where they exploit the rich food resources (Wiggins �! �1.

1980) •

Semipermanent ponds near Floral were characterized by a

larger number of species than temporary ponds, 19.9 (+ or -

26

6.26 sd) species (Driver 1977). These ponds were more stable

with a 25 % annual turnover rate in chironomid species

(Driver 1977). They may have one, two or several dominant

species. The most common species found in these ponds are

Ablabesmyia Eulchri�nnis (Lundbeck), fbl£2�� !���

Fab., lanytarsu� cf. lestagei and l��arsus sp. (Driver

1977).

During the wet phase of semipermanent ponds, water

fluctuations are not great enough to eliminate hydrophytes

which have complex morphologies (Driver 1977). These plants

subdivide the pond habitat more than plants with simpler

morphologies and provide a number of microhabitats suitable

for a more diverse chironomid community (Driver 1977).

Permanent ponds also have a more diverse chironomid

community than temporary ponds, 21.3 (+ or - 1.85 sd) species

(Driver 1977). The chironomid fauna is more typical of those

species which also inhabit lakes. The annual turn over rate

of species was the same as the semipermanent ponds, 25 %

(Driver 1977). However permanent ponds may change

dramatically in the chironomid fauna. Driver (1977) found

that during a three year period a permanent pond changed from

being a relatively homogeneo�s community with no species

dominating to a community where only two species dominated.

In permanent ponds low water fluctuations make the flora

and chironomid communities more stable. However this

stability also provides conditions suitable for a wider range

27

of organisms to live, increasing competition for. living space

and food. Of particular importance is the survival of

predators such as fish, which can affect the abundance and

diversity of pond inhabitants (Kenk 1949). Low water

fluctuations also reduce the amount of vegetation in the

basins which is exposed to aerobic decomposition. This

reduces the spring "pulse" of organic nutrients which occurs

in other pond types (Mackey 1979) and reduces the amount of

food available to the detritivores and filter feeders which

are fed upon by predators (Wiggins et ale 1980).

STUDY SITES

Pond A (SW-14-36-4-W2), the prima�y study site, is a

semipermanent fish free pond located 3.5 km North of Floral,

Saskatchewan. The pond basin (Fig. 1) covers an area of

about 1.8 hectares. It is bordered on the west by a gravel

road and on the other three sides by cultivated agricultural

land. Around the margin of the pond are isolated clumps of

Salix sp , and thick stands 'of Carex spp , and Sclorochia sp ,-- --- ----

This area was usually submerged during the early part of each

year and during flood conditions. Within this marginal area

is a five meter band of Typha �folia L. surrounding a

central open water area in which isolated clumps of 2�£2is

sp grow. The central area has an abundant growth of

submerged hydrophytes including �riophyllum spp.. The

substrate is a fine silty muck covered by a thick mat of the

28

water moss ��nocladi� sp •• As the water recedes the open

water area is slowly filled in with emergent vegetation

including £ol�� sp. and B��� sp. and mats of the alga

Cladophora sp •• On the water surface large populations of

Le� miD£! L. and b. trisulc� L. developed during the year.

Seven microhabitat types were distinguished in pond A:

central and peripheral benthos, Dre��Eladi� mat, submerged

vegetation, algal mats, emergent vegetation, and decaying

wood.

The basin of pond A was dry in the fall of 1981. In 1982

it contained about 20 cm of water at freeze-up. ' On June 24,

1983 the pond was filled to a depth of 120 cm due to a

torrential rainfall. At this time a small pond (pond F)

about 100 meters northeast of pond A flowed into the basin.

By freeze up there was still 70 cm of water in the basin. In

1984, after the initial spring peak of 100 cm, the pond

slowly lost water until September 10 when surface water had

completely disappeared from the basin. In late September

snow fall and rain refilled the basin to about 20 cm by the

time freeze up occurred.

To supplement the collections made from pond A,' other

ponds were sampled periodically during the study.

Pond B (SW-20-37-4-W3) is located 3.6 km north of

Kernan's prairie near Saskatoon. It is a large, shallow,

semipermanent pond covering an area of about to.O hectares.

During flood conditions it is part of a long network of

29

depressions, dugouts and intermittent creeks.

Pond C (NE-21-36-15-W2) is located 15.5 km Northeast of

Quill Lake, Sask •• It is a temporary pond with a maximum

area of about 0.8 hectares. The basin is almost entirely

covered by a stand of dead and decaying Sali� and is

surrounded by pastureland.

Pond D (NW-20-36-15-W2) is located about 1.6 km East of

pond C. The pond is semipermanent, covering an area of about

2.0 hectares. It drains cultivated cropland. In the fall of

1982 the pond basin was dry, at which time a small ditch.

about 2 meters deep was dug on the west side of the pond.

The ditch has extended the length of time the basin contains

water and may have made the pond permanent.

Pond E (SW-20-36-15-W2) is a temporary pond; pond F

(SW-14-36-4-W3) is of unknown permanence; pond G

(SE-15-36-4-W3), pond H (SE-13-36-4-W3), pond I·

(NW-9-36-4-W3) and pond J (SE-21-36-15-W2) are temporary

ponds and were all sampled once or twice during the course of

the study.

MATERIALS AND METHODS

SAMPLE COLLECTION

Pond A was visited a few times during late summer in 1982

and at approximately weekly intervals from April to September

or October in 1983 and 1984. Other ponds were visited once,

or at most a few times during the course of the study •

....

30

Qualitative samples of the benthos, submerged vegetation,

algal mats and open water were taken using a D-shaped aquatic

dip net with a mesh size of 1 mm; and two sieves with a mesh

size of 2.5 mm. Samples were washed free of silt and preser

ved in 95 % alcohol for sorting under a stereoscopic

microscope in the laboratory.

Representative fourth instar larvae, distinguished by the

swollen thoracic segments, and pupae, used for rearing were

transported to the laboratory in pond water.

The water surface was sampled for emerging chironomids

and pupal exuviae by sweeping with a small sieve. The

specimens collected were used for taxonomic study and to

qualitatively determine the approximate emergence times of

the more common species.

An aerial sweep net was used to'collect adult chironomids

from.the emergent vegetation that surrounded the pond.

Submerged decaying �li� sp. branches were examined for

associated chironomid larvae.

ENVIRONMENTAL INFORMATION

Each time a pond was visited the date and time were

recorded, and air and water temperatures (at 35 cm below the

water surface if possible) were measured (Table 1). A number

of environmental parameters were also noted: cloud cover

(clear, scattered cloud, partly cloudy, overcast); wind

direction and speed (calm, light, moderate, strong).

Observations on pond conditions were also recorded;

31

chironomid emergences, extent of emergent vegetation growth,

presence of algal blooms, and any abundant fauna.

Photographs were taken on various dates to document the

pond's development throughout the year.

REARING

In the laboratory, individuals used for rearing were

placed in four dram vials with about six ml of dechlorinated

tap water. The vials were stoppered with cork or cotton

plugs and placed in an incubator with a 16 hr/8 hr light/dark

photoperidd. The temperature was kept at the current

temperature of the pond to a maximum of 20 degrees Celsius -

above this temperature bacterial and fungal growth greatly

reduced rearing success. When an adult emerged it was

transferred to a dry vial and left for about a day to allow

the cuticle to harden. The adult was then preserved in 70 %

ethanol with its larval and pupal exuviae.

SLIDE PREPARATION

Representative reared adults, larvae, pupae and pupal

exuviae were dissected and mounted on microscope slides for

taxonomic identification. The two procedures used in this

study were adapted from Mason (1983), Oliver and Roussel

(1983), and Simpson and Bode (1980).

Larvae and pupae were cleared in two ways. (1); By

passing the specimens through the following series of baths:

cold 10 % KOH for eight to 24 hours (depending on specimen

size); distilled water for ten minutes; 2-proponal for 15

.....

32

minutes; and 2-proponal layered over cedarwood oil for 15

minutes and then mounted on the microscope slide in Canada

Balsam. Or (2), by placing the specimens in a bath of warm

(50 degrees Celsius) 10 % KOH for ten to twenty minutes (for

large larvae the abdomen was punctured a number of times

along its length with a pin; large pupae were dissected

before being placed in the 10 % KOH), next, a distilled water

rinse for five minutes, and then 95 % ethanol for ten

minutes. Specimens were then mounted on a microscope slide

in Euparal.

Pupal and larval exuviae were mounted directly into

Euparal.

After a larva was cleared it was placed on a microscope

slide in mounting medium and decapitated. The width of the

head capsule was measured using an ocular micrometer at 100

x, and the presence or absence of tubules on the tenth and

eleventh body segments was noted. The head capsule was

placed under a coverslip ventral side up and then squashed to

spread the mouth parts. The abdomen was placed laterally

under another coverslip on the same microscope slide. Larval

exuviae were not dissected. They were positioned with the

head capsules ventral side up and then squashed under a

coverslip.

The cephalothorax and abdomen of pupae were dissected

apart before clearing. After clearing the cephalothorax was

placed laterally in a drop of mounting medium on a microscope

.....

33

slide and the abdomen was positioned dorsal side up. The

slide was then placed in an oven at 45 degrees Celsius for 24

hours to harden the mounting medium before more medium and

the coverslips were put on. This was done to reduce

distortion of certain taxonomically important features by the

weight of the coverslip •.

Pupal exuviae were dissected in the same manner as pupae,

but the cephalothorax was split down the ecdysial suture,

then turned over and spread out so the ventral side was up.

The abdomen was postioned dorsal side up on the microscope

slide. These specimens were also allowed to bake for 24

hours before coverslips were placed over them to reduce

distortion.

Adult specimens were dissected as follows: the head,

thorax and abdomen were dissected apart; the left legs and

the wings were pulled off (the left wing complete, the right

wing with the squama left attached to the thorax); and the

antennae were pulled off the head. The head, thorax and

abdomen were cleared using cold KOH; the left legs, wings and

antennae were cleared by placing them in 2-proponal layered

over cedarwood oil. The cleared parts were then mounted in

Cana6a ��lsam or Euparal. If Euparal was used the 2-proponal

layered over cedarwood oil bath was deleted.

The adult parts were positioned on the same microscope

slide as follows: the head anterior side up; the thorax

right side up; and the abdomen dorsal side up. Coverslips

....

34

were placed over the specimens after they were baked for 24.

hours to reduce distortion.

For reared material, each of the life stages was placed

on the same microscope slide as shown in Fig. 2.

The completed slides were baked in an oven at 45 degrees

Celsius for three weeks for slides made with Euparal and six

weeks for slides made with Canada Balsam. After this time

the microscope slides were ready for examination.

ILLUSTRATION METHODS

Line drawings were made using an American Optical

compound microscope equipped with a drawing tube.

Photomicrographs were taken using a Ziess photographic

microscope.

VERIFICATION AND DISPOSITION OF SPECIMENS

Identifications of specimens were verified by Mr. B.

Bilyj of the Freshwater Institute in Winnipeg and by M. E.

Dillion and Dr. D. R. Oliver of the Biosystematics Research

Institute, Ottawa.

Specimens will be placed in the collections of the

author, Dr. D. M. Lehemkuhl, B. Bilyj and the Canadian

National Collection.

35

INTRODUCTION TO BIOSYSTEMATIC SECTION

Chironomid systematics have greatly improved in recent

years due to the concentrated efforts of a number of

researchers around the world; Brundin, the Beck's, Cranston,

Fittkau, Oliver, Roback, Saether, and the Sublette's to name

a few. Two of the major achievements of these researchers

has been the slow. amalgamation of the two schools of taxonomy

into one in which all life stages are considered in making

taxonomic decisions. The other achievement has been the

initiation of a three volume work on the Holarctic

Chironomidae including keys, diagnoses, ecological notes and

distributions. In 1983 the first volume, dealing with the

larvae, was published as a series of supplements of the

journal Entomologica Scandinavica. The other two volumes

covering the pupae and adults will be in print soon.

In Canada Oliver and Roussel (1983) have written a work

on chironomid larvae of Canada which has greatly improved the

understanding of larval Chironomidae at the genus level in

this country.

In Saskatchewan most work on chironomids has been

superficial, usually as part of an ecological study.

Examples are Hamilton (1961), Gregory and Loch (1973),

MacMillan (1971), Mendis (1956), Tones (1970) and Warwick

(1979, 1967). Exceptions are work done by Rempel (1936,

1937) describing individual species, Swanson's (1978) study

of f!icotoE� �at�� in Waldsea Lake, Driver's (1977) work

.....

36

on pond chironomids as indicators of pond permanence, and

Mason's (1978, 1983) studies on the Chironomidae of the

Saskatchewan River system and Tobin Lake. As noted above

Saskatchewan pond chironomids have been studied only by

Driver (1977).

FAMILY TERMINOLOGY

The family, subfamily and generic diagnoses appearing in

this work have been compiled from a number of sources, the

most important being; Cranston �! a1. (1983), F i ttkau and

Roback (1983), Mason (1983), Oliver and Roussel (1983),

Pinder and Reiss (1983), Wilson and McGill (1982), Mason

(1978) and Gillespie (1974).

The terminology of the taxonomic characters follows

Saether (1980).

LARVA: The larva is divided into three parts (Fig. 3): a

�ell defined, sclerotized head capsule and twelve body

segments, three thoracic segments and nine abdominal

segments. The head capsule has most of the important

features on it.

Head capsule: (Fig. 4 and 5).

Antenna: Length ranges from longer than head capsule to

shorter than mandibles •... They··are made up of four to eight

segments. In the subfamily Tanypodinae the antennae are

retractile into the head capsule (Fig. 4). In the tribe

Tanytarsini the antennae are situated on antennal tubercles

(Fig. 122). A ring organ (Fig. 62) and sensory hairs (Fig.

37

149) are found in some species. On the apex of the first

segment is an antennal blade. A pair of Lauterborn's organs

are usually present on the apex of the second antennal

segment; sometimes they are located on long petioles (Fig.

136) in the Tanytarsini.

Labrum: Usually has a number of seta anteriores, SI and SII

(Fig. 5) being the most important. In.some species a

vari�bly developed pecten epipharyngis (Fig. 56) are present.

The Chironominae and Orthocladiinae have a pair of apically

toothed, premandibles (Fig. 5)'which may have premandibular

brushes on them (Fig. 130).

Mentum: In the Chironominae and Orthocladiinae it is a

sclerotized anteriorly toothed plate (Fig. 5) with an

associated ventromentum.

Prementohypopharyngeal complex: In the Tanypodinae it is

well developed. It is made up of a variably toothed ligula,

pecten hypoharyngis and paraligula (Fig. 4). Associated with

these structures are a variably developed dorsomentum.

Anterior to this is a lobed M-appendage, 'often with a

pseudoradula running down its length.

Maxillary palp: Usually one segmented.

Mandible: With an apical tooth of varying length and color.

Some species have a single dorsal tooth or a series of teeth

on the dorsal surface (Fig. 19). The inner margin may have a

series of inner teeth (Fig. 40). Below the last inner tooth

is a variably developed seta subdentalis. Also present in

...

38

some species are two groups of seta referred to as the pecten

mandibularis and seta interna.

Body segments: (Fig. 3).

The thorax and abdomen do not differ in shape until late

in the fourth instar when the thoracic segments become

swollen •. The first segment usually has a pair of anterior

parapods each with an apical crown of claws. Body segments

II to VI often have variably developed setae, sometimes

forming a setal fringe. In the Chironominae body segment IX

may have a pair of lateral tubules on the posterior corners,

and body segment X may have one or two ventral tubules. The

dorsal surface of body segment XI usually has a pair of

procerci each with anal setae and sometimes a spur (Fig.

178). Body segment XII usually has two separate apically

clawed posterior parapods and one or two pairs of anal

tubules�

PUPA: The body of the pupa is divided into two parts; the

anterior cephalothorax and the �bdomen.

Cephalothorax: (Fig. 6).

On the anterior surface there are usually a pair of

cephalic tubercles which may have a frontal seta on each

(Fig. 51). The dorsal surface may be nodulated or smooth.

On the dorsal-lateral surface are.usually a pair of thoracic

horns which may be trumpet shaped with a plate on the apex

(Fig. 13), plumose (Fig. 6), tubular (Fig. 133), club shaped

and covered with spines (Fig. 160) or absent.

......

39

Abdomen: (Fig. 7).

The abdomen is made up of nine segments. The tergites

usually have a variably developed armature of small spinules,

spines and/or maces like processes. T�rgite II usually has a

variably developed row of hooks on the posterior margin of

the tergum. Pedes spurii B, small humps on the lateral edges

of segment II, are often present (Fig. 190). Most segments

have a varying number of lateral setae. A spur or comb is

usually present on the caudolateral corners of segment VIII.

The abdomen ends in a pair of variably formed anal lobes

which may be bare, with a hair fringe and/or �acrosetae (Fig.

24, 71, 147, 180)�

MEASUREMENTS AND RATIOS:

All measurements refer to maximum lengths of the

structures and are explained in the text.

One ratio, the antennal ratio (A. R.), is an important

taxonomic character. It is the length of the basal antennal

segment divided by the total length of the terminal antennal

segments.

40

KEY TO CHIRONOMIDAE SUBFAMILIES

collected in study

LARVAE

1a. Antennae retractile into head capsule ••• Tanypodinae

1b. Antennae nonretractile •••••••••••••••••••••••••••• 2

2a. Ventromental plates well developed, with striations •

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Chironominae

2b. Ventromental plates poorly developed, never with

striations, sometimes with a beard ••• Orthocladiinae

PUPAE

1a. Thoracic horns plumose, branched wide-Iumened tubes

or a single lang tube. Anal lobes never with macro­

setae but with a hair fringe ••••••••••• Chironominae

1b. Thoracic horns club-shaped, tubular or absent, often

covered with spines or reticulations. Anal lobes with

macrosetae and/or hair fringe present or absent •••• 2

2a. Anal lobes usually large, never with terminal macro­

setae. Scar present an abdominal tergite one.

Thoracic horns large often with a large plate

structure on'terminal end •••••••••••••••• Tanypodinae

2b. Anal lobes smaller bare or with a hair fringe and/or

terminal macrosetae. Thoracic horns without plate an

terminal end ••••••••••••••••••••••••••• Orthocladiinae

-

41

TANYPODINAE

LARVA: Small to large in size. Color creamy white and

yellow to red or green.

Antennae: Usually four segmented, rarely five segmented.

Second segment always longer than third. Capable of

retracting into the head capsule. Antennal ratios vary from

2.5 to 16. Ring organ usually present. Lauterborn's organs

usually indistinct. Antennal blade and accessory blade about

as long as terminal segments.

Labrum: Weakly sclerotized, with a series of seven pairs of

ventrally oriented sensory hairs and pegs. Premandibles

absent.

Prementohypopharyngeal complex: Ligula usually with five

dark teeth, anterior margin concave, straight or slightly

convex. Paraligula usually bifid. Dorsomentum present, as

low toothed plates or a sclerotized complex with anteriorly

directed teeth. M-appendage triangular with vesicular lobes

laterally and a pseudoradula. Pecten hypopharyngis usually

with ten to twenty teeth.

Mandibles: With a long acute apical tooth and usually a

basal tooth, with seta subdentalis inserted in it, and an

inner ventral accessory tooth. Rarely with a series of inner

teeth.

Maxillary palps: Well developed, one to six segments, basal

segment with a ring organ.

Body: With paired apically clawed anterior and posterior

42

parapods. Body segments may have a well developed lateral

fringe of swim setae. Procerci well developed.

PUPA: Medium sized, 2 to 11 mm long. Color creamy yellow to

light brown.

Cephalothorax: Thoracic horns variably developed, with open

spiracles and plastron (sieve) plates present or absent •. In

some species a toothed comb, the thoraxkamm, is present at

the base of the thoracic horn.

Abdomen: A scar on tergite I may be present. Abdominal

tergites usually with sparse" uniform shagreen. A variable

number of lateral setae present on the abdominal segments.

Anal lobes may be short and rounded, or almost triangular;

with a hair fringe and/or two pairs of macrosetae.

KEY TO TANYPODINAE GENERA

collected in study

LARVAE

1a. Ligula with 5 teeth •••••••••••••••••••••••••••••• 2

1b. Ligula with 4 teeth� ••••••••••••••••••••••••••••• 4

2a. Maxillary palp with two segments (Fig. 11) ••••••••

••• ••••••••••••••••• ••••••••••••••••• •• Ablabesmvia---�-

2b. Maxillary palp with one segment •••••••••••••••••• 3

3a. Teeth of ligula concave (Fig. 32) ••••••• Procladius

3b. Teeth of ligula convex (Fig. 45) ••••••••••• lanypus

4a. Dorsomentum distinctly concave (Fig. 18). Most

lateral two teeth fused •••••••••••••••• Derota���

-

-

43

4b. Dorsomentum straight or slightly concave.

(Fig. 39) Most lateral two teeth not fused ••••••••

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Psectro�n�pus

PUPAE

1a. Thoracic horn sac-like, with a small plastron

plate (Fig. 13) •••••• � ••••••••••••••••••••••••••• 2

1b. Thoracic horn trumpet shaped, with a relatively

large platron plate (Fig. 22) •••••••••••••••••••• 3

2a. Anal lobes small and rounded, shorter than VIII

segmen ••

'

••••••••••••••••••••••••••••••••••• Tanypus

2b. Anal lobes medium sized, triangular and pointed

( Fig. 12, 15) •••••••••••••••••••••••••• ll�be�tl.§!

3a. Anal lobes biconvex, margins fringed with hairs

internally and externally (Fig. 24) •••••••••••••• 4

3b. Anal lobes with inner side straight and the outer

side rounded (Fig. 30, 37) •••••••••••••• Procladius

4a. Thoracic horns narrow L/W ratio 3.34 to 4.45.

Respiratory atrium fills horn (Fig. 41) •••••••••••

. . . . � . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £� c t rot a nX.P.!:!�

4b. Thoracic horns wider L/W ratio 2.9 or less.

Respiratory atrium slightly narrowed at junction

of plastron plate. Internal supporting .s t-r uc t ur e s

visible (Fig. 22) •••••••••••••••••••••• Derota!!.l.E.!:!.§.

Ablabesmyia Johannsen

Johannsen 1905. Bull N. Y. State Mus. 86:135

44

Larva: Medium to large, up to 11 mm. Head capsule longer

than wide. Antennae four segmented. Antennal ratio greater

than 4. Ligula with five teeth, anterior margin concave.

Paraligula bifid. M-appendage a vesicular structure with a

pseudoradula. Dorsomentum reduced, teeth absent. Maxillary

palp's basal segment divided into two to six segments.

Anterior parapods separate, each crowned with small claws.

Abdominal segments without setal fringe. Procerci twice as

long as wide, each with 7 anal setae.

Pupa: Thoracic horns large and ovate, with a small plastron

plate. Thoraxkamm present at base of thoracic horns. A scar

present on tergite I. Anal lobes almost triangular, with one

pair of setae in anteiior portion, inner margins smooth.

REMARKS: The genus Abla�m�i� has more species than any

other in the subfamily Tanypodinae (Fittkau and Roback 1983).

It has been divided into three subgenera; �bl�esmyia (s.

str.) and�. (��ia) and�. (2artaia) (Roback 1983, 1971).

The immatures of most species are not well known and cannot

be separated into species without associated adult material

(Fittkau and Roback 1983).

Larvae inhabit warm lentic waters and the slower areas of

lotic habitats (Oliver and Roussel 1983). Some species are

tolerant of low oxygen levels and·pollution (Wilson and

McGill 1982, Beck 1977).

�blabesm�ia is a Holarctic genus. Thirteen species have

been identified from the Nearctic and four from the

45

Palearctic (Fittkau and Roback 1983). In North America the

genus is widespread south of the treeline (Oliver and Rousell

1983).

In this study one species was collected.

Ablabes��ia (�arelia) pulchripenni� (Lundbeck)

(Figures 8 to 15)

Lundbeck. 1898. Vide Med. Nat. For. Kjobehavn: 293

LARVA: n = 10

Antenna: Length of first segment 638 (560-740) urn; antennal

ratio 6.3 (5.6-6.7). Ring organ 0.50 (0.47-0.56) from the

base of the first segment. Blade as long as terminal

segments.

Prementohypopharyngeal complex: Ligula with five dark teeth,

most lateral teeth splayed outward; length 130.0

(120.0-137.5) urn. Paraligula short, unequally bifid, inner

tooth one third length of outer tooth. Pecten hypopharyngis

with 19 (15-23) teeth.

Mandible: Length 233.5 (212.5-260.0) urn; with an accessory

tooth and inner tooth present. Apical tooth dark.

Maxillary palp: Two segmented; first segment 49.5

(40.0-60.0) urn long, second segment 59.0 (50.0-66.3) urn long.

B6dy: :Pos�erior parapods separate, each with a crown of

claws. Two claws darker than the others, one dark claw

larger than the other.

PUPA: n = 10, unless otherwise stated.

Color: Yellowish brown •

.....

.....

46

Length: Total length 7.5 (6.9-8.3) mm; abdomen 5.7 (5.3-6.5)

(n=9) mm.

Cephalothorax: Thoracic horn length 693.6 (580.0-840.0)

(n=7) urn, width 322.0 (280.0-390.0) um; plastron plate

reduced to a small apical protuberence; surface reticulate

with spines. Thoraxkamm a well developed comb of teeth.

Abdomen: Tergites I to VIII with fine uniform shagreen.

Tergite I with an elongated scar 273.2 (260.0-330.0) um long.

Segments VII and VIII with 4 and 5 lateral setae

respectively. Anal lobes two times longer than genital sacs;

outer margins with two medial macrosetae; apex with small

teeth on outer margin.

BIOLOGICAL NOTES: Ablabesmyia pulchrip�nis was commonly

collected in pond A from submerged macrophytes and algae.

Larval guts contained detritus, small crustaceans and

chironomid larvae. In 1983 pupal exuviae were collected from

pond A most often during June and early July.

REMARKS: The adult specimens key to �. �Eh!l�nnis in

Roback (1971). The immatures have not been previously

described.

DISTRIBUTION: �. pulchripennis has been collected from

Greenland; AB, SK, MB, PO in Canada and from WA, CO, SO, MT

and FL in the United States (Driver 1977; Roback 1971; Beck

and Beck 1966; Sublette and Sublette 1965).

MATERIAL EXAMINED: Pond A: 4 reared males, 5 males with

associated pupa, 2 pupa with associated larva, 1 pupa, 37

47

pupal exuviae, 52 larvae.

Derot�� Roback

Roback 1971 Mon. Acad. nat. Sci. Philad. 17:91

LARVA: Large, up to 13 mm. Antenna four segmented, antenna 1

ratio 5.9 to 9.0. Ligula with four teeth, anterior margin

straight. Paraligula pectinate. Dorsomentum distinctly

concave on each side. Maxillary palps with a single basal

segment. Abdominal segments with a setal fringe. Smallest

claws of posterior parapods highly arched or simple.

PUPA: Thoracic horns with supporting rings and rods visible.

Thoraxkamm absent. Scar on tergite I semiquadrate. Lateral

setae on VII and VIII, 6 and 5 respectively. Anal lobes

biconvex, slightly asymetrical; hair fringe on both' inner and

outer margins, two macrosetae present on anterior half of

each lobe.

REMARKS: The status of �.!ot�1.E� as a genus appears to be

in question. Roback (1971) elevated it to full generic

status based on adult characters, but in a later paper

(Roback 1978) he reduced it to a subgenus of Ps�rotanypus

based on immature characters. DerotaDX� was again raised

to generic status in Fittkau and Roback (1983) and Oliver and

Roussel (1983). The immature stages of all species are

poorly known (Fittkau and Roback 1983).

The larvae inhabit small ponds and slower areas of lotic

conditions (Oliver·and Roussel 1983). Some species are able

48

to tolerate high salinities (Oliver and Roussel 1983).

�otanypus is Holarctic in distribution. In the

Palearctic three or four species are known from Europe,

China, and the northern Alps (Fittkau and Roback 1983).

Three species are known from the Nearctic (Fittkau and Roback

1983).

One species was collected in this study.

Derota��� alaskensis (Malloch)

(Figures 16 to 24)

Malloch. 1919. Can. Arctic. Exped. 3:35C

LARVA: n = 10, unless otherwise stated.

Antenna: First segment 302.6 (281.0-330.3) urn long; antennal

ratio 7.3 (6.2-9.7); ring organ position 258.4 (242.0-283.5)

(n=7) urn from base of first segment. Antennal blade subequal

or slightly shorter than terminal segments.

Prementohypopharyngeal complex: Ligula 133.2 (108.8-164.5)

urn long; with four light brown to pale yellow teeth.

Anterior margin of ligula, outer teeth slightly splayed

outwards. Paraligula with ten or more branches, often

subsequently branched, almost the same length as ligula.

Pecten hypopharyngis with 25 or more teeth. M-appendage as a

rounded dome with lateral. 16bes� . Dorsomentum with five or

six teeth, the outer two teeth partially fused and directed

anteriorly.

Mandible: Length 263.6 (240.4-288.4) urn; with three or more

inner teeth and a patch of small teeth on the dorsal surface

49

of the mandible. Apical tooth dark.

Maxillary palp: Basal segment; 64.0 (54.4-73.5) um long.

Ring organ 42.5 (36.7-50.6) um from base of segment.

Body: Procerci about 3.5 times as long as wide, with 20 anal

setae or more. Posterior parapods long, crowned with light

colored claws, the smallest claws highly arched.

PUPA: n = 10, unless otherwise stated.

Color: Light brown, each abdominal segment with a posterior

median region dark brown.

Length: Total length 9.5 (8.1-10.5) (n=8), abdominal length

7.5 (6.3-8.6) (n=9) mm.

Cephalothorax: Thoracic horns dark brown 676.9 (645.0-720.0)

(n=8) um long, and 283.8 (246.5-330.0) (n=7) um wide. The

surface is covered by fine spines. Respiratory atrium is

slightly narrowed just below plastron plate.

Abdomen: All tergites with uniform minute spinules. Lateral

setae VII-6, VIII-5. Anal lobes about twice as long as wide,

biconvex, apical point medial, two large lateral setae in

anterior of each anal lobe.

BIOLOGICAL NOTES: Pupae and late larval instars were

collected from shallow benthos, algal mats, and

Dr��cladius sp. mats in pond A. The digestive tracts of

the larvae contained, detritus, diatoms, ostracods and

chironomid larvae and pupae.

REMARKS: The adult male specimens examined are slightly

smaller than those described by Roback (1971).

50

DISTRIBUTION: Q. ���nsis has been collected from Alberta,

Saskatchewan, Manitoba and the Yukon and Northwest

Territories, and from Ala�ka (Roback 1971).

MATERIAL EXAMINED: Pond A: 3 reared males, male associated

with pupa, 2 reared females, 4 pupae, 4 pupae associated with

larvae, 2 pupal exuviae, 9 larvae. Pond B: 2 larvae. Pond

D: 2 larvae.

Erocladius Skuse

Skuse 1889. Proc. Linn. Soc. N.S.W. 2:283

LARVA: Medium sized, 6 to 11 mm long. Antennae four

segmented, about as long as mandibles. Dorsomentum with six

to eight teeth. M-appendage with distinct pseudoradula.

Ligula with five teeth, anterior margin concave. Paraligula

with a long apical branch and a variable number of inner and

outer branches. Pecten hypopharyngis with 10 to 15 large

teeth. Mandibles with one inner and one accessory tooth.

Anterior parapods separate with an apical crown of claws.

Body with fringe of swim setae. Procerci two to four times

longer than wide.

PUPA: Exuviae hyaline or slightly pigmented. Thoracic horns

vase shaped, with obvious plastron plates. Respiratory

atrium narrow and tapering, or medially expanded. Anal lobes

large, with fine sawlike teeth on outer margin, inner margin

bare. Apices of anal lobes rounded or pointed, two

macrosetae present on anterior half of each lobe.

51

REMARKS: E£££ladius has been divided into three subgenera;

_e roc 1 ad i u� (s. s t r • ), 1:. ( HoI 0 t�� ) and _e. ( Psi 1.Q.E tan y�� )

(Fittkau and Roback 1983).

Larvae inhabit all types of freshwater (Oliver and

Roussel 1983). Most species prefer the muddy sediments of

lentic waters and slow flowing areas of lotic environments

(Fittkau and Roback 1983). The larvae are tolerant to low

oxygen levels (Wilson and McGill 1982).

Procladi� has a world wide distribution. Eighteen

species of E. (�lotanypus) and three species of _e.

(PsiloBtanxpus) are known from the Nearctic (Roback 1971).

_erocladius (s. str.) is not found in the Nearctic (Fittkau

and Roback 1983).

Two species were collected in this study.

KEY TO SPECIES

LARVA:

1a. Anterior margin of ligula very concave (Fig. 32).

Pecten hypopharyngis with 15 or more teeth •••••••••

•••••••••••••••••••••••£rocladius (�olot���) sp.

1b. Anterior margin of ligula slightly concave

(Fig. 26). Pecten hypopharyngis with five or

fewer teeth ••••••• Procladiu§ (Psiloptan�) nietu�

PUPA:

1a. Abdomen clear to dark. Inner corners of anal lobes

produced to a slight point (Fig 37) ••••••••••••••••

•••••••••••••••••••£rocladiu§ (Holotanxpus) sp.

-

52

1b. Abdomen clear. Inner corners of anal lobes rounded

(Fig. 30) ••••••••••£!£cladius (Esilotan�) niet��

Procladius (Psilotan�) nietus Roback

(Figures 25 to 30)

Roback. 1971. Mono. Acad. Nat. Sci. Phiadelphia 17:168

LARVA: n = 1

Antenna: First segment 142.0 um, antennal ratio 4.54. Ring

organ 120.0 um from base of first antennal segment. Antennal

blade length 28.0 um.

,Prementohypopharyngeal complex: Ligula with apical'half

black, length 75.0 um, width 48.0 um. Paraligula 37.5 um

long, four outer lateral teeth no inner teeth. Pecten

hypopharyngis greatly reduced, five teeth present.

M-appendage broken and obsc�red. Dorsomentum with seven

lateral teeth present on each side, slightly concave.

Mandible: Length 130.0 um. ,Apical tooth dark near apex.

Maxillary palp: Single basal segment 29.0 um long.

Body: Procerci 2.5 times longer than wide with 14 anal

setae. Smallest claws of posterior parapods short and

slightly ovoid in shape, none have toothed inner margins.

PUPAE: n = 1

Color:

Length:

Cephalothorax light brown, abdomen pale.

Total length 6.03 mm, abdominal length 4.32 mm.

Cephalothorax: Thoracic horn 270.0 um long, L/W ratio 1.8.

Respiratory atrium narrower than thoracic horn, narrows

......

53

distinctly just below plastron plate.

Abdomen: Without lateral hair fringe. Tergite I with long

narrow scar, length 231.7 um, width 24.7 um. Shagreen on

tergites uniform, of small, sparse spinules. Lateral setae

on VII-4, VIII-5. Anal lobes 690.0 um long, mediocaudal

corners rounded, inner margins straight, external margins

rounded, two anterior macrosetae. About 56 saw like teeth on

caudal and external margins of lobes.

BIOLOGICAL NOTES� The specimen collected emerged in May.

REMARKS: The adult male keyed in Roback (1971).

DISTRIBUTION: £. ni�� has previously been recorded from

British Columbia and Manitoba (Roback 1971).

MATERIAL EXAMINED: Pond A: reared male.

E!£cladius (Holotanypus) sp.

(Figures 31 to 37)

Roback. 1971. Mono. Aca. Nat. Sci. Philadelphia. 17:188

LARVA: n = 1

Antenna: First segment 198.0 um long, antennal ratio 5.27.

Ring organ 150.0 um from base of first segment. Antennal

blade 32.5 um long.

Prementohypopharyngeal complex: Middle tooth of ligula much

smailer than lateral teeth; toothed area dark. Ligula 127.0

um long, 86.0 um wide. Paraligula with one inner tooth and

three teeth on lateral side of main branch, length 50.0 um.

Pecten hypopharyngis with 15 or more teeth. M-appendage, a

large vesicular structure with two lateral lobes;

54

pseudoradula distinct. Each side of the dorsomentum is

slightly concave, with seven teeth.

Mandible: Mandibles 190.0 um long. Apical tooth brown and

acute.

Body: Procerci three times as long as wide, bearing more

than 25 anal setae. Smallest claws of posterior parapods

highly arched.

PUPAE: n = 1

Color: Exuvium pale; thoracic horns brown.

Length: Total length 7.1 mm, abdominal length 5.3 mm.

Cephalothorax: Thoracic horn 550 um long, L/W ratio 3.38,

dark with fine retculations. Respiratory atrium distinctly

narrower than thoracic horn, becoming narrower just below

plastron plate.

Abdomen: Without lateral hair fringe. 'Shagreen on all

tergites.uniform and sparse. Scar on tergite I obscured.

Lateral setae VII-4, VIII-5. Anal lobes 920 um long, with

about 60 sawlike teeth on outer edge; inner margin straight,

mediocaudal corner slightly produced; outer margin rounded;

two large setae on anterior half of lobes.

BIOLOGICAL NOTES: The larva was collected from the central

benthos of Pond A.

REMARKS: The specimen keys to Prolcadius (Holotanypus) in

Fittkau and Roback (1983). The larvae key to � (�.) pOSSe

prolo�� in Roback (1980). The pupal exuvium also keys to

E. E!olongatus with slight descrepanices which may be due to

.....

-

55

geographical variation. The adult male is needed for

positive species identification.

MATERIAL EXAMINED: Pond A: reared female.

Psect�nypus Kieffer

Kieffer. 1909. Bull. Soc. His. Nat. Metz. 26:42

LARVA: Large, up to 11 mm. Color greenish, yellow or

reddish. Antennae four segmented, antennal ratio greater

than 6. Ligula with four teeth, anterior margin concave;

paraligula pe�tinate. Dorsomentum straight or slightly

concave with six to eight teeth. Mandibles with four to

eight saw-like inner teeth. Anterior parapods separate, each

with a crown of claws. Abdominal segments with a setal

fringe. Procerci three or more times longer than wide.

Small claws of posterior parapods simple or with an oval

base.

PUPA: Medium sized, chestnut brown. Thoracic horns almost

parallel sided. Scar on tergite I circular to quadrate.

Anal. lobes symetrically biconvex, inner and outer margins

fringed with large tooth like hairs.

REMARKS: Psectrotanypus has been divided in into two

subgenera on two ocassions; �ctrota!!1�' .(.s.· .. st r , ); and E.

(�tanypus) based on adult characters (Roback 1971;) and £.

(s. str.) and E. (,t!psectrotanypus) based on. immature

characters (Roback 1978). Recently �rotan� and

,t!psectr£!anypus have been raised to full generic status

56

(Fittkau and Roback 1983).

The larvae prefer small, warm, eutrophic, lentic waters

and the slower areas of rivers (Fittkau and Roback 1983;

Oliver and Roussel 1983). Larvae of some species can

tolerate polluted conditions (Wilson and McGill 1982).

Three species are known from the Nearctic and one from

the Palearctic (Fittkau and Roback 1983). In North America

the genus is distributed from Alaska to Newfoundland and into

the southern United States (Oliver and Roussel 1983; Roback

1978).

One species was collected in this study.

Psectrotanypus dxari (Coquillet)

(Figures 38 to 43)

Coquillet. 1902. Ent. News 13:85

LARVA: n = 8

Antenna: First segment 278.5 (255-305.7) um long; antennal

ratio 7.24 (6.8-7.85). Ring organ 208.9 (187.2-231.7) um

from base of first segment. Antennal blade reaches to

midpoint of third segment.

Prementohypopharyngeal complex: Ligula with light colored

teeth, outer teeth splayed slightly; length 127.0

(117.5-139.0) um, width 67.5 (60.0-75.9) um. Paraligula 69.7

(63.3-77.5) um long; two main branches each distally bifid

plus one small outer tooth. Pecten hypopharyngis with 18 or

more long teeth. M-appendage about 125 um long, pseudoradula

distinct. Dorsomentum with six or seven teeth in a slightly

57

concave plate, most lateral teeth small.

Mandible: Length 246.4 (224.0-269.5) um; apical dark, inner

teeth six or more.

Maxillary palp: A single basal segment 67.2 (58.2-72.5) um

long.

Body: Procerci about 3.5 times longer than wide, with 18 or

more anal setae. Some of the larger claws on the posterior

parapods have small spines on the inner margin.

PUPA: n = 4

Color: Dark brown. Each abdominal segment has an anterior

dark line.

Length: Total length, 7.6 (7.1-8.0) mm; abdominal length 5.6

(5.3-6.0) mm.

Cephalothorax: Thoracic horn 607.5 (570.0-650.0) um long,

192.3 (172.6-221.9) um wide, slightly flared distally,

plastron plate small on terminal surface; surface with small

spines.

Abdomen: Scar on tergite I approximately circular with a

deep posterior notch. Sparse uniform shagreen on tergites II

to VIII. Lateral setae on segments VI-1, VII-6 or 7, VIII-5.

Anal lobes 1020 (970-1050) um long, two macrosetae in

anterior:hai� of each lobe.

BIOLOGICAL NOTES: Larvae were collected from the shallow

benthos in pond·A and the culvert inflow of pond B. The

digestive tracts contained diatoms, detritus, ostracods,

orthoclads, cladocerans and coleopteran or trichopteran

....

58

remains.

Psectrotan� g�ari is tolerant of a wide range of

ecological conditions (Roback 1971).

REMARKS: Reared males keyed easily in (Roback) 1971.

However the measurements and ratios of the immatures were

much larger than those given for E. near dyari, but Roback

(1978) mentions that specimens from higher latitudes are

often larger.

DISTRIBUTION: Psectrot�� g�ri is the most widespread

and abundant species in the subtribe Macropelopia (Roback

1971). It has been collected from BC, MB, ON, PQ, SK, and YT

in Canada. In the United States it is known from CA, CO, CT,

DC, FL, IL, lA, KS, KY, MI, MN, MS, MT, NV, NH, NJ, NY, PA,

RI, SC, SO, TN, UT, WV, WA, WY. (Roback 1978, Driver 1977,

Roback 1971).

MATERIAL EXAMINED: Pond A: 2 reared males, reared female

from pupa, pupal exuvium, larva. Pond B: 5 larvae. Pond F:

larva.

Tanypu§ Meigen

Meigen. 1803. Mag. F. Insektenkunde: 261

LARVA: Large from 10 to 12 mm. Antennae four segmented,

slightly longer than mandibles. Ligula with five teeth,

anterior margin straight or concave. Dorsomentum with five

or six teeth on each side. M appendage divided into five

lobes. Paraligula large, with two to nine long apical and

.....

.....

59

lateral branches. Pecten hypopharyngis reduced. Maxilla

with a single basal segment. Mandibles with enlarged base

and two or three inner teeth. Anterior parapods with a crown

of claws. Abdominal segments fringed with setae. Procerci

about five times longer than wide.

PUPA: Thoracic horns saclike. Scar on tergite I absent.

Shagreen on tergites as fine spinules. Lateral setae on

abdominal segments variable in number. Anal lobes small and

rounded with a pair of anal setae.

REMARKS: Roback (1971) divided �� into two subgenera;

Tanypus (s. str.).and I. (�lopi�) based on adult

characters.

Larvae of Ianypus prefer the soft sediments of shallow,

warm, lentic and lotic waters (Oliver and Roussel 1983).

Some species can tolerate a variety of environmental

conditions including organic pollutation (Oliver and Roussel

1983). The larvae feed on chironomid larvae, plant material

and algae (Fittkau and Roback 1983).

The genus has a world wide distribution, 11 species are

known from the Nearctic (Fittkau and Roback 1983).

One species was collected in this study.

Tanypus (�nypus) punctipennis Meigen

(Figures 44 to 47)

Meigen. 1818. Forstman Aachen:61

LARVA: n = 1

Antenna: First segment 190.0 urn long, antennal ratio 6.9.

......

60

Ring organ 142.5 um from base of first segment. Antennal

blade 12.5 um long.

Prementohypopharyngeal complex: Ligula with five light brown

teeth with a convex anterior margin; length 80 um, width 27

um. Paraligula 65.0 um long, made up of five branches, the

medial two branch 0.46 from base. Pecten hypopharyngis

greatly reduced, with two or three medial teeth. M-appendage

obscured, appears to have five lobes. Dorsomentum composed

of six lateral teeth in a concave plate, first lateral teeth

appressed to median tooth.

Mandible: Length 110 um. Apical tooth light brown. Base

greatly enlarged.

Body: Procerci four times longer than wide, bearing 16 anal

setae. Claws of posterior parapods simple, none with

expanded bases.

PUPA: No pupae were collected.

BIOLOGICAL NOTES: The single specimen was collected from a

culvert flowing into pond B on June 28, 1983.

Larvae are indifferent to pH, tolerant to low oxygen

levels, and can live on the substrate or be freeliving (Beck

1977).

REMARKS: The. larval specimen:keys easily in Roback (1977).

DISTRIBUTION: The species has been reported from BC, MB, ON,

and SK in Canada, and from CA, FL, GA, IL, MD, MA, MI, NJ,

NY, NE, NV, PA, SO, WA, and WI in the United States (Roback

1977, Roback 1971).

61

MATERIAL EXAMINED: Pond B: 1 larva.

....

62

CHIRONOMINAE

LARVA: Color ranges from white to green to dark red. Size

from small to large.

Antennae: Five to eight segmented. In the tribe Chironomini

the antennae are directly articulated to the head capsule,

but in the ttibe Tanytarsini the �ntennae are articulated on

antennal tubercles. Ring organ present on the first antennal

segment. Antennal blade usually shorter than combined

lengths of terminal segments, accessory blade much shorter

than blade. Lauterborn's organs of the Chironomini are

usually sessile on the second antennal �egment and very

small. In the Tanytarsini the Lauterborn's organs are

sometimes large and located on the apex of petioles of

varying lengths.

Labrum: 51 variable, in the Tanytarsini bases are fused or

almost fused. 511 usually simple. Pecten epipharyngis made

of three toothed scales or a single toothed bar.

Premandibles almost always present, with one to seven teeth

and often with a well developed premandibular brush.

Mentum: With nine to sixteen anteriorly directed teeth.

Ventromental plates well developed with distinct striations.

Mandibles: With an apical tooth and often a distinct dorsal­

tooth. Inner margin usually has three to five inner teeth.

Pecten mandibularis, seta subdentalis and seta interna are

all usually present.

Body: Anterior parapods usually separate with a crown of

......

63

claws on the apex of each parapod. In some species of

Chironomini the eighth abdominal segment has a pair of

lateral tubules and none, one or two pairs of ventral tubules

on the ninth segment. Procerci usually well developed with a

number of anal setae. Two pairs of anal tubules usually

present. Apex of each posterior parapod with a number of

strong claws.

PUPA: Size 3 mm to 20 mm long. Color green to red or brown.

Cephalothorax: Thoracic horns of the Chironomini are usually

plumose or a number of wide lumened branches. In the

Tanytarsini the thoracic horns are a single tube or absent.

The cephlic tubercles are variably developed, frontal setae

may be present or absent. The dorsal surface may be nodulose

or slightly wrinkled.

Abdomen: In the Chironomini the abdominal tergites may have. .

a uniform or patchy shagreen pattern. Tergite II usually has

a hook row which may be interrupted medially. Pedes spurii 8

on segment II may be present or absent. A variable number of

lateral setae are present on segments V to VIII. Segment

VIII often has a variably developed spur. The anal lobes

have hair fringe.

The abdominal tergites of the Tanytarsini may have paired

spine patches present, which in a few cases are fused

medially. The spur of segment VIII is usually well

developed. The anal lobes have a well developed hair fringe.

64

KEY TO CHIRONOMINAE GENERA

collected in study

LARVAE

1a. Antennae on tubercles (Fig. 128). Ventromental

plates closely appressed together medially (Fig.

131 ) ••••••••••••••••••••••••• �anytarsini ••••••••• 10

1b. Antennae not on tubercles. Ventromental plates

separated by at least width of median tooth or

teeth of mentum(Fig. 120) •••• Chironomini •••••••••• 2

2a. Premandibles with six teeth (Fig. 79) ••••••••••••••

• • • • • • • • • • • • • • • • • • • • •• •• • • • • • • • • • • • Cryptochir.!2!:!.2.!!!Us2b. Premandibles bifid (Fig. 65) •••••••••••••••••••••• 3

3a. Sixth lateral tooth of mentum enlarged (Fig. 75) •••

•• •• • • • • •• • • •• •• •• • • • • • • •• •• •• •• • • • • • • •• • Cladonelma--�-

3b. Sixth lateral tooth of normal size (Fig. 53) •••••• 4

4a. Mandibles with two distinct inner teeth (Fig 117) ••

•••••••••• •••• •• •••••• •• •• •••••••••• • �chironomus

4b. Mandibles with two or three inner teeth (Fig. 121)5

5a. Mentum with an even number of teeth (Fig. 120) •••• 7

5b. Mentum with an odd number of teeth (Fig. 54) •••••• 6

6a. Median tooth distinctly trifid (Fig. 54 •• Chironomus

6b. Median tooth simple (Fig. 88) ••••••••••••••••••••• 8

7a. Pecten epipharyngis divided into three scales

(Fig. 98) •••••••••••••••••••••••••••• Endochironomus

7b. Pecten epipharyngis appearing as a single plate·

with long teeth (Fig. 119) ••••••••••••�enop��

-

1a. Thoracic horns simple tubes (Fig. 133). Tergites

65

8a. Pecten epipharyngis with five or fewer teeth •••••••

•••••••• •••• •••• •••••• •••••••••• •• •••• Dicrotendines----------,----.�---

8b. Pecten epipharyngis with ten or more teeth

(Fig. 56) •.••••••••••••••••••••••••••••••••••••••• 9

9a. Frontal apotome with a circular depression (Fig 92)

••••••••••••••••••••••••.................... Ei�ldia9b. Frontal apotome without a circular depression ••••••

• • • • • • • • • • • • • • • • • • • • • • • • • • •• • • • • • • • • •�totendiE�

10a.Petioles of Lauterborn organs longer than the

combined lengths of the third to fifth antenna 1

segments (Fig. 136) •••••••••••••••••••••• Tanytarsus

10b.Petioles of Lauterborn organs shorter than

combined lengths of the third to fifth antennal

segments (Fig. 122, 128) ••••••••••••••••••••••••• 11

11a.Middle tooth of mentum notched laterally (Fig. 125)

•••••••••••••••••••••••••••••••••••• Cladotanyta�'us11b.Middle tooth of mentum simple (Fig. 131) •••••••••••

• • • • • • • • • • • • • • • •••• • • • • • • • • • • • • • • • • • • E��.!::!X t a��

PUPAE

with paired spine tracts (Fig. 134) •••••••••••••••

•••••••••••••••••••••••••••••••••• Tanytarsini •••••••• 11

1b. Thoracic horns tufts of fine filaments or a number

of larger tubules. Tergites not as above ••••••••••

••••••••••••••••••••••

·

•••••••• Chironomini ••••••••• 2

2a. Thoracic horns a series of tubules •••• Eha�£E�£1!�

-

-

66

2b. Thoracic horns a tuft of fine filaments ••••••••••• 3

3a. Caudolateral corner of segment VIII without a

distinct spur (Fig. 112) •••••••••••••••••••••••••• 4

3b. Caudolateral corner of segment VIII with a distinct

variable spur (Fig. 59, 71) ••••••••••••••••••••••• 7

4a. Tergites pale yellow or dark amber. Anal lobes

with central forked process (Fig. 83) ••••••••••••••

•••• •• •••••• •••••• •• •• •• •• •• •••••• • Crlltochi.£Q!!�

4a. Tergites dark brown. Forked process absent ••••••• 5

Sa. Mace-like processes present on one or more tergites

(Fig. 74, 110, 111) 6

5b. Tergites without mace-like processes ••••••.•••••••• 7

6a. Tergites II or III to VI with medial mace processes

(Fig. 110, 111) •••••••••••••••••••••• Glx.Etotendipes

6b. Mace process present on tergite ·VI only (Fig. 74) ••

• • • • • •

'

••••••••••••••••••••••••••••••••••• C lad.2.E�

7a. Hair fringe on anal lobes uniform (Fig. 57) •••••• 8

7b. Hair fringe with dark caudal tufts (Fig. 104) ••••••

•• •• • ••• •• •• • ••• •••• •• •• •• •• •••• ••••• En�chironomus

8a. Segments II to VI with three transverse bands of

shagreen. On segement II the posterior band is

u - s hap e d • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 0 i .E.!:!2� n d i p�

8b. Shagreen more uniform (Fig. 70, 72) ••••••••••••••• 9

9a. Spur on segment VIII large (Fig. 59, 69, 71) •••••••

•• •• •• •• •••••••.••••• •••••• •• •••• •••• ••••• Chironomus

9b. Spur small or absent (Fig. 95, 112, 113) ••••••••• 10

67

10a.Spur small, usually one or two spines, sometimes

branched (Fig. 95). Shagreen increases in size

medially and caudally on tergites IV, V, VI

(Fig. 96) ••••••••••••••••••••••••••••••••• Einfeldia

10b.Spur absent, if present, larger with more spines.

Shagreen not as above (Fig. 11,2, 113) •

• ••• •• •••• •• •••• •• •••••••••••••• •••• ·E�chironomus

11a.Spine tracts on abdominal tergites laterally placed,

never joined medially (Fig. 134) ••••••••••••••••• 12

11b.Spine tracts on segments IV and V single or paired

close to midline ••••••••••••••••••••• Parata�tars�

12a.Segments II to IV with paired longitudinal spine

tracts. Segment VIII with a spur of eight or fewer

teeth ••••••••••••••••••••••••••••••• Cladotanyta�

12b.Spine tracts on segments III to VI (Fig. 134, 135).

Spur on segment VIII ·with eight to ten fine teeth ••

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Ta���

Chi£2�� Meigen

Meigen. 1803. Mag. f. Insectenkunde 2:260

LARVA: Antennae five segmented. Median tooth of mentum

trifid with six pairs of lateral· teeth. Ventt���ri�al plates

usually smooth on anterior margin, with striations.

Mandibles with two or three inner teeth, dorsal tooth and.

pecten mandibularis present� inner margins with spines. SI

and SII usually pectinate. Premandibles usually bifid.

-

....

68

Pecten epipharyngis a simple bar with 10 to 20 teeth along

posterior margin. Anterior and posterior parapods separate

each with a crown of claws. Seventh abdominal segment with

posterior lateral process present or absent. Abdominal

segment eight with two pairs of ventral tubules present or

absent.

PUPA: Cephalic tubercles with frontal seta present.

Thoracic horns plumose. Hook row on tergite II complete.

Abdominal tergites with variable shagreen patterns.

Conjunctives bare or with small spinules present. Lateral

setae, V-4, VI-4, VII-3 or 4, VIII-5. Spur on segment VIII

made of one to twenty spines. Anal lobes with well developed

hair fringe.

REMARKS: fbl��� has a world wide distribution consisting

of several hundred species. The three subgenera known from

the Holarctic, Chironomus (s. str.); f. (Ca�tochir���)and f. (Chaetaboli�) cannot be separated in the larval stage

(Pinder and Reiss 1983), but recent work by Webb et. ale

(1985) has shown that some European Chi£2�� larvae can be

identified to species using morphological characters. f.

(Camptochironomus) has been considered by some workers as a

separate genus (Ashe 1983, Pinder and Reiss 1983). However

this has not been generally accepted by taxonomists.

Larvae of Chi��� are found in all types of freshwater

habitats, especially in eutrophic conditions (Wilson and

McGill 1982). They are most common in lentic environments

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Chi .!:!2!J�'§' atrella----

69

and the slower areas of lotic habitats (Oliver and Roussel

1983). The larvae feed on detritus by deposit feeding and/or

filter feeding (Pinder and Reiss 1983).

Four species were collected in this study.

Key to species of Chironomus

LARVAE:

1a. Large. Antennal ratio more than 2.5. First

antennal segment longer than 152 urn. Mandible

longer than 250 um •••••••••••••• Chironomus tenta�

1b. Larvae smaller in all measurements •••••••••••••••• 2

2a. Antennal ratio about 1.9. First antennal segment

125 urn long. Mandible 248 urn long •••••••••••••••••

2b. Antennal ratio about 1.75. First antennal segment

137 urn long. Mandible 225 urn long ••••••••••••••••••

Ch'..

• •••••••••••••••••••••••••••••• _'!!.E.!J.2'!!!� .!: 1. par 1. !:!.§.

PUPAE:

1a. Exuvium large about 12 mm long. Dark brown •••••••••

•••••••••••••••••••••••••••••••• Chi.!.2nomus tentans

1b. Exuvium smaller and paler ••••••••••••••••••••••••• 2

2a. Exuvium about 11.8 mm long. Anterior and lateral ••

margins of tergites II to VI without shagreen ••••••

• •••••••••••••••••••••••••••••••••••• f.b.!ronomus sp ,

2b. Exuvium small�r, under 9 mm long •••••••••••••••••• 3

3a. Exuvium length about 7.6 mm •••••• Chironomus �trel�

3b. Exuvium length about 8.08 mm •••• Chlronomu.§. ripari�

-

70

Chironomus (s. str.) ��la Townes

(Figures 48 to 52, 60)

Townes. 1945. American MidI. Nat. 34:124

LARVA: n = 5, unless otherwise stated.

Antenna: First segment 125.0 (12�.5-127.5) um long; antennal

ratio 1.9 (1.7-2.2). Ring organ 42.3 (30.0-53.8) um from

base of first segment. Antennal blade reaches to mid-point

of fourth segment. Lauterborn's organs reduced, sessile on

the apex of segment two.

Labrum: SI pectinate, SII simple, about 1.5 times as long as

SID Pecten epipharyngis made up of a bar with .14 teeth.

Premandibles bifid.

Mentum: Thirteen teeth, median tooth distinctly trifid;

first two laterals partially fused. Ventromental plates

200.3 (192.5-208.8) um long, 59.5 (�6.3-62.5) um wide;

posterior band of strong striations, anterior surface smooth.

Mandible: Length 248.8 (242.5-252.5) um. One dorsal tooth

present; apical tooth and first two inner teeth dark, third

tooth pale. Seta subdentalis short·. Seta interna well

developed with four major branches. Pecten mandibularis well

developed. An arc of crenulations is present on the base.

Two or three spines are present on the inner margin.

Body: Anterior parapods separate, each with a apical crown

of claws. Abdominal segments destroyed. Procerci with six

anal setae. Posterior parapods separate, each with a crown

.....

....

71

of simple claws.

PUPA: n = 5, unless otherwise stated.

Color: Brown.

Length: Total length 7.7 (7.3-B.1) (n = 4) mm, abdominal

length 6.0 (5.7-6.2) (n = 4) mm.

Cephalothorax: Cephalic tubercle� acute, apex appears

slightly cupped; a preapical frontal seta is present. Dorsal

surface covered with nodulations.

Abdomen: Hook row on tergite II complete, extending almost

the total width of the segment. Pedes spurii B present on

segment II. " Tergites II, III, IV, V, and VI with shagreen

absent in the anterior part, shagreen increases toward the

posterior of each tergite, as well as caudally. Tergite VII

with two areas of sparse shagreen in the anterior porti6n of

the segment separated medially. Tergite VIII with paired

shagreen areas in the posterior part, separated medially.

Lateral setae V-4, VI-4, VII-4, VIII-5. Spur on segent VIII

dark brown, made of 3 or 4 spines. Anal lobes with a hair

"fringe of 75 or more hairs per lobe.

BIOLOGICAL NOTES: Specimens examined were collected as

larvae from the benthos of the shallow areas of pond A during

mid August to September in 1983.

Larvae of Chironomus atrella have been found in a wide

range of aquatic habitats from small ponds and reservoirs to

lakes, rivers and coastal coves (Gillespie" 1974; Anderson and

Hitchcock 1968).

72

The biology of the species has been studied in

association with a mixohaline cove in Connecticut (Anderson

and Hitchcock 1968).

REMARKS: The five reared male specimens key to Chlronomu�

atrel� in Townes (1945) and Gillespie (1974). Gillespie's

descriptions of the larvae and pupae agree with my material

except in the antennal ratio of the larvae, the length of the

antennal blade and the number of lateral setae on the eighth

abdominal tergite of the pupae.

I was unable to find any significant differences between

the immature stages of Chir£�� !lEari� and f. at�la to

separate all specimens of these two species I examined. The

characters in the key should be used with caution.

DISTRIBUTION: Chir�� �tr� has not previously be

reported from Saskatchewan. It has been collected from AB,

MB, and PE in Canada; and from CA, CO, MA, MN, NV, and SO, in

the United States (Gillespie 1974, Sublette and Sublette

1965, Johannsen and Townes 1952).-

MATERIAL EXAMINED: Pond A: 5 reared males.

Chironomus (s. str.) rip�ius Meigen

(Figures 53 to 59, 61)

Meigen. 1804. Etster Band. �pt�- I�13

LARVA: n = 2, unless otherwise stated.

Antenna: First segment 136.0-137.5 um long; antennal ratio

1.7-1.8. Ring organ 43.8 (n=1) um from base of first

segment. Antennal blade reaches to apex of fourth segment.

73

Lauterborn's organs sessile on apex of second segment.

Labrum: SI pectinate; SII simple, about 1.5 times the length

of SI. Pecten epipharyngis with 13 teeth. Premandible

bifid.

Mentum: First two lateral teeth partially fused.

Ventromental plates 177.5-197.5 u� long, 55.5-57.5 um wide;

posterior band of strong striations, anterior edge smooth.

Mandible:. Length 222-225 um. One pale dorsal tooth, apical

and two inner teeth dark. Third inner tooth pale, may be a

pseudotooth. seta interna with four main branches. Pecten

mandibularis well developed. Seta subdentalis short. Base

with an arc of grooves. Inner margin with two or three

spines.

Body: Seventh abdominal segment does not have posterior

lateral tubules, eighth abdominal segment bears two pairs of

ventral tubuli (Bryce and Hob�rt 1972; Simpson and Bode

1980). Procerci short, bearing 7 anal setae •.

PUPA: n = 2, unless otherwise stated.

Color: Light brown.

Length: Total length 7.4-7.9 mm, abdominal length 5.6-6.3

mm.

Cephalothorax: Cephalic tubercles acute, 103 (n = 1) um

long, with preapical frontal seta. Dorsal surface covered by

fine nodulations.

Abdomen: Segment II with pedes spurii B present. Anterior

portion of tergites II, III, and IV bare. Tergites V and VI

74

are uniformly covered by shagreen. Tergite VII has an

anterior band of sparse shagreen. Tergite VIII has two

medial patches of sparse shagreen, spur appears to be one

spine. Lateral setae V-4, VI-4, VII-4, VIII-5. Anal lobe

with 75 hairs or. more on each lobe.

BIOLOGICAL NOTES: The larvae of the two reared males were

collected from pond A on July 27, 1983. The immature stages

inhabit lentic and lotic conditions (Beck 1977; Gillespie

1974; Simpson and Bode 1980). Larvae tolerate high levels of

organic pollution and may have potential as a pollution

indicator (Paine and Gaufin 1956). The larvae live on or in

the substrate feeding on dead plants or animals (Beck 1977).

REMARKS: The reared adult males key in Townes (1945),

Gillespie (1974), Edwards (1929) and Pinder (1978).

Gillespie (1974) describes the immature stages of the

species. The pupal exuviae of the collected material has one

more lateral seta on VII and VIII than Gillespie's·material.

Immature specimens of this species could not be

distinguished from those of Chironomus atrella unless reared

to adult males. The immature keys should be used with

caution.

DISTRIBUTION: Chir��� ri£arius is a Holarctic species.

In North America it inhabits· the continent from Alaska to

Newfoundland south to California and Florida (Gillespie

1974).

MATERIAL EXAMINED: Pond A: 2 reared males.

75

Chironomus (famptochiron��) te�tan� (Fabricus)

(Figures 62 to 71)

Fabricus. 1805. Systema antiliatorum secundum ordines,

genera, species Brunswick: 38.

LARVA: n = 8, unless otherwise stated.

Antenna: First segment 159.8 (152.0-171.5) (n=6) um long;

antennal ratio 2.6 (2.5-2.8) (n=4). Ring organ 51.4

(41.7-57.8) (n=6) um from base of first segment. Antennal

blade slightly longer than terminal segments. Lauterborn's

organs reduced.

Labrum: SI pectinate; SII simple, about twice as long as SI.

Pecten epipharyngis with 12 to 14 teeth. Premandibles bifid.

Mentum: First two laterals partially fused. Ventromental

plates 252.1 (230.0-274.4) um long and 73.2 (68.6-78.4) um

wide; anterior margin smooth, posterior band of striations

distinct.

Mandible-: Length 296.4 (264.6-328.5) urn. One pale dorsal

tooth, apical tooth and two inner teeth dark. Pecten

mandibularis, well developed. Seta subdentalis short. Seta

interna made up of three main branches, each of which is

further subdivided. Basal area of mandible has an arc of

grooves. Two or three spines present on the inner margin.

Body: Seventh abdominal segment with a posterior lateral

process. Eighth abdominal segment has a pair of ventral

tubules. Procerci short with 7 anal setae.

PUPA: n = 9, unless otherwise stated.

76

Color: Dark brown.

Length: Total l�ngth 12.0 (11.4-13.1) (n=8) mm; abdominal

length 9.2 (8.8-10.0) mm.

Cephalothorax: Cephalic tubercles acute with a frontal seta.

Dorsal surface nodulate.

Abdomen: Segment II with Pedes spurii B present. Segments

II to VI and VIII with uniform shagreen, progressively

increasing in size in the posterior of each segment.

Shagreen of VII reduced to anterior portion only. Lateral

setae, V-4, VI-4, VII-3, VIII-5. Segment VIII with a dark

b�own spur made of about five spines fused together. Anal

lobe with a hair fringe of about 50 hairs on each lobe.

BIOLOGICAL NOTES: This species was very abundant in pond A.

The immatures were collected from the central benthos region

of the pond. Gut 'contents of the larvae were mostly

detritus. The peak emergence period in pond A was from June

to mid July 1983 and 1984.

REMARKS: The reared males keyed easily in Townes (1945).

Larvae of .£. tent..2!!.2 were the only species collected, from

pond A, with two ventral tubules.

DISTRIBUTION: The species is Holarctic and widespread in

North America (Sublette and Sublette 1965).

MATEERIAL EXAMINED: Pond A: 9 reared males; 2 reared

females; 3 larvae associated with pupae; 37 pupal exuviae; 65

larvae.

Chironomus sp

77

\

(Figures 72, 73)

Larvae: No larvae were associated.

Pupa: n = 4

Color: Cephalothorax dark brown, abdomen pale.

Length: Total length 11.8 (11.3-12.2) mm; abdominal length

9.3 (8.9-9.6) mm.

Cephalothorax: Cephalic tubercles conical, acute with a

short preapical frontal setae. Dorsal surface with nodules.

Abdomen: Tergite I bare. Pedes spurii B present on segments

I and II. Hook row on tergite II complete, about as wide as

segment. Tergites II to VI with lateral and anterior margins

bare, and a central shagreen patch. Conjunctives bare.

Tergite VII with a pair of anterior shagreen patches.

Tergite VIII with a pair of posteriolateral shagreen patches.

Lateral setae VIII-S, VII-4, VI-4, V-4. Spur on segment VIII

well developed, made of about ten spines. Anal lobes with

extensive hair fringe.

BIOLOGICAL NOTES: Pupae were collected in late July 1984

from pond A.

REMARKS: The pupal exuviae key to Chironomus ���� group

in Wilson and McGill (1982); f. �£� in Mason (1983); and

f. nr sta��l ? in Mason (1978). Reared material will be

required to identify the specimens to species.

MATERIAL EXAMINED: Pond A: 4 pupal exuviae.

Cladopel�� Keiffer

,-78

Kieffer. 1921. Bull. Soc. Hist. nat. Metz. 29:63

LARVA: Antenna five segmented. Mentum usually with two

medial teeth, or a notched single median tooth, and five

pairs of lateral teeth, most lateral teeth enlarged.

Ventromental plates narrow. SI simple. Pecten epipharyngis

with a long medial scale and two �horter toothed scales.

Premandibles with four to six teeth. Mandibles with two

inner teeth, dorsal tooth and pecten mandibularus absent.

Ventral tubules on abdominal segment eight absent. Procerci

present.

PUPA: Exuviae pale. Thoracic horns plumose. Cephalic

tubercles with spinules. Conjunctives III/IV and IV/V with

spinules. Tergite VI with a mace-like process on the

posterior margin. Segment VIII with a single or double,

thin, pale spine laterally.

REMARKS: CI�doeelma belongs to the Harnischl� complex

(Saether 1977). Most species are unknown or inadequately

described as larvae (Pinder and Reiss 1S83).

Larvae inhabit sandy or muddy substrates of shallow

lakes and rivers (Oliver and Roussel 1983, Pinder and Reiss

1983). Some species are tolerant to low oxygen levels

(Wilson and McGill 1982).

CI�doeelma has been reported from the Holoarctic and

Afrotropical regions (Pinder and Reiss 1983). About 17

species have been reported from the Holarctic (Pinder and

Reiss 1983), and seven from the Nearctic (Oliver 1981). In

79

Canada the genus is known from British Columbia and Yukon

Territory to Quebec (Oliver and Roussel 1983).

In this study larval and pupal stages were collected

which may be the same species or two species.

Cladopelm� sp. 1

(Figure 74)

LARVA: None were associated.

PUPA: n = 1.

Color: Pale yellow brown.

Length: Total length 4.5 mm, abdomen length 3.4 mm.

Cephalothorax: Cephalic tubercles acute, 63.3 urn long with

very minute apical spinules. Dorsal surface sparsely

nodulated.

Abdomen: Tergite I with medially paired patches of pale

spines. Tergite II with an anterior band of stout pale

spines. Hook row on segment II consisting of about 50 hooks,

medially interrupted. Tergites III to VI with uniform,

sparse points, and a posterior row of points. Tergite VI has

a toothed posteriomedial mace-like process. Tergites VII and

VIII almost bare. Lateral setae, VIII-4, VII-4, VI-4, V-3 or

4. Caudolateral corner of VIII with a single, thin pale

spine set lateraliy on the s����nt. Anal lobes with hair

fringe of about 50 hairs.

BIOLOGICAL NOTES: The single specimen was collected from

pond A on June 15, 1983.

REMARKS: The specimen does not fit any of the species

,

80

descriptions provided by Beck and Beck (1969). The specimen

keys to CI�doRelma in Wilson and McGill (1982). The female

is in very poor condition, other associated material will be

needed for species identification.

MATERIAL EXAMINED: Pond A: female associated with pupa.

CladoR'!u:� ,sp. 2

(Figures 75 to 77)

LARVA: n = 1

Antenna: First segment 62.0 urn long, terminal segments 41.0

urn long, antennal ratio 1.5. Third antennal segment half as

long as fourth segment. Ring organ 15.0 urn from base of

first segment. Antennal blade 5.5 urn long.

Labrum: SI and SII simple, SI half as long as SII. Pecten

epipharyngis a simple plate. Premandible unevenly bifid,

with well developed brush.

Mentum: Thirteen teeth, median tooth notched in the middle,

sixth lateral tooth enlarged, three times larger than fifth

lateral. Ventromental plates twice as long as wide,

striations very distinct in the posterior half.

Mandible: Length 127.0 urn. Apical tooth light brown. Two

inner teeth broad and flat. Seta interna with three main

branches, two not subdivided but pectinate at apex., Seta

subdentalis 22.0 urn long. Dorsal tooth absent.

Body: Anterior parapods separate with a crown of claws.

Procerci short, with eight anal setae. Posterior parapods

with simple claws.

1--,

81

PUPA: None were associated.

BIOLOGICAL NOTES: The larval specimen was collected from an

algal mat in pond A in 1982. The digestive tract of the

larva contained detritus and a number of diatoms.

REMARKS: Cladopelma is described as Harns� in Beck and

Beck (1969). The larval specimen ,fits the description for

.!:!arnischia galeat£_E in Beck and Beck (1969). The specimen

keys to f. late�lis group in Pinder and Reiss (1983). More

material is needed to positively identify the specimen.

MATERIAL EXAMINED: Pond A: larva.

f!1ptochiro�� Kieffer

Kieffer. 1918. Ent. Mitt. 7:46

LARVA: Antennae five segmented. Mentum with single light

colored, dome shaped medial tooth and five pairs of lateral

teeth arched antereomedially. Ventromental plates narrow.

SI and SII simple. Pecten epipharyngis a triangular plate

divided into three lobes, posterior margin serrated.

Premandibles with four to six apical teeth. Mandibles with

two inner teeth. Seta interna and seta subdentalis present.

'Dorsal tooth and pecten mandibularis absent. Procerci

present. Ventral tubules absent.

PUPA: Cephalic tubercles may be large and often with a

distinctive shape. Thoracic horns plumose. Hook row on

tergite II interupted medially. Tergites yellow or amber

with cuticular recticulations. Tergites III to VIII with a

,-82

posterior transverse row of short strong spines. Segment

VIII lacking a spur. Anal 'lobes with a medial cuticular

projection between the lobes.

REMARKS: Cr1Btochironomus belongs to the Harnischi� complex.

Larvae inhabit shallow areas of lentic and lotic

conditions (Oliver and Roussel 19�3). They are tolerant to

low levels of oxygen (Wilson and McGill 1982).

The genus is distributed throughout the world, with about

30 species known from the Holarctic (Pinder and Reiss 1983).

Six species are known from the Nearctic (Oliver 1981).

One species was collected in this study.

Cr1Etochironomus digitatu� Malloch

(Figures 78 to 84)

Malloch. 1915. Ill. State. Lab. Nat. Hist. Bull. 10:4B3

LARVA: n = 1

Antenna: First segme�t 80.0 urn long, antennal ratio 0.9.

Third segment subequal to second. Fourth and fifth segments

subequal. Ring organ 55.0 urn from base of first segment.

Labrum: SII twice as long as SI. Pecten epipharyngis a

serrated scale with median tooth longest. Premandibles with

six teeth.

Mentum: Thirteen teeth, median tooth light, six lateral

teeth obliquely pointing inwards making mentum appear

concave. First laterals closely apressed to median tooth,

sixth laterals notched on the apex. Ventromental plates

240.0 urn long, and 48.0 urn wide; striations very distinct.

83

Mandible: Length 235.0 um. Apical tooth and two inner teeth

dark' brown. Seta i�terna with three main branches. Seta

subdentalis 33.0 um long.

Body: Anterior parapods separate with a crown, of claws.

Posterior part of, abdomen missing.

PUPA: n = 3, unless otherwise st�ted.

Color: Yellow.

Length: Total length 15.1-15.8 (n = 2) mm; abdominal length

11.2-11.6 (n = 2) mm.

Cephalothorax: Cephalic tubercles 490.0 (n=1) um long,

acute, frontal seta absent. Entire surface of the

cephalothorax covered by nodulations.

Abdomen: All segments with very distinct recticulations.

Pedes spurii 8 present on segment II. �ow of points on

tergites III, IV, V, VI, and VII. Intersegmental

conjunctives with fine spinules. Shagreen on the tergites

sparse or absent. Four lateral setae on segments V to VIII.

Anal lobe with a hair fringe of 70 or more hairs per lobe,

and a medial bifurcated appendage.

BIOLOGICAL NOTES: The pupal specimens were collected in June

1983. Food consists of organic detritus, diatoms, algal

spores, and chironomid larvae (Curry 1958).

REMARKS: The specimens key easily in Mason (1983) and Curry

(1958).

DISTRIBUTION: Saskatchewan to Ontario and Maine, south'to

Texas, Georgia and California (Sublette and Sublette 1965).

84

MATERIAL EXAMINED: Pond A: 2 pupal exuviae and a pupa with

associated larval exuvium.

Dicrotendie� Kieffer

Kieffer. 1913. Voyage de Ch. Allmand et R. Jeannel en Afrique

orientale 5:23

LARVA: Antennae five segmented. Mentum with a single median

tooth and six pairs of lateral teeth. Ventromental plates

narrow, striated, anterior margin smooth or crenulate. SI

plumose, SII simple. Pecten epipharyngis a plate with three

to seven teeth. Premandibles bifid. Mandibles with three

inner teeth. Dorsal tooth, pecten mandibularis, seta interna

and seta sub dental is present. Procerci present. Ventral

tubules absent.

PUPA: Cephalic tubercles acute. Thoracic horns plumose.

Tergite II with hook row complete. Pedes spurii present 'on

IV and/or V. Tergites II to VI with variable shagreen

patterns. Conjunctives bare. Four lateral setae are present

on segments V, VI, VII, VIII. Spur on segment VIII made up

of several spines. Anal lobes with 25 to 90 hairs on each

lobe.

'REMARKS: The' Lmmatu r e s usually inhabit the littoral

sediments of lentic habitats (Pinder and Reiss 1983). They

are tolerant of low oxygen levels (Wilson and McGill 1982).

The genus has a world wide distribution. Twenty species

are known from the Holarctic (Pinder and Reiss 1983). Nine

�-

,85

LARVA: n=3

Antenna: First segment 75.4 (68.8-80.0) urn long, antennal

ratio 1.25 (1.2-1.29). Fourth segment four times as long as

wide. Ring organ 19.2 (16.3-21.3) urn from base of first

segment. Antennal blade reaches to midpoint of fourth

segment.

Labrum: SI plumose; SII simple, one and a half times the

length of sr. Pecten epipharyngis a plate with four or five

large teeth. Premandible bifid.

Mentum: Middl� tooth simple, same length as first laterals,

fifth and sixth laterals fused together. Ventromental plates

widely separated; length 105.8 (105.0-107.5) urn, width 40.8

(37.5-42.5) urn; striations prominent ��sely, becoming less

prominent anteriorly, anterior margin minutely crenulate.

Mandible: Length 199.2 (197.5-200.0) urn. Three inner teeth

and one dorsal tooth. Pecten mandibularis well developed.

Seta subdentalis reaches apex of third inner tooth. Seta

interna with' three major branches.

8ody: Anterior parapods separate, each with a crown of

claws. Procerci small, with 7 anal setae. Four anal tubules

species are reported from the Nearc�ic (Oliver 1981). In

Canada the genus is widespread south of treeline (Oliver and

Roussel 1983).

One species was collected in this study.

Dicrotendi� sp.

(Figures 85 to 89)

r

86

present. Posterior parapods with simple claws.

PUPA: No pupae collected.

BIOLOGICAL NOTES: The larvae were collected from submerged

decaying Sali� branches on July 25, 1983.

R�MARKS: The larvae keys easily in Mason (1983) to Q.

nervosus. In Simpson and Bode (1Q80) it keys to

Dic££�dipes ���1 Type II. Reared material will be

needed to confirm this identification.

MATERIAL EXAMINED: Pond A: 3 larvae.

Einfel� Kieffer

Kieffer. 1924. AnnIs. Soc. Scient. Brux. 43:393

LARVA: Antennae five segmented. Mentum with a single

median, trifid or simple tooth and six pairs of lateral

teeth. Ventromental plates two times as long as wide. SI

plumose, SII simple. Premandibles bifid. Pecten

epipharyngis a simple bar with fowr to eight, or 16 to 20

teeth. Mandibles usually with three inner teeth, inner

margin with spines. Dorsal tooth and pecten madibularis

present. Lateral tubules absent, ventral tubules absent or

only one pair present.

PUPA: Cephalic tubercles acute, frontal seta apical or

subapical. Thoracic horns plumose. Hook row on tergite II

complete. Anterior, medial and posterior bands of shagreen

present on tergites. Segment VIII without a spur but may···

have a pad of spines.

�--

,87

REMARKS: Larvae inhabit littoral, eutrophic sediments of

shallow lentic and slow areas of lotic �aters (Pinder and

Reiss 1983). The genus is absent from fast flowing waters.

The immatures are tolerant of low oxygen levels (Wilson and

McGill 1982).

There are 16 species known th�oughout the temperate

regions of the Holarctic (Pinder and Reiss 1983). In the

Nearctic there are seven species (Oliver 1981) widespread

south of the treeline (Oliver and Roussel 1983).

One species was collected in this study.

�infeldi� sp�

(Figures 90 to 96)

LARVA: n = 2

Antenna: First segment 87.4-97.4 um long, antennal ratio

1.54-1.59. Third and fourth segments subequal. Ring organ

27.5-30.4.um from base of first segment. Antennal blade

reaches to apex of fourth segment or beyond. Lauterborn's

organs sessile on apex of segment two.

Labrum: Pecten epipharyngis with sixteen teeth. Frontal

apotome with a shallow circular depression. SI plumose.

Mentum: Median tooth crenulate, first and second laterals

partially fused, remaining lateral teeth decreasing in size.

Ventromental plate 165.0-189.8 urn long, 52.5-55.7 urn wide;

anterior margin smooth, striations prominent reaching

two-thirds up the plates.

Mandible: Length 190.0-220.4 u�. Pale dorsal tooth, apical

r

88

·tooth and three inner teeth dark. Seta subdentalis simple

an� short. Pecten mandibularis well developed, in a slight

arc. Each seta interna with four major branches, repeatedly

subdivided.

Body: Anterior parapods separate, each with a crown of

claws. Procerci short, with eigh� anal setae. Posterior

parapods with apical crown of simple claws.

PUPA: n = 2

Color: Light brown to transparent.

Length: Total length 9.2-9.6 mm; abdominal length 7.1-7.7

mm.

Cephalothorax: Cephalic tubercles acute, length 73.5 (n=1),

apex cupped with a short frontal seta. Dorsal surface

nodulate.

Abdomen: Segment II with Pedes spurii B present. Hook row

on tergite II complete, three-quarters width of segment.

Shagreen on tergite II sparse. Tergites III, IV, V, and VI

with shagreen increasing in size posteriorly; to medial,

posterior patches of very strong spinules with a short seta

in the center of each patch. Tergite VII with an anterior

medial area of sparse shagreen. Tergite VIII with two

diffuse, sparse medial patches of shagreen. Lateral setae on

segments V, VI, VII, VIII are 4, 4, 4, 5 respectively. Spur

on segment VIII a small pale double spine or banched spine.

Anal lobes with 60 or more hairs on each lobes.

BIOLOGICAL NOTES: The larval specimens were collected in

89

late July and late August.

REMARKS: The larvae key to Ei�feldl� species group A in

Pinder and Reiss (1983) which includes ��� Meigen,

£ecto�li� Kieffer and �ch� Oliver. The larvae do not

completely fit the description for g. �� giv"en by Curry

(1961). Gillespie (1974) states �hat identification of

females is difficult without associated male material.

Reared males will be needed to definitely confirm the species

identification.

MATERIAL EXAMINED: Pond A: reared female and a pupa with

associated larval exuvium.

En£2.£blronomus Kieffer

'Kieffer. 1918. Budapest Magyar Nemzeti Muz., Ana. Hist. Nat.

16:69

LARVA: Antennae five segmented. Mentum with three or four

elevated medial teeth and six pairs of lateral teeth.

Ventromental plates relatively narrow, with central and

anterior bands of striations. SI long and slender with inner

margin plumose or pectinate; SII plumose. Pecten

epipharyngis made of three teeth bearing scales.

Premandibles with two or three apical teeth. Mandibles with

three or four inner teeth, seta subdentalis simple, pecten

mandibular is present. Ventral tubules absent.

PUPA: Cephalic tubercles low, frontal setae absent.

Thoracic horns plumose. Pedes spurii 8 present on segment

---

,

90

II. Hook row on tergite II complete. Tergites II to VI with

and anterior and posterior row of coarse spinules. Lateral

setae on segments V to VII variable, on segment VIII there

are five. Spur on segment VIII a comb of weak spines. Hair

fringe on the anal lobes has a medial tuft of dark filaments.

REMARKS: Only two species are reqognized at present from the

Nearctic; �. nigrica.!2§. and �. subtendens (Simpson and Bode

1980). Although Simpson and Bode separate the two species in

the larval stage, Mason (1983) found his larval material

variable between the' two species. He suggests that the two

species may be a single highly variable species (Mason 1983).

The larvae prefer lentic or slow moving lotic conditions

(Oliver and Roussel 1983) where they inhabit the detrital

sediments of the littoral zone or mine into dead macrophytes

(Pinder and Reiss 1983).

The genus is represented in the Holarctic by fifteen

species widespread in the' temperate zones (Pinder and Reiss

1983). The two species found in the Nearctjc are found south

of the treeline (Oliver and Roussel 1983).

One species was collected in this study.

Endochironomus nigricans (Johannsen)

(Figures 97 to 104)

Johannsen. 1905. Bull. N.Y. State. Mus. 86:219

LARVA: n = 2

Antenna: First segment 111.3-116.3 um long, antennal ratio

1.5-1.8, third segment longer than fourth segment. Ring

91

organ 21.3 um from base of first segment. Antennal blade

reaches to apex of fourth segment. Lauterborn's organs

vestigial.

Labrum: SI broad serrate (Mason 1983). Pecten epipharyngis

made of three small scales, each toothed on the edge as well

as on the dorsal surface. Premanqibles unevenly bifid.

Mentum: Sixteen dark teeth; second laterals shorter than

third. Ventromental plate 184.7-195.0 um long and 38.0-45.0

um wide; prominently striated medially, much more distinct

than anterior striations; anterior margin very minutely

crenulated.

Mandible: Length 230.2-272.0 um •. Dorsal tooth present;

apical tooth and three inner teeth dark. Pecten mandibularis

well developed in a shallow arc. Seta subdentalis simple,

24.0-32.5 um long. Seta interna with three major branches.

Body: Anterior parapods separate, each with a crown of fine

claws. Procerci small, bearing 10 anal setae. Posterior

parapods each with a crown of simple �laws.

PUPA: n = 10

Color: Dark brown.

Length: Total length, 9.3 (8.6-10.3) mm; abdominal length

7.2 (7.0-8.0) mm.

Cephalothorax: Cephalic tubercles low, with a apical frontal

seta. Dorsal surface of thorax smooth.

Abdomen: Tergite I bare. Tergite II with a complete hook

row made of about 37 dark hooks, about two-thirds the width

92

of the segment. Tergites II to V with strong anterior and

posterior bands of dark shagreen, interrupted medially.

Tergite VI with an anterior band of shagreen, but posterior

band diffuse. Tergites VII and VIII with sparse shagreen.

Conjunctives with spinules. Lateral setae V-3, VI-3, VII-4,

VIII-5. Spur of segment VIII with 5 to 8 spines on a short,

pale paw-like structure. Anal lobe with 60 or more hairs per

lobe, medial region of hair fringe with a distinct tuft of

longer, darker hairs.

BIOLOGICAL NOTES: Larvae of this species are found in small

lentic or slow moving lotic habitats with high concentrations

of organic nutrients and abundant aquatic macrophytes (Mason

1983; Simpson and Bode 1980; Beck 1977; Gillespie 1974; Paine

and Gaufin 1956; Johnannsen 1937b). The larvae mine into

leaves or stems of plants, or use them as a substrate for a

silken net to filter feed with (Berg 1950; Gillespie 1974r

Danks and Jones 1978).

REMARKS: The larval specimens keyed easily in Simpson and

Bode (1980). The characters of the specimens fit those of

Endochiro�� nigrican� except for the antennal ratio which

is intermediate between the g. nigrica� and g. �ubtend�.

The pupal exuviae examined key out easily in Roback

(1957), however he states that there is no frontal seta on

the apical tubercle, but the specimens examined have a

distinct apical frontal seta.

DISTRIBUTION: �dochi£�� ��ricans has been collected

,

j-

93

from British Columbia east to Quebec and south to California

and Florida (Gillespie 1974).

MATERIAL EXAMINED: Pond A: reared male, 13 pupal exuviae, 1

pupa with associated larval exuvium. Pond H: 2 pupal

exuviae.

Gl1EtotendiE£§ Kieffer

Kieffer. 1913. BioI. Centbl. 33:325

LARVA: Antennae five segmented. Mentum with a broad, simple

median tooth and six pairs of. lateral teeth. Ventromental

plates with anterior margin crenulate. SI plumose, SII

simple. Ptemandibles bifid. Pecten epipharyngis a bar with

up to 18 teeth. Mandibles with three inner teeth. Apical

tooth, dorsal tooth, pecten mandibularis, seta subdentalis

and seta interna present. Procerci present. One pair of

ventral tubules on abdominal segment VIII present or absent.

PUPA: Cephalic tubercles present. Thoracic horns plumose.

Hook row on tergite II complete, Pedes spurii B present.

Abdominal tergites II/III to VI with mace-like processes.

Shagreen on tergites variable. Lateral setae on segments V,

VI, VII, VlII; 4, 4, 4, 5, respecitively. Spur on segment

VIII made of a variable number of spines or absent. Hair

fringe well developed on anal lobes.

REMARKS: The genus is divided into three subgenera,

Gl1Etot�diEes (s. str.), g. (Ehytoten�iEes) and g.

(Demeijerea) (Oliver and Roussel 1983). However Pinder and

L

94

Reiss (1983) raised Demeije£� to full generic status and

suggest that neutral terms be used until the genus

Gl1ptotendi� has been revised.

Larvae inhabit all types of lentic water and the slower

regions of lotic habitats (Oliver and Roussel 1983). They

prefer detritus rich littoral sediments, periphyton and

mining into decaying macrophytes (Pinder and Reiss 1983).

The genus has been reported from the Afrotropical region,

and the Oriental region as well as the Holarctic.

Twenty-five species have been reported from the Holarctic

(Pinder and Reiss 1983) including thirteen from the Nearctic

(Oliver 1981).

Two species were collected in this study.

Key to Pupae of �ptot�D£l�

1a. Maces on tergites II to VI (Fig. 110) ••••••••••••••

•••••••••••••••••• � •••••••••�11B!�ndi� barbi�

1b. Maces on tergites III to VI (Fig. 111) •••••••••••••

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • _g.!J::.E£.g!£!2.2l�.2 s p •

�ptoten�ipes (Eh�totendiE�) ba£QiE� (Staeger)

(Figures 105 to 110)

Staeger. 1839. Naturhist. Tidsskr. 2:561

LARVA: n = 10, unless otherwise stated.

Antenna: First segment 55.5 (137.5-180.0) urn long; antennal

ratio 1.52 (1.35-1.97). Segments three and four subequal.

Ring organ 45.3 (33.0-67.5) urn from base of first segment.

95

Antennal blade 83.5· (72.5-95.0) (n=6) um long, accessory

blade �horter than haif of segment two.

Labrum: SI plumose, SII simple. Pecten epipharyngis a

single plate with over 18 irregular teeth. Premandibles

unevenly bifid, premandibular brush present.

Mentum: Middle tooth crenulate; first laterals same height

as middle tooth. Ventromental plates separated by 1 1/2

times the width of median tooth, striations distinct.

Mandible: Length 357.0 (304.0-387.0) um. Apical and first

two inner teeth dark, third inner tooth may be indistinct and

pale. Pecten mandibularis in a simple arc with 18 or more

lamalle. Seta subdentalis short and simple. Seta interna

made of four main branches each distally subdivided. Inner

and outer margins smooth.

Body: Anterior parapods separate each with a crown of claws.

Eighth abdominal segment with one pair of ventral tubules.

Procerci short bearing 7 anal setae. Posterior parapods with

a crown of simple claws.

PUPA: n = 10

Color: Dark brown or black.

Length: Total length, 11.3 (10.3-12.3) mm; abdominal length

8.8 (7.9-9.8) mm.

Cephalothorax: Cephalic tubercles large and acute, apical

seta about three-quarters the length of the tubercle. Dorsal

surface with small nodulations.

Abdomen: All tergites have a dark background pigmentation.

96

Hook row on tergite II about 7/8's the width of the segment.

Shagreen relatively uniform, increasing in strength slightly

posteriorly on each segment. Tergites II to VI bearing a

mace-like process which increases in size caudally; maces are

dark, bearing a number of posteriorly directed spines; area

immediately around the maces is b�re. Segments V, VI, VII,

VIII, with 4, 4, 4, 5, lateral setae respectively. Spur on

segment VIII absent or with only a slight indication of

spines. Anal lobes with hair fringe of 60 or more hairs on

each lobe.

BIOLOGICAL NOTES: The digestive tracts of the larvae

contained detritus and diatoms. Gl�endi� barbipes

emerged throughout the year in pond A, but had a peak

emergence from late May to June.

REMARKS: The larva key to Gl1£totendip� species group A in

Pinder and Reiss (1983) and to Gl1£1£tendipes (Ph�tendi�)in Oliver and Roussel (1983). Reared adult males key to Q.

barbipes in Townes (1945).

DISTRIBUTION: Gl1ptotendiE� £�bi� is a Holarctic

species. In North America it has been reported from British

Columbia east to New York and south to Illinois and New

Je'rsey (Gillespie' 1974).'

MATERIAL EXAMINED: Pond A: 5 reared males; 5 reared

females; 8 pupae with associated larval exuviae; 35 pupal

exuvaie and 23 larvae.

Q11ptotendi� sp.

97

(Figure 111)

LARVA: No larvae collected of this species.

PUPA: n = 1

Color: Dark brown

Length: Total length 6.9 mm; abdominal length 5.2 mm.

Cephalothorax: Cephalic tubercles obscured. Dorsal surface

smooth, but wrinkled.

Abdomen: Hook row on tergite II 7/8's width of segment,

hooks very fine. Pedes spurii B present on segment II.

Tergites II to VI with an anterior band of dark shagreen;

shagreen uniform over remainder of each segment. Tergite VII

with two anterior patches of sparse shagreen separated

medially. Tergite VIII with shagreen uniform and a medial

bare area. Tergites III to VI with mace processes. The size

of the maces increases slightly caudally, spines on maces

produced posteriorly as well as dorsally. Segments V, VI,

VII, VIII have 4, 4, 4, 4 lateral setae respectively. Spur

on segment VIII produced more laterally, made up of four

spines. Anal lobes with a hair fringe �( 80 or more hairs on

each lobe.

BIOLOGICAL NOTES: The single pupal exuvium was collected on

July 24, 1983.

REMARKS: The specimen is in poor condition. It keys in

Roback (1957) and Johannsen (1937b) to Glyptotendipes

�ilis. Reared material will be needed to confirm the

species identification.

�-98

MATERIAL EXAMINED: Pond A: pupal exuvium.

Pa�chi£.E�..2 Lenz

Lenz. 1921. Dt. ent 2:13

LARVA: Antennae five segmented. Mentum with 13 to 15 teeth.

Ventromental plates wi th distinct ,striations, about twice as

long as wide, anterior margin crenulate. Mandibles with two

inner teeth, seta subdentalis short, seta interna present or

absent. Dorsal tooth and pecten mandibularis absent. SI and

SII simple. Premandibles bifid. Pecten epipharyngis with

three or more teeth. Procerci present. Ventral tubules

absent.

PUPA: Cephalic tubercles short, with an apical seta.

Thoracic horn plumose. Hook row on tergite II complete.

Tergites III to VI with shagreen increasing in strength

posteriorly, and caudally. Shagreen most pronounced on

tergi te VI.

REMARKS: Larvae inhabit all types of water. Some are

ectoparasitic o� other invertebrates, others mine into

submerged macrophytes (Pinder and Reiss 1983) •.

The genus is distributed world wide, with over 30 species

in the Holarctic (Pinder and Reiss 1983). Sixteen of these

are found in the Nearctic (Oliver 1981).

Three species were collected in this study, the larva·

collected may be the larva of one of the pupal stages

collected.

99

Key to Pupae of Parachiro��

1a. Length less than 6.5 mm. Spur on segment VIII

absent (Fig. 112) •••••••••••••��hironom� sp. 1

1b. Length greater than 7 mm. Spur present on segment

VIII (Fig. 113) •••••••••••••••��hir.E�� sp , 2

��chironomus sp. 1

(Figure 112)

LARVA: None associated.

PUPA: n = 5.

Color: Yellowish brown to almost transparent.

Length: Total length 6.1 (5.4-6.4) mm; abdominal length 4.6

(4.1-4.9) mm.

Cepalothorax: Cephalic tubercles acute, frontal seta on apex

of tubercle, about half the length of the tubercle. Dorsal

surface nodulated.

Abdomen: Hook row on tergite lIon a posterior extension,

two-thirds the width of the tergite. Pedes spurii B present

on segment II. Shagreen on segments III to VIII sparse,

increasing in prominence posteriorly on each segment;

posteriorly shagreen forms two patches separated by a medial

bare area. Conjunctives bare. Lateral setae; V-4, VI-4,

VII-4, VIII-S. Spur absent on VIII. Anal lobe with hair

fringe of more than 110 hairs on each lobe.

BIOLOGICAL NOTES: The pupal exuviae were collected from pond

A during July and August 1983.

100

REMARKS: This species differs from Pa�hironomus �E. 2 in

bein� smaller, lighter, having sparse shagreen, no spur on

segment VIII and having more hairs on the anal lobes.

Specimens key in Mason (1983) to Parachir�� �bortiv�.

Reared male material will be needed to verify this species

identification.

MATERIAL EXAMINED: Pond A: 8 pupal exuviae.

Parachiro�� sp. 2

(Figure 113)

LARVA: No larva were collected.

PUPA: n = 10

Color: Light brown.

Length: Total l�ngth, 7.4 (7.1-7.9) mm; abdominal length 5.8

(5.4-6.5) mm.

Cephalothorax: Cephalic tubercles acute, bearing an apical

frontal seta. Frontal seta three-quarters as long as

cephalic tubercles. Dorsal surface with nodules.

Abdomen: Hook row nn tergite II, 3/4 width of segment,

slightly elevated from the rest of the segment. Tergites II

to VI with shagreen, spinules becoming larger posteriorly in

each segment.

of spinules.

Tergite VII with only a sparse anterior band

Tergite VIII with two longitudinal areas of

shagreen. All segments with an anterior band and two

posterior patches of light brown pigmentation. Lateral setae

on segments V, VI, VII, and VIII are, 4, '4, 4, 5

respectively. Spur on segment VIII consists of one to five

101

pale brown teeth. Hair fringe of anal lobe with 75 or more

hairs on each lobe.

BIOLOGICAL NOTES: Pupal exuviae were collected from pond B

during mid-June 1983.

REMARKS: These specimens key in Mason (1983) to

£arachironomus fregue�. Reared material will be needed

verify this identification.

MATERIAL EXAMINIED: Pond A: 3 pupal exuviae. Pond B: 21'

pupal exuviae.

Parachironomus SPa 3

(Figures 114 to 117)

LARVA: n = 1

Antenna: First segment 87.0 urn long, antennal ratio 1.74,

third segment half as long as fourth. Antennal blade reaches

to midpoint of segment four. Ring organ just slightly less

than half way up the length of first segment. Lauterborn's

organs not visible.

Labrum: Pecten epipharyngis pale with about 14 teeth of

varible size. Premandibles bifid and large.

Mentum: Unicolorous, convex plate of 15 teeth. Median tooth

simple. Ventromental plates robust, anterior surface smooth,

striations sparse.

Mandible: 174.6 urn long. Two large and sharp inner teeth

present. Apical tooth slender, brown in color. Seta

subdentalis small.

Body: Anterior parapods separate. Procerci small bearing 6

,,-

102

(?) anal setae. Posterior parapods with crown of simple

claws.

PUPA: None were associated.

BIOLOGICAL NOTES: The single larval specimen was collected

on July 27, 1983 from pond A.

REMARKS: The specimen keys to Parachiron�� aborti�� in

Simpson and Bode (1980); P. �.£.!::@tus group in Pinder and

Reiss (1983); and to E. m�chr��� in Beck and Beck 1969.

It fits the description of £. �bortl�� in Mason (1983) but

is smaller in all dimehsions, suggesting that it is a third

instar.

Associated material will be required to determine the

identity of this specimen.

MATERIAL EXAMINED: Pond A: larva.

Phaen�esect� Kieffer

Kieffer. 1921. Soc. Scienf. Brux. 40:274.

LARVA: Antennae five segmented. Mentum with four median

teeth, most median pair shorter than lateral median teeth,

seven pairs of lateral teeth. Ventromental plates with

medial corners directed anteriorly; striations present in two

bands. SI broad, plumose on both sides, SII plumose. Pecten

epipharyngis three toothed scales. Premandibles bifid.

Mandibles with three inner teeth, dorsal tooth small. Pecten

mandibularis, seta subdentalis and seta interna present.

Anterior and posterior parapods each with a crown of claws.

103

Abdominal segments with lateral and ventral tubules absent.

PUPA: Cephalic tubercles wartlike with spines and preapical

frontal seta. Thoracic horns wide lumened tubules. Pedes

spurii present on segment II. Hook row on tergite II

uninterrupted. Shagreen on segments III to VI fenestrated.

Conjunctives III/IV and IV/V with ,spinules. Lateral setae on

segments V-3, VI-3, VII-4,VIII-4. Spur on segment VIII

comblike with one major tooth and several smaller ones. Anal

lobes with well developed hair fringe.

REMARKS: The genus is in a state of confusion. Pinder and

Reiss (1983) suggest that there is only one subgenus, E. (s.

str.) and that Tribel.£2 is a separate genus. Oliver and

Roussel (1983) refers to Tribelos as a subgenus of

��£2sect�; but they do acknowledge the fact that Saether

(1977) made Tribelos a genus. Pinder and Reiss (1983)

suggest that the limits of Phae�£2��!� be broadened due to

recent discoveries. It should also be noted that the genus

2�entia is not a synonym of Phaen£2�£1£� (Oliver and

Roussel 1983).

Larvae inhabit the sandy and muddy substrates of small

lentic waters and flowing waters. They also occur in the

Aufwuchs (Pinder and Reiss 1983)�

Phaenopse� is restricted to the Holarctic. Twelve

species are known, three from the Palearctic and nine from

the Nearctic (Pinder and Reiss 1983). In the Nearctic the

genus is widespread and does occur north of the treeline

,

104

(Oliver and Roussel 1983)

One species was collected in this study.

��nopsectra sp.

(Figure 118 to 121)

LARVA: n = 1

Antenna: First segment 75.0 um lqng, terminal segments 52.5

um long, antennal ratio 1.43. Ring organ 20.0 um from base

of first segment. Antennal blade 46.3 um long reaching the

apex of the fourth segment. Lauterborn's organs vestigial.

Labrum: Pecten epipharyngis a single plate with 11 teeth.

Mentum: Sixteen teeth, all about the same size.

Ventromental plates 130.0 um long, 55.0 um wide; posterior

and anterior bands of striations; medial extension of plates

reach anteriorly almost separating the four medial teeth of

the mentum; anterior margin of plates is smooth.

Mandible: Length 162.5 um. Pecten mandibularis very short,'

with about five lamallae. Seta subdentalis does not reach

third inner tooth. Seta interna with three major branches,

each of which is distally subdivided. Inner margin with two

or three small spines.

Body: Procerci short, with 7 anal setae.

PUPA: No pupae were collected.

BIOLOGICAL NOTES: The gut of the larva contained detritus.

The single specimen was collected from pond F on July 25,'

1983.

REMARKS: The sp�cimen is in poor condition. Reared material

105

will be required for species identification.

MATERIAL EXAMINED: Pond F: 1 larva.

Cladotany!arsus Kieffer

Kieffer. 1922. AnnIs. Soc. scient. Brux. 42:100

LARVA: Antennae five segmented, qn short tubercles.

Lauterborn's organs on short petioles, shorter than segment

three. Median tooth of mentum simple or trifid, flanked by

five pairs of lateral teeth. Ventromental plates closely

appressed together medially. SI comblike, bases fused; SII

plumose distally. Pecten epipharyngis with three serrated

scales. Premandibles with four or five teeth, brush well

developed. Mandibles with three inner teeth. Dorsal tooth,

seta subdentalis, seta interna and pecten mandibularis

present. Abdomen with plumose setae. Claws on posterior

parapods serrated on inner margin.

PUPA: Thoracic horns simple tubes. Tergite II with paired

point patches. Tergites II to IV with paired anterior,

longitudinal-oval spine patches. Segment VIII with spurs

consisting of 7 to 10 spines. Anal lobes with hair fringe.

REMARKS: Larvae of the genus have been found in all types of

lentic and lotic habitats (Pinder and Reiss 1983).

The genus .has a world wide distribution with 16 species

reported·from the Holarctic (Pinder and Reiss 1983). Oliver

(1981) reports that there is one widespread species in the

Nearctic, south of the treeline (Oliver and Roussel 1983).

,

106

However, Steiner ��. (1982) says there are over 10 species

and provides a key to five unnamed species.

One species was collected in this study.

Cladotanytar� sp

(Figures 122 to 127)

LARVA: n = 1

Antenna: Tubercle length 72 urn, spur absent. First segment

107 urn long; antennal ratio 1.78; second segment is

trapezoidal. Ring organ is less than 10 urn from base of

first segment. A sensory hair 36 urn long is located 61 urn

from the base of the first antenna I segment. Antennal blade

is subeq�al to the second segment •.Petiole of Lauterborn's

organs very short, not reaching the apex of the third

segment.

Labrum: Pecten epipharyngis made of three scales distally

palmate into six, four and six subdivisions. Premandible

with four teeth and a premadibular brush.

Mentum: Median tooth appears trifid because the first

laterals are appressed to it, the second laterals are longer

than the first or third laterals. Ventromental plates 98 urn

long and 18 urn wide; separated by 2 urn; lateral portion of

plates distinctly curved posteriorly.

Mandible: Length 105 urn. Apical tooth sub equal to inner

teeth. Pecten mandibularis with about ten lamallae. Seta

interna well developed.

Body: Length 5.08 mm. Anterior parapods separate, each with

107

an apical crown of fine claws. Procerci short with seven

anal s e tae , Poster ior ·parapods wi th a number of small claws,

some bearing small serrations on inner margin.

PUPA: No pupa were collected.

BIOLOGICAL NOTES: Gut of the larva contained diatoms,

detritus and filamentous algae. The specimen was collected

on July 15, 1982.

REMARKS: The larva keys to Cladot���tarsu� mancus group in

Pinder and Reiss (1983). In Steiner et al (1982) it keys to

f. sp. 2 which is near mancus group. Reared material will be

needed for species identification.

MATERIAL EXAMINED: Pond A: 1 larva.

�atan�ta� Bause

Bause. 1914. Arch. Hydrobiol. Supple 2:120

LARVA: Antennae five segmented, situated on the apex of

antennal tubercles. Spur on tubercles present or absent.

Lauterborn's organs small, if petioles are present they are

very short. Mentum with one simple or trifid median tooth

and five pairs of laterals. Ventromental plates long and

narrow, almost touching medially. Bases of SI close

together, SI comblike, SII distally plumose. Pecten

epipharyngis made of three to five lobes. Premandibles

bifid. Mandibles with two or three inner teeth. Dorsal

tooth, seta subdentalis, seta interna and pecten mandibularis

all present. Abdominal segments with plumose setae.

108

Posterior parapods with simple claws.

PUPA: Cephalic tubercles wart-like, frontal setae long.

Thorac�c horn absent or present as a tubular structure.

Pearl row on wing sheaths present. Tergite II with hook row

more than 3/4 width of segment. Tergite III with two

divergent spine patches. Tergite� IV and V with a single or

paired dark medial spine patch. Spur on segment VIII made of

four to seven small spines. Hair fringe of anal lobes

usually well developed.

REMARKS: Members of the genus inhabit a wide variety of

environmental conditions (Pinder and Reiss 1983). Many are

tolerant of low oxygen levels (Wilson and McGill 1983).

Several species are parthenogenic (Pinder and Reiss 1983).

The genus has a world wide distribution. Twenty species

are known from Europe (Pinder and Reiss 1983) and 5 are known

from the Nearctic (Oliver 1981). In Canada the genus is wide

spread, ocurring north of the treeline (Oliver and Roussel

1983).

One species was collected in this study.

�atanxtarsus sp

(Figure 128 to 132)

LARVA: n = 2, unle�s··ci�herwise stated.

Antenna: Tubercle 60.0-67.5 urn long, spur absent. First

antennal segment slightly curved, length 145.0-150.0 urn,

antennal ratio 1.9-2.0. Ring organ 10.0-15.0 urn from base of

first segment. Sensory hair 102.5-112.5 urn from base of

109

first segment. Antennal blade slightly longer than midpoint

of second segment. Lauterborn's organs small, petioles very

short.

Labrum: Pecten epipharyngis made of three scales •.

Premandible unevenly. bifid, premandibular brush well

developed.

Mentum: Eleven unicolorous teeth, median tooth simple, fifth

laterals small. Ventromental plates 130 (n=1) urn long, 30

(n=1) urn wide; striations distinct toward anterior margin;

lateral portions slightly curved posteridrly.

Mandible: Length 160.0-162.5 urn. Dorsal, apical and two

inner teeth dark. Pecten mandibularis well developed. Seta

subdentalis longer than apical tooth. Seta interna with four

main branches.

Body: Anterior parapods with a crown of claws. Abdomen with

compound setae. Procerci as long as wide, with 7 anal setae.

PUPA: No pupa were collected.

BIOLOGICAL NOTES: Digestive tract of larvae contained

diatoms and detritus. The larvae were collected in July 1982

from an algal mat in Pond A.

REMARKS: Specimens key to £. sp. 6 in Steiner � �1. (1982)

which is within the limits of £. dissimilis. Reared males

will be needed for species level identification.

MATERIAL EXAMINED: Pond A: 2 larvae.

Tanytarsus van der Wulp

110

van der Wulp. 1847. Tijdschr. v. Ent. 17:134

LARVA: Antennae five segmented, antennal tubercles long with

or without a spur. Lauterborn's organs small on petioles

longer than the combined length of the last three antennal

segments. Mentum with median tooth rounded or laterally

notched, with five pairs of laterql teeth. Ventromental

plates almost meeting medially. SI comblike, with bases

fused; SII plumose. Pecten epipharyngis made of three

serrated scales. Premandibles with three to five teeth,

premandibular brush well developed. Mandible with two or

three inner teeth. Seta subdentalis long and slender. Seta

interna and pecten mandibularus well developed. Abdominal

segments with plumose setae. Claws on posterior parapods

simple.

PUPA: Cephalic tubercles acute with a frontal setae.

Thoracic horns are single tubes. Tergites III to VI with

paired longitudinal or oval spine patches. Three, 3, 4, 4

lateral setae on segments V, VI, VII, and VIII respectively.

Spur on segment VIII comblike with eight to twelve teeth.

REMARKS: This genus is in great need of revision (Pinder and

Reiss 1983).

Larvae inhabit all types of freshwater, as well' as some

marine habitats and also some terrestrial conditions (Pinder

and Reiss 1983). Some species are intolerant to low oxygen

levels (Wilson and McGill 1982).

The genus has a world wide distribution with about 85

111

species occuring in the H�larctic region (Pinder and Reiss

1983). More than twenty species are to be found in the

Nearctic (Oliver 1981).

Three species were collected in this study, the larva may

be the larval stage of one of the pupal stages collected.

Key to Pupae of T�1!���

collected in study

1a. Cephalic tubercles conical with long frontal setae.

Tergite II with a pair of shagreen patches.

Tergite IV with parallel spine tracts (Fig. 134) •••

••••••••••••••••••••••••••••••••••• Tanytarsus sp , 1

1b. Cepalic tubercles low, rounded with short frontal

setae. Tergite II bare. Tergite IV with spine

patches slightly divergent (Fig. 135)· ••••••••••••••

•••••••••••••••••••••••••••••••••• • �nytarsus sp. 2

Tanytars�� sp , 1

(Figures 133 to 134)

LARVA: No larva have been associated.

PUPA: n = 7, unless otherwise stated.

Color: Hyaline, with black outlines.

Length: Total length 5.1 (4.2-5.8) (n=6) mm; abdominal

length 3.9 (3.1-4.3) (n=6) mm.

Cephalothorax: Cephalic tubercles long, conical with a

cupped apex and apical frontal seta which is more than twice

as long as the tubercle.

112

Abdomen: Tergite I with very sparse shagreen. Tergite II

with �n anterior and posterior pair of shagreen patches

separated medially, dark pigmentation extending from the

middle of the segment to the posterior. Pedes spurii B

present. Hook row on tergite II complete one-third width of

segment, on a posterior extension ,of the segment. Spine

patches of tergite IV longer than on V. Tergites VII and

VIII bare. Lateral setae on segments VII and VIII, 4 and 5

respectively. Spur of segment VIII dark brown, with 5 to 8

major teeth and ten or more small teeth. Anal lobe with two

dorsal hairs and a hair fringe of 40 or more hairs.

BIOLOGICAL NOTES: Pupae were collected in mid July. Pupal

exuviae were collected in mid August.

REMARKS: Adult males key to Calopsect£� neofla�ell� in

Johanssen and Townes (1952); and to l�ytar� �ofl�vell�

in Malloch (1915). The pupal specimens key in Roback (1957)

to £. �flavella but differ in the lengths of the spine

patches on tergites IV and V; the presence of hairs on the

basal region of the thoracic horns and the number of spines

on the spur on segment VIII. More material is needed to

determine the species identification.

MATERIAL EXAMINED: Pond A: 2 reared males; 5 pupal exuviae.

�nytarsus sp. 2

(Figure 135)

LARVA: No larva were collected.

PUPA: n = 1

113

Color: Transparent, hyaline.

Length: Approximately 3.5 mm total length.

Cephalothorax: Cephalic tubercles low and rounded with a

short frontal seta.

Abdomen: Tergite II bare, with a complete hook row almost as

wide as the segment. Tergite III with two longitudinal

tracts of very long spines, tracts diverge slightly. Tergite

IV with two slightly divergent longitudinal tracts of very

long spines with some short spines. Tergites V and VI with a

pair of subequal, parallel, longitudinal tracts of short

spines. Tergites VII and VIII bare. Segment VIII with a

spur of five large teeth and about 15 smaller teeth. Anal

lobe with two dorsal seta and 30 or more hairs.

BIOLOGICAL NOTES: The single pupal specimen was collected on

July 19, 1982 from pond A.

REMARKS: The specimen keys to couplet 10 in Roback (1957)

but does not agree with the descriptions of either choice in

the couplet, it appears to be closer to Cal£E�ct� nr

longiradius sp 1. More and better material is needed for a

positive identification.

MATERIAL EXAMINED: Pond A: 1 pupa.

�ytarsu� sp. 3

(Figure 136 to 140)

LARVA: n = 10

Antenna: Tubercle without a spur. First antennal segment

197.3 (167.5-247.5) urn long,· antennal ratio 2.22 (1.53-2.42).

114

Ratio of the length of the second segment to the third is

1.86 (1.16-3.60). Ring organ at the base of the first

antennal segment. Sensory hair is in the distal half of the

first segment. Antennal blade reaches midpiont of second

segment. Lauterborn's organs small on a long petiole, ratio

of petiole length to length of la�t three segments is 2.40

(1.57-3.89).

Labrum: Bases of SI close together, SI and SII·comb like.

Pe�ten epipharyngis made of three palmate scales.

Premandible with 4 teeth� the most proximal the smallest.

Premandibular brush well developed.

Mentum: Eleven teeth, median tooth pale with lateral

notches, may appear trifid. Ventromental plates close

together medially, striations distinct. Lateral end of

ventromental plates are slightly curved posteriorly.

Mandible: Length 142.8 (125.0-162.5) urn. One dorsal tooth,

apical and three inner teeth dark. Pecten mandibularis and

seta interna well developed. Seta subdentalis longer than

apex of mandible.

Body: Anterior parapods separate, each with a crown of

claws. Branched setae on abdominal segments present on

segments I to V? Procerci small with 7 anal setae.

Posterior parapods with simple claws.

BIOLOGICAL NOTES: Digestive tract contains diatoms and

detritus. The specimens were collected from Cladophora mats

during July 1982 in pond A.

115

REMARKS: Steiner�! ale (1982) keys out 7 unnamed species.

Specimens key to �lopsectra group sp. 5 in Roback (1957).

These specimens could be the larva of I. neofl��la as

Roback (1957) does not key larva of this species. To confirm

the identification reared adult male material will be

required.

MATERIAL EXAMINED: Pond A: 19 larvae.

116

Orthocladiinae

LARVA: Range in size from very small to large. Color may be

white, green, brown, blue or red.

Antennae: Four to seven segmented, varying in length from

shorter than the mandibles to longer than the head capsule.

A ring organ and/or sensory pits �re usually present on the

first segment. The antennal blade, on .the apex of the first

� segment, may be longer or shorter than the terminal segments.

Lauterborn's organs are situated on the apex of the second

segment; they may be distinct or vestigial.

Labrum: Labral seta SI'may be simple, bifid, palmate or

pectinate; SII is usually simple. Pecten epipharyngis

usually consists of three scales. Premandibles have one to

five teeth, premandibular brush may be present or absent.

Prementohypopharyngeal complex: Ligula small. Paraligula

usually an apically serrated series of scales. M-appendage

may be well developed to indistinct. Pecten hypopharyngis

consists of several transverse rows of apically serrate

scales or spines.

Mentum: Convex, usually with eight to twelve teeth.

Ventromental plates may be indistinct to well developed,

often with a setal beard, but never with striations.

Mandibles: Have a single apical tooth and two to six inner

teeth. The pecten mandibularis is absent. Seta interna

usually well developed with four to eight plumose or

subdivided branch�s. Seta sub dental is usually present. The

117

outer surface of the mandibles are usually smooth but may be

crenulate.

Maxillary palps: Always shorter than wide.

Body: Anterior para pods usually separate, with an apical

crown of claws. Abdominal setae usually simple, sometimes

plumose. Procerci usually presen� with two lateral setae and

three to seven anal setae, often with dorsal spurs.

Posterior parapods usually separated, well developed with

apical crown of claws. Two pairs of anal. tubules usually

present.

PUPA: Range in size from 2 to 12 mm in length. Color ranges

from dark to pale.

Cephalothorax: Cephalic tubercles and frontal setae present

or absent. Thoracic horns present or absent, when present

they may be simple tubes of various shapes, with or without

spines on the surface.

Abdomen: Tergites have a variety of armatures, from uniform

shagreen, to distinct patterns of shagreen, spines and hooks.

Anal lobes usually have three, macrosetae and/or a variably

developed hair fringe may be present or absent.

KEY TO ORTHOCLADIINAE GENERA

collected in study

LARVAE

1a. Antennae longer than head capsule, four segmented

(Fig. 149) •••••••••••••••••••••••••••• Corl.!lS!�ur�

1b. Antennae as long as mandibles, usually five

118

segmented ••••••••••••••••••••••••••••••••••••••••• 2

2a. 51 and 511 bifid ••••••••••••••••••••••Eseudosmittia

Zb , SIr simple ....•••••••••••.••..•.••••.••••••...•... 3

3a. Premandibles with two apical teeth (Fig. 156) ••••• 4

3b. Premandibles with one apical tooth (Fig. 143) ••••• 6

4a. Antennae six segmented. 51 plumose (Fig. 167) •••••

•• •• ••• • •• • ••••• •••• •• •• •• •• •••• •• •• •• • • !:!ydrobae�

4b. Antennae five segmented. 51 bifid (Fig. 154) or

plumose ••••••••••••••• � ••••••••••••••••••••••••••• 5

5a. SI bifid (Fig. 154). Pecten epipharyngis a broad

conical plate of fused scales (Fig. 155) •••••••••••

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • ., • • • • • • • C ric 0 t .Q£.!:!.2

5b. SI plumose. Pecten epipharyngis three subequal

scales ••••••••••••••••••••••••••••••••••• Limnophyes---

6a. Ventromental plates with a beard (Fig. 144). 51

bifid (Fig. 142) •••••• � •••••••••••••••••�cricoto£�

6b. Ventromental plates with a sparse beard (Fig 176,

185). SI palmate (Fig. 174, 183) •••• Psec1!££1adius

PUPAE

1a. Anal lobes bare (Fig. ·191) ••••••••••••Eseudosmitti�

1 b. Anal lobes with short hair fringe and/or three or

macrosetae (Fig 190) •••••••••••••••••••••••••••••• 2

2a. Anal lobes with hair fringe (Fig. 181) •••••••••••• 3

2b. Anal lobes with hair fringe absent (Fig. 165) ••••• 5

3a. Hair fringe on anal lobes sparse (Fig. 1 71 ) ••••••••

•••••••••••••••••••••••••••••••••••••••• !:!ydrobaenus

,

119

3b. Hair fringe more extensive (Fig. 148, 181) •••••••• 4

4a. Thoracic horn absent ••••••••••••••••••••�£����

4b. Thoracic horn club shaped (Fig. 179) •••••••••••••••

••••• ••• •• ••••• • • ••• •• • • • • •••••• •• •• • �tr.2.£ladiu§

Sa. Tergites II - VIII.with posterior row of long pale

spines (Fig. 172). Anal macrasetae long and curved

( Fig • 1 7 2 ) • • • • • • • • • • • • • • • • • • • • • • .• • • • • • .'. .1..i.m.!22.El:!�

5b. Tergites without posterior row of long spines ••••• 6

6a. Shagreen uniform (Fig. 161) or banded (Fig. 163) on

tergites III and IV. Segments VII to VIII pale ••••

• • • • • • • • • .'. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • C ric a t DE u s----

6b. Shagreen sparse. Tergites with paired medial spine

patches (Fig. 147) •••••••••••••••••••••• ..acric£!�E,!;!.§

Acricoto�§ Kieffer

Kieffer. 1921. Bull. Soc. His. Nat. Metz. 29:90

LARVA: Medium sized. Antennae five segmented. Mentum with

one median tooth and six pairs of lateral teeth.

Ventromental plates well developed, with a beard. SI bifid.

Pecten epipharyngis three simple scales. Premandibles

unevenly bifid. Mandibles with three inner teeth, apical

tooth slightly longer than width of inner teeth. Seta

subdentalis present, seta interna absent. Anterior parapods

separate; each with apical group of claws. Abdominal

segments have long, simple setae. Two pairs of anal tubules;

shorter than posterior parapods. Procerci strongly

120

sclerotized with slight indication of spurs; six anal setae

present.

PUPA: Cephalic tubercles low, frontal setae present.

Thoracic horns with spines. Pedes spurii present on segment

II. Hook row on tergite II made of dark hooks. Tergites II

to VI with paired central spine patches. Segments VII and

VIII with four or five lateral setae. Anal lobes without

hair fringe but with three anal macrosetae.

REMARKS: The immatures are found in all types of fresh

water, but prefer small shallow bodies of water. They are

tolerant of low oxygen levels (Wilson and McGill 1982).

Five species are known from the Holarctic (Cranston, et

�1. 1983). Only two are known from the Nearctic (Oliver

1981 ).

Only one species was collected in this study.

�£flEot££� senex (Johannsen)

(Figures 141 to 147)

Johannsen. 1937. Mem. Cornell. Univ. Agric. Exp. Stat. 205:63

LARVAE: n = 10

Antenna: First segment 88.1 (73.4-103.7) um long. Antennal

ratio 2.27 (2.07-2.43). Each segment consecutively smaller.

Laut e r bo rn r s organs" abollt "three quarters as long as third

antennal segment. Blade shorter than combined length of

terminal segments.

Labrum: SI unevenly bifid, larger branch feathered at the

tip making it appear plumose. Pecten epipharyngis consists

•

121

of three "subequal pointed scales. Premandibles with a single

apical tooth.

Mentum: Median tooth sometimes weakly divided into four

parts. Six pairs of lateral teeth consecutively smaller.

Ventromental plates with a well developed setal beard.

Mandible: Length 217.7 (192.3 - �42.9) um. Surface of

mandible smooth or very weakly crenulated.

Occipital margin: Very dark, with two dark projections.

Body: Procerci strongly sclerotized with slight indication

of spurs.

PUPAE: n = 10

Color: Dark brown.

Length Total length 5.6 (5.1-6.0) mm; abdominal length 4.1

(3.6-4.6) mm.

Cephalothorax: Cephalic tubercles low with preapical frontal

seta, about 7 times "as long as tubercle. Thoracic horns

300.2 (251.4-350.0) um long, covered with spines. Dorsal

surfa�e covered with nodulations.

Abdomen: Hook row on tergite II a multiple__ �ow of dark

hooks. Paired patches on II to VI of short black spines and

2 posterior bands of shagreen, increasing in size and number

caudally. Tergite VI with only one posterior band of

spinules. Lateral setae; 111-3, IV-4, V-4, VI-4, VII-4,

VIII-5. One of the lateral setae on VIII larger than the

rest. Anal lobes with three sub equal macrosetae.

BIOLOGICAL NOTES: The gut contents of the larvae were

•

122

diatoms, filamentous algae, and detritus. �£!l££!£�� ��!

emerged from pond A in late April and early May in 1983.

REMARKS: The larvae can be keyed in Johannsen (1937a), but

the pupal specimens have a pair of spine patches on tergites

II to VI rather than a transverse row. Adult specimens key

in Johannsen and Townes (1952).

DISTRIBUTION: Acricoto� ��! has been previously recorded

from lA, NY and PA (Sublette and Sublette 1965).

MATERIAL EXAMINED: Pond A: 6 males, 4 pupae, 58 pupal

exuviae, 11 larvae, and 4 larval exuviae. Pond B: 3 larvae.

Pond F: 14 larvae.

Cor���� Winnertz

Winnertz. 1846. Stettin. ent. Ztg. 7:12

LARVA: Small, three mm or less in length. Head capsule has

sculpturing on it. Antennae four segmented, longer than head

capsule. Mentum triangular with two or three medial teeth

and five pairs of lateral teeth. Ventromental plates

reduced. SI and SII simple. Pecten epipharyngis made of

three or five scales. Premandibles serrated apically.

Mandibles with four inner teeth, apical tooth very short.

Seta interna present. Seta subdentalis absent. Mesothoracic

and metathoracic segments fused. Procerci have four anal

setae. Variably developed seta arising from ventral surface

of posterior parapods.

PUPA: Thoracic horns absent. Wing sheaths with pearl rows

�--

,

123

(Fig 6). Anal macrosetae filamentous.

REMARKS: Larvae are usually associated with submerged or

floating macrophytes in all types of freshwater habitats

(Cranston, �! �. 1983). They are tolerant to moderately low

levels of oxygen (Wilson and McGill 1982).

CO£XDoneura seems to be a large genus with a world wide

distribution (Cranston, �! ale 1983). Over twenty species

are known from the Nearctic (Oliver 1981).

Two life stages were collected in this study.

Con.QE�� (C0.EYD��) sp , 1

(Figure 148)

LARVA: No larvae were associated.

PUPAE: n = 5, unless otherwise stated.

Color: Pale brown.

Length: Total length 2.8 (2.6-2.9) (n=4) mm; abdominal

length 2.0 (1.8-2.2) mm.

Cephalothorax: Dorsal surface with fine nodulations. Wing

sheaths with double pearl row.

Abdomen: Tergite I with sparse hair like shagreen. Hook row

on tergite II absent. Tergites II to VIII with uniform

sparse shagreen and a line of short spines on the posterior

margin of each segment. Segments III to VIII with four large

lateral setae. Conjuctives bare. Anal lobes with hair

fringe consisting of 54 hairs and three lamallar hairs. One

lamallar hair on each of the genital sac apices.

BIOLOGICAL NOTES: Exuviae were collected from Pond A in late

,-

124

April.

REMARKS:' The specimens key to £2���� �le!l� in

Roback (1957) and to Cor�no�� (Cor�noneura) sp in

Johannsen (1937). Reared material will be required to

positively identify these specimens to species.

MATERIAL EXAMINED: Pond A: 5 pupal exuviae.

£££���� (Corynoneura) sp. 2

(Figures 149 to 152)

LARVA: n = 1

Head capsule: Surface slightly sculptured.

Antenna: First segment 299.0 urn long, antennal ratio 1.33.

Second and third segments subequal and dark. Sensory pit

165.0 urn from base of first segment. Blade 17.5 urn long.

Labrum: Pecten epipharyngis'with five simple scales.

Premandibles with six teeth on inner margin.

Mentum: Triangular. Five lateral teeth. Median tooth

trifid, center division one-third size of lateral divisions.

Ventromental plates appear vestigial.

Mandible: Length 77.0 urn. Apical tooth shorter than first

inner tooth. Inner margin with three inner teeth. Seta

interna present.

Body: Anterior parapods separated, each with a crown of

claws. Procerci small, spurs absent. Posterior parapods

with a 70 urn long brown spur half way down the length, spur

is bare except for basal hairs. Claws of ptisterior parapods

simple.

,-

125

PUPA: No pupa were associated with the larva collected.

BIOLOGICAL NOTES: The gut of the larva contained diatoms.

The specimen was collected on April 29.

REMARKS: The specimen keys to fB£1�� tari� in Simpson

and Bode (1980). Reared material will be required to confirm

the species identification.

MATERIAL EXAMINED: Pond A: larva.

Cricot£E� van der Wulp

van der Wulp. 1874. Tijdschr. Ent. 17:132

LARVA: Antennae five segmented. Mentum with one median

tooth, and six pairs of lateral teeth. Ventromental plates

reduced. 51 usually bifid. Pecten epipharyngis consisting

of three scales or a single scale. Premandibles with one or

two apical teeth. Mandibles with three inner teeth, outer

margin sometimes crenulate. Apical tooth shorter than

combined width of inner teeth. Seta subdentalis present,

seta interna usually present. Anterior and posterior

parapods each with a crown of claws. Seta L4 on abdominal

segments I to VI/VII often plumose. Procerci as long as

wide, spur absent, with six or seven anal setae.

PUPA: Frontal setae present. Thoracic horn a short tube.

Hook row on tergite II at least one third as wide as segment.

Tergites III to V with variable shagreen patterns. Tergites

VII and VIII bare. Anal lobes without hair fringe, with

three short terminal macrosetae.

l

126

REMARKS: Cricol£� is one of the largest genera in the

Orthocladiinae. The genus is divided into three subgenera;

Cric£iQ� (s. str.), f. (Isocladi�), f. (�tocladi�)

(Cranston, � ale 1983).

Larvae are usually associated with submerged macrophytes

and algae of most types of freshw�ter environments;

Cricol£�� (s. str.) generally inhabits lotic conditions, f.

(Isocladi�) prefers lentic habitats and f. (Nostococ�di�)inhabits Nostoc colonies (Cranston, et ale 1983; Oliver and

---- -- --

Roussel 1983).

The genus is world wide in distribution, occurring

everywhere except Antarctica. Over twenty species have been

identified from the Nearctic (Cranston, Oliver and Saether

1983) •

Three species were collected in this study.

Key to Pupae of Cricot��

collected in the study

1a. Tergites II to VI pigmented (Fig. 161). Thoracic

horns longer than 350 _l:''!1 (Fig 160) •••••••••••••••••

•••• •• •• •••• •••••••• •••••• •• ••••• Cricoto� �£��

1b. Tergites pale (Fig. 163, 165). Thoracic horns less

than 150 urn long •••••••••••••••••••••••••••••••••• 2

2a. Tergites III to V with central and posterior bands

of shagreen (Fig. 163). Thoracic horns 117 urn

long ••••••••••••••••••••••••••••••• Cricotopus sp , ·1

2b. Shagreen on tergites II to VI uniform (Fig. 165).

,-

I

127

Thoracic horns about 147 um long ••• Cricoto£� sp. 2

Cri££topus (�ocladius) ornatus (Meigen)

(Figures 153 to 161)

Meigen. 1818. Systematische Beschreibung derbekannten

europaischen zweiflugeligen Insekten. Erster Theil. Aachen:

43

LARVA: n = 10

Antenna: First antennal segment 64.4 (55.7-73.4) um long;

antennal ratio 1.8 (1.5-2.07). Each segment shorter than

preceeding one. Lauterborn's organs distinct. Both sensory

pits are located close to the ring organ in the basal portion

of the first antennal segment. Antennal blade shorter than

combined length of terminal segments.

Labrum: SI bifid. Pecten epipharyngis consists of a broad

conical plate of fused scales. Premandibles bifid.

Mentum: One median tooth and six pairs of lateral teeth.

First two laterals may be fused. Ventromental plates small

and indistinct, never with setae.

Mandible: Length 185.5 (169.5 - 212.5) um. Three inner

teeth brown. Seta Lrrt e rna di vided into a number of

filaments. Seta subdentalis short. Inner margin of mandible

smooth, outer margin crenulate.

Body: Abdominal segments I to VII with setae L4 plumose.

Seta L4 on segment VII with a least three branches.

PUPAE: n = 10, unless otherwise stated.

,-

128

Color: Dorsal surface of cephalothorax and abdominal

tergites II to VI dark brown, tergites VII and VIII pale.

Length: Total length 5.4 (4.7-5.9) mm; abdomen length 3.9

(3.5-4.4) mm.

Cephalothorax: Cephalic tubercles low knobs with very long

frontal setae. Thoracic horns 416.0 (374.7-463.4) (n=8) um

long, dark brown, with small indistinct spines. Dorsal

surface with brown nodulations.

Abdomen: Tergite I bare. Hook rowan a posterior extension

of tergite II, half as wide as segment. Pedes spurii absent.

Tergites II to VI with dark brown pigment in posterior half.

Shagreen on tergites II to VI uniform, spinules increase in

size posteriorly. Tergites VII and VIII very pale, with

sparse shagreen anteriorly, posterior bare. Conjunctives

between segments III and IV, IV and V, and V and VI with a

band of pale spinules. Anal lobes with blunt apices and

three straight sub equal anal macrosetae.

BIOLOGICAL NOTES: Cricotopus £!�� was a common species

collected from pond A. Most immatures specimens were

collected from submerged macrophytes and algae.

The digestive tract of the larvae contained mostly

diatoms with some detritus.

REMARKS: The specimens can be identified using Hirenojoa

(1973). Cricotopus ornat� belongs to the �y!vestris group_

The larva can be distinguished from other Cri�to��

(Isocladi�) specie� by the plumose L4 setae on abdominal

,-

129

segments I to VII. The pupae are darker brown than the pupae

of the other two species collected in the study.

DISTRIBUTION: Hirvenjoa (1973) reports that CricotE�

.E£!:!�.2 has a Holarctic distribubion.

SPECIMENS EXAMINED: Pond .A: reared male, 2 pupae with

associated larval exuviae, 22 pup�l exuviae, 46 larvae.

CricEtoE� (Cricoto�) SPa 1

(Figures 162 to 163)

LARVA: None were collected.

PUPA: n = 5

Color: Transparent to light brown.

Length: Total length 4.5 (4.4-4.5) mm; abdominal length 3.1

( 3 • 0 - 3 • 1) mm.

Cephalothorax: Cephalic tubercles absent. Thoracic horns

small 117.9 (93.6-128.9) um long, spines present on the

surface. Dorsal surface wrinkled, nodulations absent.

Abdomen: Tergite I with central transverse band of shagreen.

Hook row on tergite II 1/2 as wide as segment, on a posterior

extension of the segment. Pedes spurii B on segments II and

III. Te�gites III to V with a central shagreen patch and a

posterior shagreen band. Shagreen on segments VII and VIII

absent or sparse. Anal lobes with three sub equal anal

macrosetae.

BIOLOGICAL NOTES: All pupal exuviae of Cricol£� SPa 1 were

collected in late May.

REMARKS: The specimens key in to Cri£QtoE� (££i£Q!E�.2)

,-

,

130

tribial� group Hirvenjoa (1973). All specimens were in poor

condition. Better and reared material will be needed for

species identification.

MATERIAL EXAMINED: Pond A: 5 pupal exuviae.

Crl�to�� (�ocladiu�) SPa 2

( Fig u res ' 1 64.to 1 65 )

LARVA: None were collected.

PUPA: n = 1

Color: Transparent to light brown.

Length: Total length 5.3 mm; abdomen 3.9 mm.

Cephalothorax: Cephalic tubercles absent, frontal setae

extremely long. Dorsal surface weakly nodulated. Thoracic

horn 147.9 urn long spines present.

Abdomen: Tergite I with a central transverse band of

shagreen. Hook row on tergite II more than 1/2 the width of

segment. Pedes spurii B absent. Shagreen on tergites II to

VI uniform. Tergites VII and VIII with sparse shagreen.

Anal lobes with three subequal anal macrosetae.

BIOLOGICAL NOTES: The specimen was collected on Aug 9, 1983.

REMARKS: The specimen keys to Cricotoeus (l�ocl�dius)

�xlv�ri� group in Hirvenjoa (1973). Reared material will

be needed for species identification.

MATERIAL EXAMINED: Pond A: pupal exuvium.

�ydroba� Fries

Fries. 1830. K. svenska Vetensk-Akad Handl. 1829:177

J

1 31

LARVAE: Antennae six segmented, sixth segment minute, often

very diffic�lt to see. An�ennal blade shorter than combined

length of terminal segments. Lauterborn's organs distinct.

SI plumose, SII simple. Premandibles bifid. Labral lamallae

a single scale. Pecten epipharyngis three simple scales.

Mentum with 2 median teeth and si� pairs of lateral teeth.

Ventromental plates large, rounded, without a beard.

Mandibles with three or four inner teeth, apical tooth short,

seta interna and seta subdentalis present. Parapods

separate, each with a crown of claws. Procerci short, with

seven anal setae.

PUPA: Frontal setae present, cephalic tubercles usually

absent. Thoracic horns long with sparse covering of spines.

Dorsal surface of thorax and wings usually smooth. Hook row

on tergite II weak. Pedes spurii 8 present on segment II.

Lateral setae on segments V, VI, VII, VIII; 4, 4, 4, 4 or 5

respectively. Anal lobes with a variable hair fringe and

three anal macrosetae.

REMARKS: Saether (1976) recognises five species groups in

the genus.

The immatures of most species inhabit the littoral

regions of most types of freshwater, preferring northern

oligotrophic conditions (Saether 1976).

�ydro�� is a holarctic genus with 20 species known.

Thirteen species are known from the Nearctic (Saether 1976).

The genus is widespread in Canada occurring north of the

,-

132

treeline (Oliver and Roussel 1983).

Two life stages were collected in this study.

!:!ydroba� sp , 1

(Figure 171)

LARVA: None were associated.

PUPA: n = 9

Color: Grey to transparent.

Length: Total length 4.9 (4.8-5.3) mm; abdominal length 3.7

(3.6-4.0) mm.

Cephalothorax: Cephalic tubercles absent. Thoracic horns

covered in spines, length 426.7 (404.3-458.5) urn. Dorsal

surface slightly wrinkled.

Abdomen: Hook row on tergite II reduced. Tergites II to VI

with uniform shagreen, points increasing in size posteriorly.

Conjuntives bare. Shagreen on tergite VII sparse. Tergite

VIII almost bare. Anal lobes with about 25 short hairs and

three anal macrosetae.

BIOLOGICAL NOTES: The pupal exuviae were all collected in

mid May from pond D.

REMARKS: The specimens key to !:!Y2£ob�� nivori��� in

Roback (1957); and to the former's synonym Seaniotoma

(Orthocladius) n Lvo r Lundai

Ln Johannsen (1937a). In Saether

(1976) they key to couplet 7 but no further. Reared material

is needed for species identification.

MATERIAL EXAMINED: Pond D: 13 pupal exuviae.

fudrobae� sp 2

,-

I

133

(Figures 166 to 170)

LARVA: n = 9, unless otherwise stated.

Antennae: First segment 65.1 (58.2-73.4) (n=8) um long.

Antennal ratio 1.86 (1.53-2.32) (n=8). Ring organ 19.1

(15.2-22.8) (n=8) um from base of first segment.

Lauterborn's organs distinct.

Labrum: SI plumose at apex. Premandibles bifid,

premadibular brush absent.

Mentum: First lateral teeth slightly shorter and narrower

than median teeth. The median teeth and first laterals are

paler than the remaining teeth. Ventromental plates well

developed, rounded at posterior end.

Mandibles: Length 146.6 (131.6-156.9) um. Three inner teeth

and a short apical tooth. Seta subdentalis hooked apically.

Body: Procerci as long as wide with seven anal setae on

apex.

PUPA: None were associated.

BIOLOGICAL NOTES: Gut contents of larvae were detritus,

green algae and plant material. Specimens were all collected

from pond C in late April 19B4.

REMARKS: The specimens are small and in poor condition. In

Pinder and Reiss (1983) they key to Hydrobaenus ��is

group or pilipes group. In Saether (1976) they key to �.

martini but this is a very tenuous identification. Reared

material is needed for species identification.

MATERIAL EXAMINED: Pond C: 9 larvae.

a_

J

134

Limnophyes Eaton

Eaton 1875. Entomol. mon. Mag. 12:60.

LARVA: Antennae five segmented, half as long as mandible.

Mentum with two median teeth and five pairs of lateral teeth.

Ventromental plates variable, without setae. SI plumose,

rarely bifid. Pecten epipharyngis consists of three subequal

scales. Premandibles bifid or trifid without premandibular

brush. Mandibles with three inner teeth, apical tooth

shorter than the width of three inner teeth. Seta interna

and seta subdentalis present. Anterior parapods separate

'with apical crowm of claws. Abdominal setae usually simple,

sometimes plumose. Procerci with seven anal setae, spurs

absent.

PUPA: Tergites II to VIII with posterior row of long setae.

Abdominal segments III to VIII each with four lateral setae.

Anal lobes with three terminal macrosetae, hair fringe

absent.

REMARKS: .!:imnoph;tes is a species rich genus but very few of

the immatures have been identified (Oliver and Roussel 1983).

Larvae have been collected in aquatic, semi-aquatic and

terrestrial habitats (Cranston, et ale 1983). Larvae of some

species are tolerant to low oxygen levels (Wilson and McGill

1982).

Members of the genus are found world wide (Cranston, et

�. 1983). Eighteen species have been recorded from the

,-

,

135

Nearctic (Oliver 1981).

One species was collected during this study.

Limnophyes sp.

(Figure 172)

LARVA: None were collected.

PUPA: n = 5, unless otherwise st�ted.

Color: Pale.

Length: Total length 3.8 (n=1) mm; abdomen 2.5 (n=1) mm

long.

Cephalothorax: Cephalic tubercles, small knobs with frontal

setae. Thoracic horns absent.

Abdomen: Tergite I bare. Tergites II to VIII with uniform,

sparse shagreen and a posterior band of very long setae.

Lateral setae IV-4, V-4, VI-4, VII-4, VIII-5. Anal lobes

with blunt apices, and three subequal macrosetae.

BIOLOGICAL NOTES:, Oliver and Roussel (1983) reports that the

larvae commonly collected in Canada: have very short

antennae, less than half the length of the mandible; two

sensory pits present on the first antennal segment; SI

plumose; simple abdominal setae; and the apices of anal

tubules are pointed.

The exuvaie were collected from pond A in late April to

mid May.

REMARKS: The pupae of bimnophyes are very distinctive and

easily recognised by the posterior band of long setae.

Specimens were in very poor condition •. Reared material will

,

I

136

be required for species level identification.

MATERIAL EXAMINED: Pond A: 5 pupal exuviae.

Psectrocladius Kieffer

Kieffer. 1906. AnnIs. Soc., scient. Brux 30:356

LARVA: Antennae five segmented. Mentum with one or two

medial teeth and five pairs of lateral teeth. Ventromental

plates well developed, with beard present. SI palmate with

three to nine lobes. Pecten epipharyngis made up of three

subequal scales. Premandibles with one apical tooth.

Mandibles with three inner teeth, apical tooth variable in

length. Seta subdentalis present, seta interna present or

absent. Anterior and posterior parapods with a crown of

claws. Procerci large, with one or two spurs and six or

seven anal setae.

PUPA: Thoracic horns toothed, slightly swollen terminally.

Tergite II with compact pad of spines on posterior margin.

Pedes spurii B present or absent. Tergites III/IV to VI/VII

with a single or paired patch of spines or bare. Tergites V

to VIII with a posterior row of long lamallar like spines.

Anal lobes with at least three macrosetae, but may have as

many as eight, and a hair fringe.

REMARKS: Psectrocla� as been divided into four subgenera;

E. (s. str.), E. (Mon£Esectrocladius), E.

(Allopsectrocladius) and E. (Mesopsectrocladiu�) (Oliver and

Roussel 1983). The subgenera can be separated in the larval

,-

137

stage.

Larvae prefer lentic habitats (Cranston, � ale 1982).

The genus is relatively intolerant to low oxygen levels

(Wilson and McGill 1982).

The genus is distributed world wide except for Australia

and Antarctica. Sixty species fr�m all four subgenera occur

in the Holarctic (Cranston, et ale 1983). Nineteen species

are widespread in the Nearctic (Oliver 1981).

In this study three species were collected.

Key to �tr�cladi� species

collected in this study

LARVA

1a. SI palmate with 6 to 9 branches (Fig. 183).

Median teeth of mentum dome shaped (Fig. 185).

Apical tooth of mandible shorter than one and one­

half times the combined width of inner mandibular

teeth (Fig. 186) •..• e.••••••••••••••••••••••••••••••

•••••••••••••••••••••••• • Psectrocladi� (E.) sp , 1

1b. SI with 3 branches (Fig. 174). Median teeth of

mentum flat with medial nipple-like projections

(Fig. 176). Apical tooth of mandible more than one

and one-half times longer than combined width of

inner teeth (Fig. 177) ••••••••• Pseclrocladi�� (�) •

.fl!!�.

PUPA

1a. Pedes spurii B present (Fig. 190). Posterior row

,-

138

of lamallar setae on tergites II to VI (Fig.

188). Tergites IV, V and VI with paired medial

spine patches (Fig. 188, 190) ••••••••••••••••••••• 2

1b. Pedes spurii B absent (Fig. 180). Posterior row of

lamallar setae on tergites III to VIII (Fig. 180,

181). Anal lobes with anal macrosetae

absent •••••••••••••

• • • • • • • • • • • • • • • • • • • • • • • • • • • •• • ·E.2�tr.2.£ladi� (�.)flavus

2a. Anal lobes with three e�enly spaced anal macro­

setae (Fig. 188) •••••••••• Psectrocladius (E.) sp 1

2b. Anal lobes with seven anal macrosetae (Fig. 190) •

••••••••••••••••••••••••• • Psectrocladius (E.) sp 2

E��cladius (�llopse£!rocl�ius) ��� (Johannsen)

(Figures 173 to 181)

Johannsen. 1905. Bull. N. Y. state Mus. 86:270

LARVA: n = 10

Antenna: Each segment small�� than the preceding segment.

Length 245.5 (215.0-267.5) urn. Antennal ratio 3.67

(3.28-4.00). Lauterborn's organ very small and sessile.

Ring organ in basal half of first segment. Antennal blade

subequal to the second antennal segment.

Labrum: SI has three subequal branches. Premandible with a

single sickle shaped apical tooth, slightly darker than ·the

rest of premandible.

,

139

Mentum: Median teeth broad, with central nipplelike

projections. Five pairs of dark brown lateral teeth.

Ventromental plates with setae.

Mandible: Length 255.25 (240.4 - 273.6) urn. Three inner

teeth and apex of apical tooth dark brown. Ratio of apical

tooth to combined width of inner �eeth, 2.19 (1.70-2.80).

Seta interna absent. Both margins of mandibles smooth.

Occipital margin: Slightly darker than the general head

capsule color. Two projections present.

Body: Procerci approximately one and one-half times as long

as wide, slightly sclerotized, with two prominent spurs

present. Seven anal setae on each procercus.

PUPA: n = 5

Color: Dark brown.

Length: Total length 7.1 (6.0-8.2) mm; abdomen length 5.3

(4.4-6.3) mm.

Cephalothorax: Dorsal surface wrinkled, lacking nodulations.

Cephalic tubercles as low domes, frontal setae lacking.

Thoracic horns 552.6 (478.2-620.0) urn long, club shaped with

spines on the surface.

Abdomen: Tergite II with hook row on posterior extension of

segment. Pedes spurii B absent on se�m��i·II. Tergites III

to VIII with a posterior row of wide blunt simple, bifid or

trifid setae. Setal row increases in size and number of

setae caudally. Conjunctives III/IV, IV/V and V/VI with

spinules. Lateral setae V-4, VI-4, VII-4, VIII-5. Anal

I_

I

140

lobes with dense hair fringes, two dorsal setae. Inner

margins of anal lobes straight and bare, outer margin bluntly

curved.

BIOLOGICAL NOTES: Larvae were collected from submerged

macrophytes and algae in pond A. Other specimens were

collected from the culvert outflow in pond B in 1983. The

guts of the larvae contained mostly filamentous algae with

some diatoms and detritus.

The larvae, pupal exuviae and the larvae of the reared males

were collected in mid July.

REMARKS: The reared males key to Psectrocladiu� flav� in

Johanssen and Townes (1952). The larval and pupal specimens

key to .§.E�iotoma (..e��.2.£ladius) .fla� (a synonym of ..e.

flavus) in Johannsen (1937a). In Roback (1957) the immatures

agrees more closely to ..e. ���, a related species.

DISTRIBUTION: Psectrocl�dius flavus has been recorded from

New York and Saskatchewan (Mason 1983; Sublette and Sublette

1965).

MATERIAL EXAMINED: Pond A: 4 reared males, 15 larvae. Pond

B: 2 larvae.

Psect££cladiu� (E�trocladiu�) sp. 1

(Figures 182 to 188)

Larva: n = 8

Antenna: First segment 102.2 (91.1-111.32) um long; antennal

ratio 2.5 (2.0-2.9). Each segment smaller than preceding

one. Lauterborn's organs small. Ring organ located near

1-

141

base of first antennal segment. Antennal blade shorter than

combined length of terminal antennal segments.

Labrum: SI palmate with six to nine sub equal branches.

Pecten epipharyngis consists of three subequal scales.

Premandible with a single apical tooth.

Mentum: Two broad median' teeth w�th five pairs of lateral

teeth. Ventromental plates well developed with a setal

beard.

Mandible: Length 161.9 (153.6 - 215.1) urn. Apical one-third

dark brown. Three inner teeth. Ratio of apical tooth to

combined width of inner teeth 0.91 (0.75-1.07). Seta interna

present. Margins of mandible smooth.

Occipital margin: Similar in color to the rest of the head

capsule, two occipital projections present.

Body: Procerci approximately twice as long as wide, with

seven anal setae and two prominent spurs.

PUPA: n = 2

Color: Cephalothorax chestnut brown. Abdomen pale except

for lines delimiting segments.

Length: Total length 4.20-4.45 mm; abdomen length 3.12-3.37.

Cephalothorax: Dorsal surface slightly wrinkled. Cephalic

tubercles low rounded with frontal setae present. Thoracic

horn 325.4-364.8 urn long, with spines on the surface.

Abdomen: Segment II with Pedes spurii B present. Hook row

on tergite II of long apically hooked spines, half the width

of tergite. Tergites III to VI with a posterior row of blunt

,-

142

of spines.

Conjunctives of segments III/IV and IV/V with

Tergites IV, V and VI with paired medial patches

Lateral setae V-4, VI-4, VII-4 and VIII-5. Anal

spines.

spinules.

lobes with fringe of about 35 hairs each and three distally

positioned anal macrosetae.

BIOLOGICAL NOTES: Specimens were ,collected from aquatic

macrophytes and algal mats. The larval digestive tracts

contained filamentous algae, particularly from those

associated with the Clado£b� mats, diatoms and detritus.

REMARKS: The specimens key to E. sordidellus group in

Cranston (1982) and Cranston, � ale (1983). To confirm this

identification reared male material is required.

MATERIAL EXAMINED: Pond A: 5 larvae. Pond B: pupal exuvium;

2 larvae. Pond F: reared female.

Psectrocladius (Psectrocladius) sp. 2

(Figures 189 to 190)

LARVA: No larva were associated with the pupa.

PUPA: n = 2

Color: Dark brown lines separating the segments, remaining

areas transparent.

Length: Total length 6.0-6.8 mm, abdomen length 4.4-5.1 mm.

Cephalothorax: Dorsal surface slightly reticulated.

Cephalic tubercles are dome shaped with a long apical setae.

Thoracic horns 493-540 urn long, pale, with spines over the

surface.

Abdomen: Segment II with Pedes spurii B present. All

,__

I

143

tergites except I and VII with sparse fine shagreen.

Tergites II to VI with two posterior rows of spines. The

most anterior row is very strong, some are bifurcated. The

posterior row made of fine spines. Spine rows on tergites

II, III, and IV, are on distinct posterior extensions.

Tergites IV, V and VI with paired ,central patchs of spines,

increasing in size and number of spines caudally. Tergite

VII with a sparse posterior row of strong spines.

Conjunctives bare. Lateral setae VI-4, VII-4, VIII-S. Anal

lobes rounded with a hair fringe of 60 or more hairs and

seven·anal macrosetae.

BIOLOGICAL NOTES: The two pupal exuviae were collected from

pond A on May 26, 1983 and July 1, 1984.

REMARKS: The specimens key to Psectrocladius

(Psectrocladius) sp. in Wilson and McGill (1982) and to

Esect££cladiu� (E.) sp 3 in Mason (1983). Reared material is

needed for species identification.

MATERIAL EXAMINED: Pond A: 2 pupal exuvium.

�udosmittia Goetghebuer

Goetghebuer. 1932. Faune France. 23:126.

LARVA: Antennae with four or fewer segments, shorter than

half the length of the mandibles. Mentum with single median

tooth, with four pairs of lateral teeth. Ventromental plates

distinct, second pair of plates sometimes present, setal

beard absent. SI and SII bifid. Premandibles with two to

,-

I

144

four teeth. Pecten epipharyngis three simple or serrated

plates. Mandibles with three inner teeth, apical tooth

shorter than combined width of inner teeth. Seta interna

absent. Anterior parapods reduced and fused with apical

claws. Procerci absent, anal setae present.

parapods reduced or absent.

PUPA: Small. Exuvium almost transparent.

spinules. Tergites with extensive shagreen.

rounded and bare.

REMARKS: Most species are terrestrial or semi-terrestrial

(Oliver and Roussel. 1983).

Posterior

Conjunctives with

Anal lobes

The genus probably has a worldwide distribution and may

hav.e a number of species (Cranston, et a1. 1983). One

species has been previously recorded from the Nearctic

(Oliver 1981).

One species was collected in this study.

Pseudosmittia sp.

(Figure 191)

LARVAE: None collected.

PUPAE: n = 3

Color: �ale to tran�����nt.

Length: Total length 3.1 (2.7-3.5) mm; abdomen length 2.2

( 1 .9 - 2.5) mm.

Cephalothorax: Thoracic horns absent.

Abdomen: Segments with extensive shagreen, a narrow anterior

..

145

and a wider posterior band of stronger shagreen. Tergites II

to VII with a slight pad extending posteriorly with a number

of spinules on them. Intersegmental conjunctives with

spinules. Anal lobes bare.

BIOLOGICAL NOTES: Pupal exuviae were collected in late April

and late May.

REMARKS: The specimens key to ��itti� in Wilson and

McGill (1982) and Coffman (1984).

MATERIAL EXAMINED: Pond A: 2 pupal exuviae. Pond D: pupal

exuvium.

,--

146

ADDITIONAL RESULTS AND DISCUSSION

TEMPERATURE

The water temperature of pond A generally followed that

of the air temperature (Table 1). However the water never

reached the· high temperatures that the air did. In spring

and autu�n when air temperatures hlere low, water temperatures

were not as low.

WATER DEPTH

In pond A the water depth (Fig. 192) usually reached a

peak soon after the ice thawed from the surface of the water

and the snow from the surrounding land melted. The water

levels slowly and steadily decreased to a minimum in late

summer and early autumn.

During the study, two events occurred with respect to

water depth which had significant effects on the pond and its

organisms.

On June 24, 1983, a severe rainstorm raised the water

level of pond A from about 73 cm on June 15 to over 118 cm on

June 25. After the storm the pond water level slowly

declined during the remainder of the year but by freeze.up

the pond still had about 75 cm of water in it, almost the

level present at the spring peak in 1983. Effects of this

were observed in the spring of 1984, when, although spring

runoff was low, the spring water level was almost 20 cm

higher than it was in 1983.

After the storm of June 24, 1983, the water in pond A

I

147

remained very turbid for many weeks. Much of the pond margin

which had been dry in the spring was submerged and remained

so for almost the entire year. In these areas the

terrestrial and emergent vegetation that was damaged by the

storm began to decay.

The Orepan.2.£.!adius mat coverin.g the substrate in the

central region of the pond began to die, probably due to lack

of light for photosynthesis caused by the turbid water. The

subsequent decay caused anaerobic conditions as evidenced by

the unusually strong smell of hydrogen sulfide from samples

taken from this area.

8y July 17, 1983 very few chironomids were collected from

the benthos of the central region. However, large numbers of

late instar larvae of Chironomus te�� and QxlEtot�ndiE�

barbi��, which normally were collected from the benthos of

the central region" were collected from the newly submerged

area in the pond's'periphery where water depths were less

than 30 cm.

These observations suggest that as the benthic

microhabitat of the central area of the pond deteriorated the

usually sedentary larvae migrated to the more favourable

conditions around the edge of the pond. This agrees with,a

number of researchers who found similar behaviours occuring

in late instar larvae when conditions in the immediate

microhabitat deteriorated (Oavies 1973; Hynes 1961).

8y the spring of 1984 the distributiqn of chironomid

'-

,

148

larvae was back to a more "normal state", with larvae of the

two species 'being collected from the central benthos region,

and a new mat of ���ladi� had started to grow.

After the spring peak in 1984 the water level slowly

declined until September 10 when surface water disappeared

completely. Surface water was restored by autumn snow and

precipitation to a depth of 15 cm by freeze up.

The effects, if any; of this dry phase were not

determined. Potentially a number of species may have been

eliminated if they were unable to survive the total loss of

surface water (Wiggins � �l. 1980). However the amount of

d�ssication of the substrate in pond A may not have been

great enough to eliminate the drought sensitive species,

because the substrate under the dry crust was still quite

moist.

MICROHABITATS IN POND A

The seven general microhabitats distinguished in pond A

were: central and peripheral benthos, Q��ocladi� sp. mat,

submerged vegetation, algal mats, emergent vegetation, and

decaying Sali� wood.

The freeliving Tanypodinae were collected in all types of

microhabitats except the benthos and on decaying Sali�

branches. Specimens of �£otanypus alaskensis and

Ablabesmyia pulchri�nnis collected from benthic samples of

the central region were probably associated with the

�panocladius mat covering the substrate rather than the

,-

149

substrate itself. Larvae of most of the Tanypodinae were

collected from submerged vegetation, submerged stalks of

emergent vegetation and algal mats.

Some species of Chironominae showed very specific

microhabitat preferences. Chi�� !�nta� and

Q11B1ot�dip� £arbip� were almo�t exclusively collected

from samples of the benthos of the pond. These two species

are particularly adapted for life in low oxygen level by the

presence of haemoglobin in their haemolymph. Only during the

flood period in 1983 did the central benthos region become

uninhabitable because of very low oxygen levels.

Larvae of Di£�tendip� sp. were collected exclusively

from the submerged decaying Sali� branches found in the pond.

The Tanytarsini species fl������ sp.,

�at���� sp. and Tanytars� sp. 3 were collected from

the Cladophora sp. mats which were present in pond A in 1982.

The species of Orthocladiinae were all collected from

submerged macrophytes, submerged stems of emergent vegetation

and from fla£B£b£� mats.

FEEDING

From examination of the gut contents of the larvae

collected it appears the Chironomidae feed on a wide variety

of food.

The larvae of the Tanypodinae are to some extent

predaceous (Armitage 1968). This was evident in examination

of the larval guts. Most tanypod larvae contained detritus,

,

,

150

diatoms and filamentous algae and small crustaceans such as

ostracads and cladocerans and a number of orthoclad and

Chironominae larvae. One specimen of DerotanYE� ala�kensis

also contained the remains of a chironomid pupa, and a

specimen of E.:!ect�m� dyari had along with chironomid

larvae the remains of a leg of a trichopteran or coleopteran

in the gut.

In the larval guts of the Chironominae and Orthocladiinae

were found detritus, particularly in Chirono�� 1��� and

f11ptotendipes .Qarbipes, diatoms and filamentous algae.

Filamentous algae predominated in the guts of larvae

collected in association with the Cl�dophor� mats.

EMERGENCE

Four species had distinct peak emergences during the

study. ��yia �chriEenni� emerged mostly during June

and July. Chrio��� ten�� emerged throughout the open

water season but peaked from June to mid July. Gl�tendi�

barbipes emerged mostly during May and June but pupa� exuvaie

could be collected throughout__ ��e open water season.

Acricot£E� �� emerged in 1983 just after the ice thawed

from the surface in pond A in late April and early May. This

emergence was very large. However for the remainder of the

years the pond was studied no comparable emergence of �.

�� occurred.

From the patterns of emergence it appears that these four

species are univoltine in pond A.

,

-T-

151

NEW RECORDS OF SASKATCHEWAN POND CHIRONOMIDAE

Forty species of Chironomidae were collected from ponds

in this study. These included six Tanypodinae, 21

Chironominae (16 Chironomini and 5 Tanytarsini), and 13

Orthocladiinae. Only four of the 40 species were not

collected from pond A; Tanypus .E.!:!nctipennis from pond B,

Phaeno��� sp. from pond F, Hydr��� sp. 1 from pond 0,

and �drobaenus sp. 2 from pond C.

Of the forty species collected in this study (Table 2),

seven are additions to Driver's (1977) list of Saskatchewan

pond inhabiting chironomids: DerotaD1� �laskensis,

Erocladi� nietus, Tanypus E�ctipennis, Chrionomus �trell�,

f!�ptochironomus digitat�, Cricot0.E.!:!� ��tu�, and

Psect££�di� flavus. Five species; one named, four

unnamed; belong to genera not previously recorded from

Saskatchewan ponds; lanypus Eunctipenni�, Cl�£2�lm� sp.,

Cladotanyta� sp., f£rynoneura sp. and Eseudosmittia sp ••

,-

152

SUMMARY

Forty species of Chironomidae were collected from ponds

in the study (Table 2). These included six Tanypodinae, 21

Chironominae (16 Chironomini, 5 Tanytarsini) and 13

Orhtocladiinae. Only four of the ,40 species were not

collected from pond A, Tanypus B�ti�nnis from pond Band

PhaenoEsectra sp. from pond F, Hydroba��� sp. 1 from pond D

and Hydrobaenus sp. 2 from pond C.

Five genera and seven species were not previously listed

as inhabiting Saskatchewan ponds by Driver (1977).

Larvae and pupae were collected from pond A and other

selected ponds during 1982, 1983 and 1984. Representative

specimens were reared to adults.

Generic and species identification keys, generic

diagnoses and species descriptions are presented for the

chironomids collected in the study.

Prleiminary data on emergence patterns, microhabitat

distributions, and effects of water fluctuations on

chironomid distribution in Pond A are discussed.

Air a�d water temperatures and water depths were taken

on selected dates from Pond A during the. study.

,

,

153

CONCLUSIONS

The study of pond Chironomidae in Saskatchewan is at a

very preliminary stage. Only Driver (1977) has previously

studied chironomids inhabiting Saskatchewan ponds. Driver's

research and the present study clearly show chironomids are a

very important part of the pond aquatic insect diverity.

Most pond studies however deal with the chironomids, and most

other aquatic insects, at a supraspecific level or not at all

because the emphasis of previous pond studies has been on

mosquito control and waterfowl management. This neglect of

pond aquatic insects has and is hampering environmental

impact studies of agiicultural pesticides and other

pollutants on the pond community. Future research is needed

in the areas of species level taxonomy, life histories and

ecology. of pond aquatic insects before the impact of

agricultural pesticides on ponds can been accurately

assessed.

Another area which needs further attention is the

standardization of pond and wetland classification. At

present, communication between researchers is hampered by not

understanding'what is meant by the variety of terms used to

describe wetland systems. To develop an accurate terminology

a number of parameters must be taken into account such as

water chemistry, pond morphometry, vegetation, drainage,

association with other surface water and the stage in the wet

phase of the -ura t e r body. It is necessary to realize the

�-

154

important.effect this last parameter has on the flora and

fauna of the wetland. It must also be realized that single

season studies without prior information on a wetland provide

little information about its ecology or how it changes from

year to year and how these changes affect the organisms

inhabiting it. Long term studies.of ponds and other wetlands

will greatly improve our knowledge of these interesting and

constantly changing ecosytems.

1_

155

LITERATURE CITED

Alekseyv, N. K. 1965. Plankton feeding of Chironomidae

during the larval stage. Nauchnye Poklady U Ysshei

Shkoly, Biologichiskie Nauki 1:19-21

Alfred, J. R. B. 1974. On the food of fhiro�� £2stat�

(Chironomidae: Diptera) from,a shallow freshwater pond

in S. India. Freshw. BioI. 4:337-342

Ali, A. 1981. Laboratorry evaluation of organophosphates and

new synthetic pyrethroid insecticide against pestiferous

chironomid midges of central Florida. Mosq. News.

41:157-161.'

Anderson, J. F. and S. W. Hitchcock. 1968. Biology of

Chiro�� atrella in a tidal cove. Ann. Entomol. Soc.

America. 61:1597-1603.

Armitage, P. D. 1968. Some notes on the food of the

chironomid larvae of a shallow woodland lake in South

Finland. Ann. Zool. Fenn. 5:6-13

Ashe, P. 1983. A catalogue of chironomid genera and subgenera

of the world including synonyms (Diptera:Chironomidae).Ent. scand. Supple 20:1-68.

Barlocher, F., R. J. Mackey and G. B. Wiggins. 1978. Detritus

processing in a temporary vernal pool in southern'

Ontario. Arch. Hydrobiol. 81(3):269-295;

Beattie, D. M. 1978. Life cycle and changes in carbohydrate

protiens and lipids of £�nta�dil� l�lnatum Goet.

(Diptera: Chironomidae). Freshw. BioI. 8:109-113.

t._

156

�-

Beck, E. C. and W. M. Jr. Beck. 1969. Chironomidae (Diptera)

of Florida - III. The Harnischia complex (Chironominae).

Bull. Florida. st. MUs. BioI. Sci. 13:277-313.

Beck, W. M. Jr. 1977. Environmental requirements and

pollution tolerance of common freshwater Chironomidae.

Environ. Mon. and Support Lap. EPA-600/4-77-024. 258pp.

Beck, W. M. Jr. and E. C. Beck. 1966. Chironomidae (Oiptera)

of Florida.· 1. Peentaneurini (Tanypodinae). Bull.

Florida. State Mus. 10:305-379.

Beck, W. M. Jr. and E. C. Beck. 1�68. The concept of genus in

the family Chironomidae. Ann. Zool. Fenn. 5:14-16

Berg, C. O. 1950. Biology of certain Chironomidae reared from

Potomogeton. Ecol. Monogr. 20:83-101.

Brock, E. M. 1960. Mutualism between the midge Cric�!�E� and

the alga �ost0.E. Ecology 41(3):474-483.

Brower, J. E. and J. H. Zar. 1984. Field and laboratory

methods for general ecology. Wm. C. Brown Co. Dubuque,

Iowa. 194 pp.

Brundin, L. 1966. Transantarctic relationships and their

significance evidenced by thironomid midges. With a

monograph of the subfamilies Pononominae and

Aphroteniinae and ·t�e·�����al Heptagyniae. Kungl. S.

Veten. Handl. 11:1-472.

Brundin, L. 1983. Chilenomyia �ado� n. SPa and

Chienomyiinae, a new subfamily among the Chironomidae

(Diptera). Ent. Scand. 14:33-45.

157

Brundin, L. and O. A. Saether. 197B. �uchQ�l1� bu£��ni£� n.

sp. and Buchonomyiinae a new subfamily among the

Chironomidae (Oiptera). Zool. Scripta 17:269-275.

Bryce, O. and A. Hobart. 1972. The biology and identification

of the larvae of the Chironomidae (Oiptera). Entom. Gaz.

23:175-217.

Burrill, A. C. 1913. Economic and biological notes on the

giant midge fhirQ��� (Tendi�) .E.!!:!.!!!�� Meigen. Bull

Wisconsin. Nat. His. Soc. 10:124-163.

Butler, M. G. 1982. A seven year lif cycle for two Chir£���

species in arctic Alaskan tundra ponds (Oiptera:

Chironomidae). Can. J. Zool. 60:58-70.

Claassen, P. W. 1922. The larva of a chironomid

(Iri��cladi� �guit�� n. sp.) which is parasitic on a

mayfly nymph (Ri1h£E���sp). Kan. Univ. S. Bull.

14:395-405.

Coffman, W. P. and L. C. Ferrington Jr. 1984. Chapter 25.

Chironomidae. Pp. 551-652. � Merritt, R. W. and K. W.

Cummins, eds., Introduction to the Aquatic Insects of N.

America, 2nd edition. 722 pp. Kendall/Hunt Puplishing

Co., Oubuque, Iowa.

Cranston, P. S. 1982. A key to the larvae of the British

Orthocladiinae (Chironomidae). Freshw. BioI. Ass. Sci.

Pub. #45. 152 pp.

Cranston, P. S. 1983. 3. The larvae of Telmatogetnoinae

(Oiptera:Chironomidae) of the Holarctic region. - Keys

t,_

158

and diagnoses. Ent. scand. Supple 19:17-22.

Cranston, P. S., M. O. Gad El Rab and A. 8. Kay. 1981.

Chironomid midges as a cause of allergy in the Sudan.

Trans. R. Soc. Trop. Med. Hyg. 75:1-4.

Cranston, P •. S., D. R. Oliver and O. A. Saether. 1983. 9. The

larv�e of Orthocladiinae (Diptera: Chironomidae) of the

Holarctic region - Keys and diagnoses. Ent. Scand.

Supple 19:149-291.

Curry, L. L. 1958. Larvae and.pupae of the species of

Cryptochironomus (Diptera) in Michigan. Limno. Oceanogr.

3:427-442.

Curry, L. L. 1961. A key for the larval forms of aquatic

midges (Tendipidae:Diptera) found in Michigan. Atom.

Energy Com. Nat. Inst. Health. Rep. 1:1-162.

Daborn, G. R •. 1974. Biological features of an aestival pond

in western Canada. Hydrob. 44:287-299.

Daborn, G. R. 1976. Physical and chemical features of a

vernal temporary pond in western Canada. Hydrob.

51 :33-39.

Daborn, G. R. and H. F. Clifford. 1974. Physical and chemical

features of an aestival pond in western Canada. Hydrob.

�-

44:43-59.

Danks, H. V. 1971a. Overwintering of some north temperate and

arctic Chironomidae. Can. Ent. 103:589-604.

Danks, H. V. 1971b. Life history and biology of Ei�feldia

��hro� (Diptera:Chironomidae). Can. Ent.

159

103:1597-1606.

Danks, H. V. 1971c. Overwintering of some north temperate and

arctic Chironomidae. II Chironomini biology. Can. Ent.

103:1875-1910.

Danks, H. V. and J. W. Jones. 1978. Further observations of

winter cocoons in Chironomid�e (Diptera). Can. Ent.

110:667-669.

Davies, 8. R. 1973. The planktonic activity of larval

Chironomidae in Loch Leven, Kinross. Proc. R. Soc.

Edinburgh (8) 74: 275-283.

Davies, I. J. 1975. Selective feeding in some Arctic

Chironomidae. Verh. Internat. Verein. Limnol.

19:3149-3154.

Dickinson, J. C. Jr. 1949. An ecological reconnaissance of

the biota of some ponds and ditches in northern Florida.

Quart. J. Florida. Acad. Sciences. 11:1-28.

Donald, D. 8. 1971. The limnology and the plankton of three

temporary ponds in Alberta. Master's thesis, University

of Calgary, Calgary. 126 pp.

Dosdall, L. M. and P. G. Mason. 1981. A chironomid

(Nanocladius (Plecopteracoluth�) br.2nchi.£ol�: Diptera)

phoretic on a stonefly (�.££2�ria 11.£££ia�: Plecoptera)

in Saskatchewan. Can. Ent. 113:141-147.

Downes, J. A. 1969. The swarming and mating flight of

Diptera. Ann. Rev. Entomol 14:271-298.·

Downes, J. A. 1974. The feeding habits of .adult Chironomidae.

' ......

160

Ent. Tidskr. 95. Supple 84-90.

Driver, E. A. 1977. Chironomid communities in small prairie

ponds: some characteristics and controls. Freshw. 8iol.

7:121-133.

Driver, E. A. and D. G. Peden. ,1977. The chemistry of surface

water in prairie ponds. Hydr9b. 53:33-48.

Dumbleton, L. J. 1973. An ice chironomid. N. Zealand.

Entomol. 5:131-133.

Edward, D. H. 1968. Chironomidae in temporary freshwater.

Australian Soc. Limnol. 6:3-5.

Edwards, F. W. 1929. British non-biting midges

(Diptera:Chironomidae). R. Entomol. Soc. Lond. Trans.

77:279-430.

Fagan, E. B. and W. R. Enns. 1966. The distribution and

biology of aquatic midges in, Missouri laggons. Proc.

Entomol. Soc. of Washington. 68:277-289.

Fittkau, E. J. 1962. Die Tanypodinae (Diptera Chiromonidae);

(Die Tribus Anatopyniini, Macropelopiini und

Pentaneurini). Abh. Larvalsyst. Insekten 6:1-453.

Fittkau, E. J. 1966. Kleine Mitteilung. Chironomus, nicht

Tendipes. Arch. Hydrobiol. 62:269-271.

Fittkau, E. J., and S. S. Roback. 1983. 5. The larvae of

Tanypodinae (Diptera: Chironomidae of the Holarctic

Region - Keys and diagnoses. Ent. scand. Supple

19:33-110.

Forsyth, D. J. and I. D. McCallum. 1978. Xenochironomus

,-

161

�nt���nsis (Diptera:Chironomidae) an insectan

inquiline commensal of �rid� ���zie�l

(Mollusca:Lamellibranchia). J. Zool. London.

186:331-334.

Furnish, J., D. Bellack, D. Baker and B. A. Pennigton. 1981.

Phoretic relationships between f£!ydal� E£!�tus

(Megaloptera:Corydalidae) and Chironomidae in eastern

Tenenssee. Ann. Entomol. Soc. Am. 74:29-30.

Gerking, S. D., A. Berg. and P. Gerard. 1975. Rate of

sediment intake by midge larvae fbironomus £l����

(Diptera) using a 134Cs tracer. Pages 126-135. 1�

Cushing, C. E. ed., Radioecology and Energy Resources.

Dowden, Hutchison and Ross Inc. Stroudsburg.

Gibson, N. H. E. and L. Lloyd. 1945. On the mating swarms of

certain Chironomidae (Diptera). Trans. R. Ent. Soc.

Land. 95 (Part 6):263-294.

Gillespie, J. M. 1974. A biosystematic study of Idaho

Chironomini (Oiptera: Chironomidae). Doctoral thesis,

University of Idaho, Moscow. 389 pp.

Gillies, M. T. 1951. Association of a chironomid ('Diptera)larva with IE�� £�ica L. Ephemeroptera.

Entomologist's Monthly Magazine 87:200-201.

Gregory, L. A. and J. S. Loch. 1973. Abenthos survey (1972)

in the North Saskatchewan River in the vicinity of the

Prince Albert Pulp Company, Prince Albert, Saskatchewan.

Environ. Canada Fish. and Mar. Tech. Rep. S. No.

,_

162

CENT-73-2. 17 pp.

Grodhaus, G. 1976. Two species of Eha�£E�ct!� with drought

resistant larvae (Oiptera:Chironomidae). J. Kan. Ent.

Soc. 49:405-418.

Grodhaus, G. 1980. Aestivating chironomid larvae associated

with vernal pools. Pages 315�322. In Murry, O. A. ed.,

Chironomidae. Ecology, Systematics, Cytology and

Physiology. 354 pp. Pergamon Press, New York.

Hamilton, A. L. 1961. The macroscopic botton fauna of Kenose

Lake. Master's thesis. University of Saskatchewan,

Saskatoon. 69 pp.

Hartland-Rowe, R. 1966. The fauna and ecology of temporary

pools in western Canada. Verh. Internat. Verein. Linmol.

16:577-584.

Hirvenjoa, M. 1973. Revision der Guttung Cricot�£� van deer

Wulp und ihrer Verwandten (Oiptera:Chironomidae) Ann.

Zool. Fenn. 10:1-363. Adapted and translated by Simpson,

K. W., R. W. 80de and P. Albu. 1983. New York St. Mus.

Bul. #450. Pp. 133.

Hynes, H. B. N. 1961. The effect of water fluctuations on

littoral fauna. Verh. Internat. Verein. theor. angeu.

Limnol. 14:652-656.

Johannsen, O. A� 1937a. Aquatic Oiptera III. Chironomidae

Subfamilies Tanypodinae, Oiamesinae, and Orthocladiinae.

Mem. Cornell. Uni. Agric. Exp. St. 205:3-84.

Johannsen, O. A. 1937b. Aquatic Oiptera IV. Chrionomidae.

,_

163

Subfamily Chironominae. Mem. Cornell. Uni. Agric. Exp.

St. 210:3-56.

Johannsen, o. A. and H. K. Townes 1952. Diptera of

Connecticut - Tendipdidae (Chironomidae) 1�. Troxell, E.

L. ed. Guide to the insects of Connecticut VI Bull.

Connecticut St. Geol. Nat. H�s. Surv. 80:3-148.

Johnson, G. D. and M. S. Mulla. 1982. An aquatic macrophyte

affecting nusiance chironomid midges in a warmwater

lake. Environ. Entomol. 12:266-269.

Judd, W. W. 1964. A study of the population of insects

emerging as adults from Saunders Pond at London,

Ontario. Amer. MidI. Nat. 71: 402-414.

Kenk, R. 1949. The animal life of temporary and permanent

ponds in southern Michigan. Misc. Publ. of Mus. of Zool.

Uni. of Michigan #71:1-66.

Kurazhkovskaya, T. N. 1971. On the biology of Q11E!otendi�

�ari� Goetgh. Limnol. 8:219-220.

Leathers, A. L. 1916. Silk spinning in its relation to the

feeding habits of Chir.Q.Q'£!!!'!:!..2 lobif�..!::!..2 Say. Science.

43:183.

Lehmkuhl, D. M., H. V. Danks, V. M. Behan-Pelletier, D. J.

L a r son, D. M. R as e n b erg, 'a n d I. M. S m i t h '.' 1984.

Reccommendations for the appraisal of environomental

disturbance: Some general guideelines and the value and

feasiblity of insect studiees. Supp. Bull. Ent. Soc.

Canada. 16. 8 pp.

,-

164

Luferov, V. P. 1971. The role of light in the populating of

water bodies by epibiotic chironomid larvae.

Limnologica. 8:139-140.

Macan, T. T. 1966. The influence of predation.on the fauna of

a moorland fishpond. Arch. Hydrob. 61:432-452.

Macan, T. T. 1977. A twenty year study of the fauna in the

vegetation of a moorland fishpond. Arch. Hydrob.

81:1-24.

Mackey, A. P. 1979. Trophic dependancies of some larval

Chironomidae (Oiptera) and fish speices in the river

Thames. Hydrob. 62:241-247.

MacMillan, w. O. 1971. The early succeession of bottom fauna

in a new resivoir, Black Strap Lake, Saskatchewan.

Master's thesis. Univestiy of Saskatchewan, Saskatoon.

136 pp.

Mancini, E. R. 1979. A phoretic relationship between. a

chironomid larva and an operculate stream snail. Ent.

News. 90:33-36.

Manson, P. W., G. M. Sehwartz and E. R. Alred. 1968. Some

aspects of the hydrology of ponds and small lakes. Minn.

Agric. Exp. Sta. Tech. Bull. #257:1-88.

Mason, P. G. 1978. Biosystematics of Saskatchewan River

Chironomini. Master's thesis, University of

Saskatchewan, Saskatoon. 456 pp.

Mason, P. G. 1983. Systematics and ecology of Chironomidae

(Oiptera) associate� with Tobin Lake Reservior and the

,-

165

Saskatchewan River. Doctoral thesis, University of

Saskatchewan, Saskatoon. 771 pp.

McCauley, V. J. E. 1974. Instar differentiation in larval

Chironomidae (Diptera). Can. Ent. 106:179-200.

Mendis, A. S. 1956. A limnological comparison of four lakes

in central Saskatchewan.· Master's thesis, University of

Saskatchewan, Saskatoon. 103 pp.

Millar, J. B. 1973. Vegetation changes in shallow marsh wet

lands under improving moisture regime. Can •. J. Bot.

51 :1443-1457.

Mitsch, W. J., J. W. Day Jr., J. R. Taylor and C. Madden.

1982. Models of �orth America freshwater wetlands. Int.

J. Ecol. Environ. Sci. 8:109-140.

Morgan, M. J. 1949. The metamorphosis and ecology of some

species of Tanypodinae (Diptera:Chironomidae). Entmol.

Mon. Mag. 85:119-126.

Mozley, A. 1932. A biological study of a temporary pond in

Western Canada. Amer. Nat. 66:235-249.

Oliver, D. R. 1971. Life history of the Chironomidae. Ann.

Rev. Ent� 16:211-230.

Oliver, D� R. 1981. Chapter 29. Chironomidae. Pp. 423-458. l!:!

McAlpine, J. F. , B. V. Peterson, G. E. Shewell, H. J.

Teshey, J. R. Vockeroth and D. M Woods, eds., Manual of

Nearctic Diptera Vol. 1. Research Branch, Agriculture

Canada, Monog. No. 27. 674 pp.

Oliver, D. R., M. E. Roussel. 1983. The insects and arachnids

1_

166

of Canada. Part 11. The genera of larval midges of

Canada (Oiptera: Chironomidae). Agiculture Canada

Publication 1746. 263 pp.

Paine, G. H. Jr. and A. R. Gaufin. 1956. Aquatic Oiptera as

indicators of pollution in a midwestern stream. Ohio J.

Sciences 56:291-304.

Paterson, C. G. and C. J. Cameron. 1982. Seasonal dynamics

and ecologi�al strategies of the pitcher plant

chironomid, �etrio��� nabi Coq.

(Oiptera:Chironomidae), in southeast New Brunswick. Can.

J. Zool. 60:3075-3083.

Peckham, V. 1971.' Notes on the chironomid midge Belgica

antarcti� Jacobs at Avers Island in the maritime

Antarctic. Pac. Insects Mono. 25:146-166.

Pinder, L. C. V. 1978. A key to the adult midges of the

Britich Chironomidae (Oiptera) the non-biting midges.

Vol. I and II. Freshw. BioI. Ass. Sci. Pub. #37 169 pp.,

189 fig.

Pinder, L. C. V. 1983. 1. The larvae of Chironomidae

(Oiptera) of the Holarctic region - Introduction. Ent.

scand. Supple 19:7-10.

Pinder, L. C. V., and F. Reiss. 1983. 10. The larvae of

Chironominae (Oiptera: Chironomidae) of the Holoarctic.

- Keys and diagnoses. Ent scand. Supple 19:293-435.

Rasmussen, J. B. 1984. The life-history, distribution and

production of Chrironomus riparius and GI�£!ot�dipes

'-

J

167

�ri�� in a prairie pond. Hydrob. 119:65-72.

Rasmussen, J. B. 1985. Effects of density and microdetritus

enrichment on the growth of chironomid larvae in a small

pond. Can. J. Fish. and Aqu. Sci. 42:1418-1422.

Reist, A. and J. Fischer. 1979. Ecological and biometrical

investigation Chir���� larvae (Oiptera) from Lake

Wahlen near Berne. Rev. Sui. Zool. 86: 893-899.

Rempel, J. G. 1936. The life history and morphology of

fbir��� b��£��. J. BioI. Bd. Canada 2:209-221.

Rempel, J. G. 1937. A new species of the subgenus.

Kribi�� (Diptera:Chironomidae). Can. Ent.

69:274-275.

Roback, S. S. 1957. The immature Tendipedids of the

Phiadelphia area (Oiptera:Tendipedidae). Mono. Acad.

Nat. Sci. Phil. #9, 152 pp and 28 plates.

Roback, S. S •. 1971. The Subfamily Tanypodinae in North

America. Mono. Acad. Nat. Sci. Phil. #17, 410 pp.

Roback, S. S. 1976. The immature chironomids of the eastern

United States. I: Introduction and Tanypodinae -

Coelotanypodini. Proc. Acad. Nat. Sci. Phil.

127:147-201.

Roback, S. S. 1977. The immature chironomids of the eastern

United States. II Tanypodinae, Tanypodini. Proc. Acad.

Nat. Sci. Phil. 128:55-87.

Roback, S. S. 1978. The immature chironomids of the eastern

United States. III: Tanypodinae - Anatopyniini,

1-

168

Macropelopiini and Natarsiini. Proc. Acad. Nat. Sci.

Phil. 129:151-202.

Roback, S. S. 1980. The immature chironomids ·of the eastern

United States. IV: Tanypodinae - Procladiini. Proc.

Acad. Nat. Sci. Phil. 132:1-63.

Roback, S. S. 1983. _ablabesmyia (sartai,2) metica. A new

subgenus and species (Oiptera: Chironomidae:

Tanypodinae). Proc. Acad. Nat. Sci. Phil. 135:236-240.

Simpson, K. W. and R. W. Bode. 1980. Common larvae of

Chironomidae (Oiptera) from New York State streams and

rivers, with particular reference to the fauna of

artificial substrates. N. York St. Mus. Bull. #439, 105

'-

pp.

Saether, O. A. 1976. Revision of �drob���, lris�££ladiu§,

Zalutschia, Paratrisso£1adi� and some related genera

(Oiptera:Chironomidae). Bull. Fish. Res. Bd. Can. 195.

287 pp.

Saether, O. A. 1977. Female genitalia in Chironomidae and

other Nematocera: Morphology, phylogenies, keys. Bull.

Fish. Res. Bd. Can. 196:1-143.

Saether, 0 A. 1980. Glossary of chironomid morphology

terminology (Oipter�:·C�i���omidae). Ent. scand. Supple

14:1-51.

Soldan, T. 1978. Die Wirtsspezifizitat und Verbreitung von

Symbioclius £ithrogenae (Oiptera:Chironomidae) in der

Tschechoslowakei. Acta. entomol. bohemoslavaca 75:194.

169

steffan, A. W. 1965. On the epizoic associations of

Chironomidae (Diptera) and their phyletic relationships.

Pp. 77 to 78. 12 the Intern. Congr. of Ent. London Vol.

I.

Steiner, J. W., J. S. Doughman and C. R. Moore. 1982. A

gerneric guide to the larvae.of the Nearctic

Tanytarsini. U. S. Dept. Interior Geol. Surv. 82-768. 40

pp�

Stewart, R. E. and H. A. Kantrud. 1969. Proposed

classification of potholes in the glaciated prairie

region. Sask. Wetl. Sem. Can. Wild. Sere Report

#6:57-69.

Sublette, J. E. and M. S. Sublette. 1965. Family Chironomidae

(Tendipedidae). Pp 143 to 181. lD Stone, A. � �1. A

catalogue of Diptera of America north of Mexico. U. S.

Dept. of Agric. Handbook 276. 1696 pp.

Sugg, J. S. Edwards and J. Baust. 1983. Phenology and life

history of �gica antarcti�, an Antartica midge

(Diptera:Chironomidae). Ecol. Ent. 8:105-113.

Sugimoto, T. 1966. Relation of decrease of water surface

level and survival of egg mass of Te�iE� B��alis

Meigen. Kyto Saikyo Uni., Fac. Agric. Sci. Reports.

18:63-69.

Svensson, B. S. 1980. The effect of host density on the

succes of commensalistic �Riocladi� flave�

(Chironomidae) in utilizing streamliving fE�� Benri�

,-

170

(Ephemeroptera). Dikos 34:326-336.

Swanson, S. M. 1978. Ecology and production of macrobenthos

of Waldsea· Lake, Saskatchewan, with emphasis on

f£icotop� £!�� (Oiptera:Chironomidae). Master's

thesis, University of Saskatchewan, Saskatoon. 238 pp.

Syrjamaki, j. 1965. Laboratory studies on the swarming

behaviour of fhiro�� stre�kei Fittkau in litt. Ann.

Zool. Fenn. 2:145-152.

Thompson, G., J. Coldrey, and G. Bernard. 1984. The pond. The

MIT Press Cambridge, .Mass. 256 pp.

Tones, P. I. 1970. Pollution of the North Saskatchewan Ri�er

by the Prince Albert Pulp Company Limited. Master's

thesis, University of Saskatchewan, Saskatoon. 84 pp.

Townes, H. K. Jr. 1945. The Nearctic species of Tendipidini

[Oiptera, Tendipidae (=Chironomidae)]. Amer. MidI. Nat.

34:1-206.

Walshe, B. M. 1951. The feeding habits of certain chironomid

larvae (subfamily Tendipedinae). Proc. Zool. Soc. Land.

121 :63-79.

Warwick, W. F. 1967. Some chemical and biological aspects of

water pollution in the upper Qu'Apple River system.

Master's thesis, University of Saskatchewan, Saskatoon.

174 pp ,

Warwick, W. F. 1979. Pasqua Lake; southeastern Saskatchewan;

a preliminary assessment of trophic status and

contamination based on the Chironomidae (Oiptera). Pp.

,-

170a

255 to 267. � Murry, O. A. ed., Chironomidae. Ecology,

Systematics, Cytology and Physiology. 354 pp. Pregamon

Press, New York.

Webb, C. J. and A. Scholl. 1985. Identification of larvae of

European species of Chironomus Meigen

(Oiptera:Chironomidae) by mo�phological characters.

System. Entomol. 10:353-372.

Weissman, O. and J. D. Edman. 1980. Feeding by the adult

midge Chironomus thummi on dry sugar significantly

increase median longevity in both sexes. Mosq. News.

40:298-300.

Wetzel, R. G. 1983. Limnology, 2nd ed. Saunders College Publ.

767 pp.

White, T. R., J. S. Weaver III and R. C. Fox. 1980. Phoretic

relationships between Chironomidae (Diptera) and benthic

macroinvertebrates. Ent. News. 91:69-74.

Wiggins, G. 8., R. J. Mackey and I. M. Smith. 1980.

Evolutionary and ecological strategies of animals in

annual temporary pools. Arch. Hydrob./Suppl. 58 1/2

97-206.

Wilson, R. S. and J. O. McGill. 1982. A practical key to the

genera of pupal exuviae of the British Chironomidae

(Oiptera:Insects). University of Bristol Press. 62 pp.

Wirth, W. W. 1957. The species of Cricotopus midges living in

the blue-green alga Nostoc in California. Pan-Pac.

Entmol. 33:121-126.

'-

170b

Yoshimatsu, H. 1967. Feeding habits of the larvae of

.

Chironomus· �£!salis. Bio. Inst. fac. Lib. Arts

Yamaguchi. Uni. 115-125

".......

171

Figure 1 Map of Pond A

e

ee

ee

e

e

e

e

e

e �.e

Open Water

Vegetation 010m

172

Figure 2

138'V1

Slide Preparation

,.-

173

Figure 3 Larva

Thorax------------------�Anterior Parapods

L-4 seta

Lateral Hair Fringe

Lateral Process

Posterior Parapods

����----------Anal Tubules

Procerci

'1

174

Figure 4

TanypodinaeHead Capsule

��--------------- Lauterborn organ

Antenna

Mandible�j_-------

Basal tooth

������__--=======MaXillary palp

����-4��Jr----------M-appendage��__�����r----------Pseudoradula

,Q�::..t::::;::--:.�4-----....;.._ Do r sam en tum

�--���-�----- Para Ii gu la

__����t:::--����-------Pecten hypopharyngis

Ligula

��-------Eye spot

L-__----------�Antennal blade

figure 5

Cl1ironominaeHeod Capsule

Antennal blade

Lauterborn organ

Seta Antenna

Dorsal toothMandible

mandibularis

epipharyngis

palp

subdentalis

interna

Ventromental plate

....... 0'."

, j j

Figure 6 175

Pupal Cephalothorax

�� Cephalic Tubercle

l-__-------Thoracic Horn'

�__-----Dorsal Surface

Antennal Sheath

Wing Sheath

-t-------Leg Sheath

Figure 7

Pupal Abdomen

lt�-- Spine Tract

Shagreen

�::���r--------------Lateral Setae

�h�==��---------------SpurI---tii------------- G en ita 1 Sac

.....t!iI!'---------- Ana 1 Lob e

Hair Fringe�--------------------Macrosetae

176

Figures 8 to 12: Ablabes�yia pulchripennis. Fig. 8. Larval

antenna. Fig. 9. Larval hypopharyngis, paraligula

and ligula. Fig. 10. Larval mandible. Fig. 11.

larval maxillary palp. Fig. 12. Pupal anal lobes •

..

177

Figure 13: Ablabesmyia pulchripennis. Thoracic horns (pp -

plastron plate) and thoraxkamm (t).

Figure 14: Ablabesmyia pulchripennis. Pupal abdominal

tergites I to IV (arrow indicates scar on tergite

I ) .

Figure 15: Ablabesmyia pulchripennis. Pupal abdominal

tergites V to VIII and anal lobes.

-

•

..

16

_ .

-, ': .. _:." .... ,

:.' ;. :-

.,..

",', .- ':"

""

r ..

.

,:.

.

..

179

Figures 16 to 21: Derotanypus alaskensis. Fig. 16. Larval

antenna (bl - antennal blade). Fig. 17. Larval

Larval dorsomentum. Fig. 19. Larval mandible.

hypopharyngis, ligula and paraligula. Fig. 18.

Fig. 20. Simple claw of larval posterior parapod.

Fig. 21. Arched claw of larval posterior parapod •

.......

180

Figure 22: Derotanypus alaskensis. Pupal thoracic horn.

Figure 23: Derotan�pus alaskensis. Pupal abdominal tergites

I to IV.

Figure 24: Derotanypus alaskensis. Pupal abdominal tergites

VI to VIII and anal lobes.

.....

182

25

27

�

28

antenna. Fig. 26. Larval paraligula and ligula.

Figures 25 to 28: Pr�E1�di� niet�. Fig. 25. Larval

F�g. 27. Left side of larval dorsomentum. Fig. 28.

Larval mandible.

I .

Figur� 29: Procladius nietus.

Figure 30: Procladius nietus.

VIII and anal lobes.

183

Pupal thoracic horns.

Pupal abdominal tergites V to

..·f •

185

32

3S

II

I,

Figures 31 to 35: Procladius (!:!.) sp , Fig. 31. Larval

antenna. Fig. 32. Larval ligula and paraligula.

Fig. 33: Larval pecten hypopharyngis. Fig. 34.

Larval dorsomentum. Fig. 35. Larval mandible.

, �

Figure 36: .Procladius (�.) sp.

Figure 37: Procladius (�.) sp.

anal lobes.

186

Pupal thoracic horn.

Pupal tergites V to VIII and

'-

188

38

40

Figures 38 to 40: Esectrotan� Qyari. Fig. 38. Larval

antenna. Fig. 39. Larval dorsomentum (d),

paraligula (p), ligula and pecten hypopharyngis.

fig. 40. Larval mandible •

.....

189

Figure 41: Psectrotanypus dyari. Pupal thoracic horn.

Figure 42: Psectrotanypus dyari. Pupal abdominal tergites I

to V (arrow indicates scar on tergite I).

Figure 43: Psectrotanypus dyari. Pupal abdominal tergites

VI to VIII and anal lobes.

.-

u:; !Ill")

II.

"b't

tie' IrifP ........r

191

44

46

t-r-:

47

Figures 44 to 47: Tanxpus punctipennis. Fig. 44. Larval

antenna. Fig. 45. Larval paraligula and ligula.

Fig. 46. Larval dorsomentum. Fig. 47. Larval

mandible.

192

48�49

Si

52

Figures 48 to 52: Chironomus atrella. Fig. 48. Larval 51.

Fig. 49. Larval ventromentum and mentum. Fig 50.

seta interna). Fig. 51. Pupal cephalic tubercle

Larval mandible (pm - pecten mandibularis; Si -

(fs - frontal seta). Fig. 52. Spur on pupal

segment VIII.

53

193

58

59

Figures 53 to 59: Chironomus riparius. Fig. 53. Larval

antenna. Fig. 54. Larval mentum and ventromen�um.

Fig. 55. Larval 51. Fig. 56. Larval pecten

epipharyngis. Fig. 57. Larval mandible (dt -

dorsal tooth; ssd - seta subdentalis). Fig. 58.

Pupal cephalic tubercle. Fig. 59. Spur on pupal

abdominal segment VIII.

194

Figure 60: Chironomus atrella. Pupal abdominal tergites II

to VI.

Figure 61: Chironomus riparius. Pupal abdominal tergites

III to VI.

I

67

63�

65

ro

196

64�

68

Figures 62 to 69: Chironomus tentans. Fig. 62. Larval

antenna (ro - ring organ). Fig. 63. Larval SI.

Fig. 64. Larval pecten epipharyngis. Fig. 65.

Larval premandible. Fig� 66. Larval mandible.

Fig. 67. Larval ventromentum and mentum. Fig. 68.

Pupal cephalic tubercle. Fig. 69. Spur or. pupal

abdominal segment VIII.

...

r197

Figure 70: Chironomus tentans. Pupal abdominal segments III

to V.

Figure 71: Chironomus tentans. Pupal abdominal segments VII

and VIII and anal lobes.

-

199

Figure 72: Chironomus sp. Pupal abdominal segments III to

V.

Figure 73: Chironomus sp. Pupal abdominal segments VII and

VIII (arrow indicates spur).

-

201

Figure 74: Cladopelma sp. 1. Pupal abdominal segments

(arrow indicates mace process on tergite VI).

--.

-

,

75

77

203

76

Figures 75 to 77: Cladopelma SPa 2. Fig. 75. Larval

antenna. Fig. 76. Larval ventromentum and mentum.

Fig. 77. Larval mandible.

f_

204

78 80

81

Figures 78 to 81: Cryptochironomus digitatus. Fig. 78.

Larval antenna. Fig. 79. Larval premandible. Fig.

80. Larval ventromentum and mentum. Fig. 81.

Larval mandible.

•

205

Figure 82: Cryptochironomus digitatus. Pupal cephalic

tubercles.

Figure 83: Cryptochironomus digitatus. Pupal abdominal

segment VIII and anallobes (arrow indicates anal

lobe process).

Figure 84: Cryptochironomus digitatus. Pupal abdominal

tergites III and IV.

L

...

207

85

86 c;;\N)

88

87

Figures 85 to 89: Dicrotendipes sp. Fig. 85. Larval

antenna. Fig. 86. Larval pecten epipharyngis.

Fig. 87. Larval premandible. Fig. 88. Larval

ventromentum and mentum. Fig. 89. Larval mandible.

208

90

93 94

Figures 90 to 95: Einfeldia sp. Fig. 90. Larval antenna (10

- Lauterborn's organ). Fig. 91. Larval SI. 'Fig.

92. Larval frontal apotome. Fig. 93. Larval

ventromentum and mentum. Fig. 94. Larval mandible.

Fig. 95. Pupal spur on segment VIII.

,-

209

Figure 96: Einfeldia sp. Pupal abdominal tergites II to V.

..

�•

1

211

98 � 99

101�."•..._--.-- ... --�-:�...�

102

Figures 97 to 102: Endochironomus nigricans. Fig. 97.

Larval antenna. Fig. 98. Larval pecten

epipharyngis. Fig. 99. Larval premandible. Fig.

100. Larval ventromentum. Fig. 101. Larval

mentum. Fig. 102. Larval mandible.

....

212

Figure 103: Endochironomus nigricans. Pupal abdominal

tergites III to V.

Figure 104: Endochironomus niqricans. Pupal abdominal

tergites VI to VIII a nd anal lobes (arrow

indicates setal tuft of hair fringe).

,

. -

..

..

...

•

t. ·1

105

214

I06�� 107 r;;;;;:;:;:?

108

109

Figures 105 to 109: Glyptotendipes barbipes. Fig. 105.

Larval antenna. Fig. 106. Larval 51. Fig. 107.

Larval pecten epipharyngis. Fig. 108. Larval

ventromentum and mentum. Fig. 109. Larval

mandible.

_..--

215

Figure 110: Ql.i.EtotendiE� barbiE�. Pupal abdominal

tergites III to V (arrow indicates mace process on

tergite V).

Figure 111: Qly£igtendiE� sp. Pupal abdominal tergites III

to VI.

-

\

i·

217

Figure 112: Parachironomus sp. 1. Pupal abdominal tergites

IV to VIII and anal lobes.

Figure 113: Parachironomus sp. 2. Pupal abdominal tergites

V to VIII and anal lobes.

219

114 115�

116

Figures 114 to 117: Parachironomus sp. 3. Fig 114. Larval

antenna. Fig. 115. Larval pecten epipharyngis.

Fig. 116. Larval ventromentum and mentum. Fig.

117. Larval mandible.

220

118 119

120 121

Figures 118 to 121: Phaenopsectra sp. Fig. 118. Larval

antenna. Fig. 119. Larval pecten epipharyngis.

Fig. 120. Larval ventromentum and mentum. Fig.

121. Larval mandible.

- ...

221

122

123�ifJw" .

�\�124�

125at

126

127

�

Figures 122 to 127: Cladotanytarsus sp. Fig. 122. Larval

antenna (at - antennal tubercle). Fig. 123. Larval

S1. Fig. 124. Larval pecten epipharyngis. Fig.

125. Larval ventromentum and mentum� Fig. 126.

Larval mandible. Fig. 127. Claw on larval

posterior parapods.

132

222

129 .

130�

13)

Figures 128 to 132: Paratanytarsus sp. Fig. 128. larval

antenna. Fig. 129. larval 51. Fig. 130. larval

premandible (pmb - premandibular brush). Fig. 131.

Larval ventromentum and mentum. Fig. 132. Larval

mandible.

223

Figure 133: Tanytarsus sp. 1. Pupal cephalothorax (arrow

indicates thoracic horn).

Figure 134: Tanytarsus sp. 1. Pupal abdominal tergites III

to VIII and anal lobes.

J

...

225

Figure 135: Tanytarsus sp. 2. Pupal abdomen.

-

-

�

138Q..

.....

139...

. , .

.

:.� �

140

Figures 136 to 140: Tanytarsus sp. 3. Fig. 136. Larval

antenna (p - petioles of Lauterborn's orgar.s).

Fig. 137. Larval 51. Fig. 138. Larval pecten

epipharyngis. Fig. 139. Larval ventromentum and

. mentum. Fig. 140. Larval mancible •

, 228

141 142

� 14�

144

Figures 141 ·to 145:

antenna.

Acricotopus senex.

Fig. 142. Larval 51.

Fig. 141. Larval

Fig. 143. Larval

premandible. Fig. 144. Larval ventromentum and

mentum. Fig. 145. Larval mandible.

229

Figure 146: Acricotopus senex. Pupal thoracic horn (arrow

indicates thoracic horn).

Figure 147: Acricotopus senex. Pupal abdominal tergites III

to VIII and anal lobes.

_t

•

147.....

231

Figure 148: Corynoneura sp. 1. Pupal abdominal tergites III

to VIII and anal lobes (arrow indicates lamallar

setae).

233

1.49

151 152sh

Figures 149 to 152: Co£X��� sp. 2. Fig. 149. larval

\

anten�a (sh - sensory hair). Fig. 150. Larval

mentum. Fig. 151. larval mandible. Fig. 152. Spur

on larval posterior parapods.

• -__......-----

234

153 154' 155[}JJ

.15�.158

Figures 153 to 159: Cricotopus o r na t u s , Fig. 153. Larval

antenna. Fig. 154. Larval SI. Fig. 155. Larval

pecten epipharyngis. Fig. 156. Larval premandible.

Fig. 157. Larval ventromentum and mentum. Fig.

158. Larval mandible. Fig 159. L-4 seta on larval

abdominal segment v.

Figure 160: Cri£2topus ornatus.

(arrow).

Figure 161: Cricotopus ornatus.

to VIII.

-

Pupal thoracic horn

Pupal abdominal tergites II

237

Figure 162: Cricotopus sp. 1. Pupal thoracic horn (arrow

indicates thoracic horn).

Figure 163: Cricotopus sp. 1. Pupal abdomen.

..

239

Figure 164: Cricotopus sp. 2. Pupal thoracic horn (arrow).

Figure 165: Cricotopus sp. 2. Pupal abdominal tergites III

to VIII and anal lobes.

-

•

,

165

241

166 168�

Figures 166 to 170: Hydrobaenus sp. 2. Fig. Larval antenna.

Fig. 167. Larval 51. Fig. 168. Larval premandible.

Fig. 169. Larval ventromentum and mentum. Fig.

170. Larval mandible.

-

wII'..

242

Figure 171: Hydrobaenus sp. 1. Pupal abdominal tergites III

to VIII and anal lobes.

Figure 172: Limnophyes sp. Pupal abdominal tergites III to

VIII and anal lobes (arrow indicates long posterior

band of setae on tergite VI).

�.----------------------------

J7� � 175�244

176

Figures 173 to 178: Psectrocladius flavus. Fig. 173. Larval

antenna. Fig. 174. Larval s r , Fig. 175. Larval

premandible. Fig. 176. Larval ventromentum and

mentum. Fig. 177. Larval mandible. Fig. 178.

Larval pro cercus (sp - spur on procercus).

245

Figure 179: Psectrocladius flavus. Pupal thoracic horn

(arrow indicates thoracic horn).

Figure 180: Psectrocladius flavus. Pupal abdominal tergites

II to V.

Figure 181: Psectrocladius flavus. Pupal abdominal tergites

V to VIII and anal lobes (arrow indicates lamallar

setae on tergite VII).

182 �; ::�''..

.....f;":�t:J

183 �

247

,

Figures 182 to 186: Psectrocladius SPa 1. Fig. 182. Larval

antenna. Fig. 183. Larval 51. Fig. 184. Larval

premandible. Fig. 185. larval ventromentum and

mentum. Fig. 186. Larval mandi�le.

248

Figure 187: £sectr££1adiu� sp. 1. Pupal thoracic horn.

Figure 188: £sectrocladius sp. 1. Pupal abdominal tergites

II to VIII and anal lobes (arrow indicates

lammellar setae on tergite VI).

250

Figure 189: Psectrocladius sp. 2. Pupal thoracic horns

(arrow indicates thoracic horn).

Figure 190: Psectrocladius sp. 2. Pupal abominal tergites

and anal lobes (arrow indicates Pedes spurii 8).

252

Figure 191: Pseudosmittia sp. Pupal abdomen (arrow indicates

spinules on intersegmental conjunctive between

segments V and VI).

.

..

•

t,..

..

•

254

..c�

Q.Q)C...

Q)�

�.<'"'0C0

...,

0..

...,

N :Ee-...

G)..

::)CD «._

u. C'ICO

..,

0

-.

Eu

255

TA8LE 1: AIR AND WATER TEMPERATURES/FOR POND A

1983

DATE TIME AIR TEMP. WATER TEMP.

April 29 14:00 12 C 6 C

May 2 9:00 3 C 5 C

May 17 14: 00.

20 C 15 C

May 26 9:30 21 C 15 C

June 1 9:45 17 C 13 C

June 9 8:30 17 C 15 C

June 15 9:00 13 C 13 C

June 27 7:20 15 C 16 C

July 17 10:30 16 C 15 C

July 25 9:30 21 C 18 C

July 27 10:15 22 C 16 C

August 9 14:00 33 C 20 C

August 16 9:00 22 C 16 C

August 23 14:00 27 C 18 C

August 24 14:00 25 C 18 C

September 8 11 : 15 18 C 12 C

September 11 9:25 7 C 8 C

1984

April 6 9:45 7 C 2 CApril 18 13:30 20 C 7 C

256

TABLE 1: continued.

DATE TIME AIR TEMP. WATER TEMP.

May 9 9:00 12 C 7 C

May 21 10:00 30 C 9 C

June 10 17:00 19 C 14 C

July 1 12:00 21 C 17 C

July 15 16:00 25 C 18 C

July 22 10:30 18 C 17 - C

July 25 B:30 23 C 20 C

August 8 7:30 12 C 16 C

September 2 11 : 00 16 C 18 C

September 12 No Surface Water

September 19 11 : 30 2 C 8 C

257

TABLE 2: SPECIES LIST

* Species not collected from pond A.

TANYPODINAE

Ablabesm�ia (Karelia) Eulchripennis (Lundbeck)

Derotanypus alaskensis (Malloch)

Procladiu� (Psilotany�1) nietus Roback

Procladius (Holotanypus) sp.

Psectrotanypus £yari (Coquillet)

*Tanypus (Tanypus) punctipennis Meigin

CHIRONOMINAE

Tribe Chironomini

Chironomus atrella Townes

Chironomus !.!parius Meigen

Chironomu� (Camptochironomu1) tentans (Fabricus)Chironomus sp.

Cladopelma sp , 1

Cladopelma sp. 2

·Cryptochiron�� di9itatu� Malloch

Dicrotendipes sp.

Einfeldia sp.

Endochironomu� nigrican� (Johannsen)

Glyptotendipes barbipes (Staeger)

Glyptotendipes sp.

Parachironom� sp. 1

25B

TABLE 2: contiuned.

Parachironom� sp. 2

Parachiro·nomus sp. 3

*Phaenopsectra sp.

Tribe Tanytarsini

Cladotan;ltarsus sp.

Paratanytarsus sp.

Tan;ltarsus sp. 1I

Tanytarsus sp. 2

Tan;ltarsus sp. 3

ORTHOCLAOIINAE

Acricotopus senex (Johannsen)

Corynoneura sp. 1

Cor;lnoneura sp. 2

Cricotopus (Isocladiu�) ornatus (Meigen)

Cricotopus (Cricotopus) sp. 1

Cricotopus (Isocladiu�) sp. 2

*Hydrobaenus sp. 1

*Hydrobaenus sp. 2

Limnophyes sp.

Psectrocladius (Allopsectrocladius) flavus (Johannsen)

Psectrcocladius (Psectrocladius) sp. 1

Psectrocladius (Psectrocladiu�) sp. 2

Pseudosmittia sp.