Key to Life in the PondNo ShellsShells

Double ShellSingle Shell Without Backbone (Invertebrates)With Backbone (Vertebrates)

External gills(legs may not be present)

No gills

SalamanderLarva Tadpole

Fish

No Legs

Worm-LikeWith Tentacles, Brushes or “Tails”

body with bristles,no suckers

reddish brown,segmented body

glides alongbottom, body not

segmented

suckers, expandsand contracts,

segmented body

small, hair-like,swims in

“S”-shape

tan to brown,long

BristleWorm

TubifexWorm

Leech

Nematode orThreadworm

Flatworm orPlanaria

on surface, stif fwith tail disk

breathing tubeat rear

red, green ortan 'twists',distinct head

large head,'wriggles'

transparentbody

Soldier FlyLarva

MosquitoLarva

MosquitoPupa

Phantom MidgeLarva

Midge Larva

HorsehairWorm

Microscopic

tentaclesswims witha jerk – using

antennas

apostrophe-shaped

round

HydraCyclops orCopepod

Seed & ClamShrimp

Water Fleaor

Daphnia

spiral,opening on lef t

small,whitish, tan or brown

spiral,opening on right

Pouch Snail Gilled Snail

Pill orFingernail

Clam

coiled

Orb Snail

large, 2 to 8 inches,dark-colored

FreshwaterMussel

lobster-like pinkish,feathery

shrimp-like,swims on side

walks onbottom

Crayfish

FairyShrimp

Scud orAmphipod

AquaticSowbug or

Isopod

Fewer than Three “Tails”

large mouth parts,“spines” on side

large body,hinged mouth

of ten lives intube or case

hangs from surface,large mouth parts

tiny, hopson surface

DobsonflyLarva

DragonflyLarva Predaceous

Diving BeetleLarva

Springtail

Caddisflylarva

Three “Tails”

plate-like “tails,”no gills on abdomen

long “tails,”gills on

abdomen

DamselflyLarva

MayflyLarva

Beetle-Like, Wings Hard

swims, moving hindlegs alternating

back legs moveat same time

swims onsurface

“crawls” throughwater, spotted

WaterScavenger

Beetle

PredaceousDivingBeetle

WhirligigBeetle

CrawlingWaterBeetle

Legs

10+ Legs Four Pairs of Legs Three Pairs of Legs

tiny, of ten brightlycolored

runs on topof water

Water Mite

Fishing Spider

Leathery Wings (True Bugs)

swims on back,back white

dark, lives onsurface

long,stick-like

tan, lives onsurface

swims right-sideup, back black

BackswimmerWaterStrider

MarshTreader

WaterBoatman

Water Scorpion‘Ranatra’

long breathing tube,grasping front legs

WaterScorpion‘Nepa’

grasping front legs,up to three inches

GiantWater Bug

Wings

No Wings

PyralidCaterpillar

six legs andprolegs onabdomen

(Sizes of illustrations are not proportional.)

side viewof “tails”

Developed by the University of Wisconsin–Extension in cooperation with the WisconsinDepartment of Natural Resources. Based on akey developed by Riveredge Nature Center, Newburg, WI. May be reproduced with thiscredit for educational, non-profit purposes. For information, contact UWEX EnvironmentalResources Center, 608/262-2634. Universityof Wisconsin-Extension is an EEO/AffirmativeAction employer and provides equal opportuni-ties in employment and programming, includingTitle IX and ADA requirements.