Key To Macroinvertebrate
s in Rivers and Streams
Shell Present
Shell Absent
Goto slide 2
Goto slide 3
1
ShellsSingle Shell
Double Shell
“Shell” with legs
Goto slide 7
Goto slide 8
Goto slide 11
2
No LegsWormlike
With tentacles, brushes or “tails”
Legs Present
Goto slide 4
Goto slide 9
Goto slide 10
Goto slide 12
Looks like a bunch of sticks or sand stuck
together
3
Legs Present Ten +
LegsThree Pairs of LegsElongated body, “extra appendages”
Goto slide 11
Goto slide 5
Goto slide 14
4
“Tail” filaments present
“Tail” filaments absentGoto slide 13
Goto slide 6
5
Two “Tail” filaments
Three “Tail” filaments
Goto slide 16
Goto slide 15
6
Snails
Group I Group III
7
Group IIClams & Mussels
8
Group IIILeeches
Group IIIOther Worms
Group IIIMidge Larvae
9
Group IICrane Fly, Horse Fly, Deer Fly LarvaeGroup IIIBlack Fly Larvae
10
CrustaceansGroup IICrayfish - Decapods
Group IIScuds or Side swimmers - Amphipods
Group IISowbugs - Isopods
11
Group I Group III12
Group IIGroup I
13
Group I Group II
14
Group I Group II
Other Beetle Larva
15
Group I Group II16
