Key to Life in the Pond
(Sizes of illustrations are not proportional.)
No Shells
Shells
Double Shell
Single Shell
spiral,
opening on left
coiled
spiral,
opening on right
With Backbone (Vertebrates)
Without Backbone (Invertebrates)
No gills
External gills
(legs may not be present)
large, 2 to 8 inches,
small,
dark-colored
whitish, tan or brown
No Legs
Fish
Pouch Snail
Pill or
Fingernail
Clam
Orb Snail
Gilled Snail
Salamander
Larva
Freshwater
Mussel
With Tentacles, Brushes or “Tails”
breathing tube
at rear
large head,
'wriggles'
Legs
Mosquito
Pupa
Mosquito
Larva
transparent
body
Worm-Like
on surface, stiff
with tail disk
body with bristles, reddish brown, suckers, expands small, hair-like,
segmented body and contracts,
swims in
no suckers
segmented body
“S”-shape
red, green or
tan 'twists',
distinct head
Midge Larva
Phantom Midge
Larva
Bristle
Worm
Nematode or
Threadworm
Tubifex
Worm
Soldier Fly
Larva
Leech
round
10+ Legs
lobster-like
pinkish,
feathery
Four Pairs of Legs
shrimp-like,
swims on side
walks on
bottom
tiny, often brightly
colored
runs on top
of water
swims right-side
up, back black
swims on back,
back white
dark, lives on
surface
Horsehair
Worm
Flatworm or
Planaria
Microscopic
tentacles
swims with
a jerk – using
antennas
Hydra
Cyclops or
Copepod
tan, lives on
surface
tan to brown,
long
Seed & Clam
Shrimp
Wings
Leathery Wings (True Bugs)
Fishing Spider
Scud or
Amphipod
Fairy
Shrimp
glides along
bottom, body not
segmented
apostropheshaped
Three Pairs of Legs
Water Mite
Tadpole
long,
stick-like
long breathing tube,
grasping front legs
Water Flea
or
Daphnia
grasping front legs,
up to three inches
Aquatic
Sowbug or
Isopod
Water
Boatman
Crayfish
Backswimmer
Water
Strider
Marsh
Treader
Giant
Water Bug
Beetle-Like, Wings Hard
No Wings
Fewer than Three “Tails”
six legs and
prolegs on
abdomen
Developed by the University of Wisconsin–
Extension in cooperation with the Wisconsin
Department of Natural Resources. Based on a
key developed by Riveredge Nature Center,
Newburg, WI. May be reproduced with this
credit for educational, non-profit purposes.
For information, contact UWEX Environmental
Resources Center, 608/262-2634. University
of Wisconsin-Extension is an EEO/Affirmative
Action employer and provides equal opportunities in employment and programming, including
Title IX and ADA requirements.
large mouth parts,
“spines” on side
large body, hangs from surface,
hinged mouth large mouth parts
Water
Scorpion
‘Nepa’
Three “Tails”
tiny, hops
on surface
often lives in
tube or case
plate-like “tails,”
no gills on abdomen
long “tails,”
gills on
abdomen
Water Scorpion
‘Ranatra’
swims, moving hind
legs alternating
back legs move
at same time
swims on
surface
“crawls” through
water, spotted
Whirligig
Beetle
Crawling
Water
Beetle
Springtail
Pyralid
Caterpillar
Dobsonfly
Larva
Dragonfly
Larva
side view
of “tails”
Predaceous
Diving Beetle
Larva
Caddisfly
larva
Damselfly
Larva
Mayfly
Larva
Water
Scavenger
Beetle
Predaceous
Diving
Beetle