Field Guide

Aquatic Invertebrates

Showing 1 - 10 of 23 results
Media
Photo of backswimmer, side view
Species Types
Scientific Name
About 32 North American species in the family Notonectidae
Description
Sometimes called “water bees” or “water wasps,” backswimmers are predaceous and can deliver a painful bite if mishandled. True to their name, they swim belly-up, and their backs are keeled like a boat, which makes back-swimming easier.
Media
Photo of a giant water bug
Species Types
Scientific Name
Species in the genera Abedus, Belostoma, and Lethocerus
Description
Giant water bugs are huge aquatic insects that frequently fly around electric lights at night. They are infamous for the painful bite they can deliver, but fish, birds — and some people — find them tasty!
Media
Photo of a single water strider
Species Types
Scientific Name
Aquarius remigis; also species in the genus Gerris
Description
Water striders are hard not to notice. Water-repellant hairs on the hind and middle legs allow these nimble insects to skate on the surface of the water.
Media
Photo of a mayfly naiad crawling on rock underwater
Species Types
Scientific Name
There are hundreds of species in North America.
Description
Mayfly larvae, or nymphs, live from months to years under water, breathing through gills, and the adults fly around in the air, mating, living for only a day or two.
Media
Photo of a stonefly naiad clinging to a rock underwater
Species Types
Scientific Name
There are hundreds of species in North America
Description
Stonefly larvae are aquatic and somewhat resemble the larvae of mayflies and damselflies. Their presence usually indicates good water quality.
Media
Photo of hellgrammite
Species Types
Scientific Name
Corydalus cornutus
Description
Hellgrammites are the aquatic larval form of eastern dobsonflies. They are fiercely predaceous and look a little like centipedes. Anglers often use them as bait.
Media
Red midge fly larva, side view, in a petri dish
Species Types
Scientific Name
Nearly 1,100 species in North America
Description
Midge larvae look something like thin aquatic inchworms. They can be clear, whitish, olive, tan, or bright red. They occur in a variety of aquatic habitats. As adults, they resemble mosquitoes but they never bite.
Media
Water springtails congregate in water above soggy dead leaves
Species Types
Scientific Name
Podura aquatica
Description
In early spring, clusters of water springtails float on the surface of quiet waters, on muddy banks, and on protruding objects. Adults are bluish gray with reddish appendages.
Media
Photo of a water scorpion, genus Ranatra, captured in a jar of pond water.
Species Types
Scientific Name
Ranatra spp. and Nepa apiculata
Description
Water scorpions remain still, looking like a random bit of plant material. Then they suddenly grab their prey and deliver disabling fluids with a quick jab of their knifelike beak.
Media
Photo of two water penny beetles clinging to a wet rock.
Species Types
Scientific Name
Beetles in the family Psephenidae
Description
Water penny beetle larvae are truly nifty aquatic invertebrates that bring out the child in all of us. Some of them really do look like pennies!
See Also

About Aquatic Invertebrates in Missouri

Missouri's streams, lakes, and other aquatic habitats hold thousands of kinds of invertebrates — worms, freshwater mussels, snails, crayfish, insects, and other animals without backbones. These creatures are vital links in the aquatic food chain, and their presence and numbers tell us a lot about water quality.