Field Guide

Aquatic Invertebrates

Showing 1 - 10 of 22 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 whirligig beetle viewed from above
Species Types
Scientific Name
Species in the beetle family Gyrinidae
Description
Groups of whirligig beetles swim on the water surface in quick, random patterns, searching for food. They have two pairs of eyes — one pair above water, one pair below — to help them quickly and accurately capture their prey.
Media
Photo of a predaceous diving beetle
Species Types
Scientific Name
Species in the beetle family Dytiscidae
Description
Like many aquatic insects, these large oval beetles prey voraciously on other aquatic organisms. Excellent swimmers, they fly well, too, and are often attracted to lights.
Media
Photo of a collared water scavenger beetle showing back.
Species Types
Scientific Name
Beetles in the family Hydrophilidae
Description
Water scavenger beetles are a mostly aquatic family. They are similar to predaceous diving beetles, but unlike them many have a distinctive spine running down the center of their bellies.
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
Water boatman viewed from above
Species Types
Scientific Name
About 125 species in North America in the family Corixidae
Description
Water boatmen are one of the few aquatic true bugs that are not predatory and do not bite people. Instead, they suck juices from algae and detritus. Only a few types eat other small aquatic creatures.
Media
Photo of a dragonfly larva resting on a stone.
Species Types
Scientific Name
Species in the suborder Anisoptera
Description
Dragonfly larvae are aquatic insects with large eyes, six legs, and an oval or rounded segmented abdomen. The lower jaws are scooplike and cover much of the lower part of the head.
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 crane fly larva
Species Types
Scientific Name
There are over 500 species of crane flies in North America.
Description
Crane fly larvae are tan or gray grubs that live in aquatic habitats or in moist places on the ground. The harmless adults resemble huge mosquitoes.
Media
Photo of a fishfly larva crawling among rocks in an aquarium.
Species Types
Scientific Name
Chauliodes, Neohermes, and Nigronia spp. (in eastern US)
Description
Fishfly larvae look a lot like their cousins the hellgrammites, but they lack cottony or hairy gill tufts along the abdomen, and they have 2 short, fleshy tails at the hind tip.
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.