Field Guide

Aquatic Invertebrates

Showing 1 - 7 of 7 results
giant floater
Giant Floater
Pygandon grandis
When a floater dies, this large mussel with a thick shell will actually rise to the water surface and float as it decays.
pond mussel
Freshwater Mussels
Bivalve molluscs in order Unionoida
Secretive and seldom seen, freshwater mussels are extraordinarily diverse in Missouri. We have nearly 70 species within our borders. Many are declining, and several are endangered.
Photo of a collared water scavenger beetle showing back.
Water Scavenger Beetles
Beetles in the family Hydrophilidae
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.
Water boatman viewed from above
Water Boatmen
About 125 species in North America in the family Corixidae
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.
Photo of a spotted fishing spider perched on the water's surface amid floating duckweed plants
Aquatic Spiders
Dolomedes spp., Tetragnatha spp., and others
A variety of spiders are adapted for live on and around water. Many of these are called fishing spiders. Several have the ability to run across the water’s surface. Some build webs, others do not.
Photo of a single water strider
Water Striders
Aquarius remigis; also species in the genus Gerris
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.
Two pairs of Asian clam shells, still hinged together, showing exterior and interior
Asian Clam
Corbicula fluminea
The Asian clam is a nonnative, invasive species that lives in a variety of aquatic habitats. It has thick shells with distinctly ridged, concentric rings and a yellowish-brown to dark brown shell covering.
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.