Field Guide

Aquatic Invertebrates

Showing 11 - 20 of 35 results
Media
Photo of a gravid Mississippi grass shrimp in an aquarium.
Species Types
Scientific Name
Palaemonetes kadiakensis
Description
Of Missouri’s two species of freshwater shrimp, the Mississippi grass shrimp is by far the most common and widespread.
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.
Species Types
Scientific Name
Various species in the genus Hydra
Description
We’ve all seen aquariums and pictures of tropical saltwater invertebrates such as corals, jellyfish and anemones—but did you know that there are similar creatures living in the freshwater habitats of Missouri?
Media
Photo of a leech
Species Types
Scientific Name
Various species in the subclass Hirudinea
Description
Most people are repulsed by leeches. But once you get past the fact that many species are parasitic bloodsuckers, you will discover that they are fascinating creatures with an important role in nature.
Media
Photo of a freshwater jellyfish
Species Types
Scientific Name
Craspedacusta sowerbii (syn. C. sowerbyi)
Description
You may have heard about stinging jellyfish in the ocean, but did you know that there are similar creatures living in the freshwater of Missouri? Fortunately, they’re harmless!
Media
Gray, speckled, translucent gelatinous blob cut in half to show structure
Species Types
Scientific Name
Freshwater species in the phylum Bryozoa
Description
Bryozoans are tiny, filter-feeding invertebrates. They create colonies that can be mossy, branching, or round and jellylike.
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!
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.