Field Guide

Aquatic Invertebrates

Showing 51 - 60 of 92 results
Media
Photo of a ramshorn snail on a wet rock.
Species Types
Scientific Name
Gyraulus, Helisoma, Menetus, Micromenetus, Planorbula spp.
Description
Ramshorn snails are easy to identify at a glance, because the shell is a flat, disklike coil. Like other pulmonate aquatic snails, they lack the hard horny “trapdoor” possessed by other types of aquatic snails.
Media
Photo of a Neosho midget crayfish.
Species Types
Scientific Name
Faxonius macrus (formerly Orconectes macrus)
Description
The Neosho midget crayfish is a subdued mottled brown, with a prominent black band crossing the carapace near its junction with the abdomen. The pincers are broad and powerful. This small, stout crayfish is found in the Neosho stream drainage of southwestern Missouri and northwestern Arkansas.
Media
Photo of Williams' crayfish.
Species Types
Scientific Name
Faxonius williamsi (formerly Orconectes williamsi)
Description
Williams' crayfish is small and rather plain, without bright colors or bold markings. It has a pale, vase-shaped zone along the middle of the dark olive-tan carapace. It is found only in the upper White River drainage of Missouri and Arkansas.
Media
Meek's Crayfish
Species Types
Scientific Name
Faxonius meeki (formerly Orconectes meeki)
Description
The pincers of Meek's crayfish are sprinkled with many blackish spots. There is a dark spot near the tubercle at the base of the moveable finger. In Missouri, this rare crayfish occurs in only a few tributaries of Table Rock Lake in Stone County.
Media
Photograph of Ebonyshell freshwater mussel shell exterior view
Species Types
Scientific Name
Fusconaia ebena
Description
At one time the most valuable shell to the commercial button industry, the ebonyshell is now classified as endangered in Missouri and is a candidate for federal endangered status.
Media
Photograph of Purple Wartyback freshwater mussel shell exterior view
Species Types
Scientific Name
Cyclonaias tuberculata
Description
Before buttons were made of plastic, they were made of shell. Because only white buttons were in demand, the coppery-purple shell of this species made it worthless for the button industry.
Media
Photograph of Sheepnose freshwater mussel shell exterior view
Species Types
Scientific Name
Plethobasus cyphyus
Description
The sheepnose has been classified as endangered in Missouri and is a candidate for federal endangered status.
Media
elktoe
Species Types
Scientific Name
Alasmidonta marginata
Description
The elktoe is one of many Missouri mussels with a declining population.
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?
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.