Field Guide

Aquatic Invertebrates

Showing 1 - 10 of 21 results
Media
Bluefer
Species Types
Scientific Name
Potamilus purpuratus
Description
Like the pink heelsplitter and fragile and pink papershells, the bluefer uses freshwater drum as a host.
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 papershell crayfish, also called calico crayfish.
Species Types
Scientific Name
Faxonius immunis (formerly Orconectes immunis)
Description
The calico crayfish is rather plain: gray-green with a pale central zone along the middle of the carapace and abdomen. The pincers are orange-tipped, and in mature males are tinged with purple. It is usually only found in the northern half of the state.
Media
Photo of a spothanded crayfish viewed from above on white background.
Species Types
Scientific Name
About 36 species in Missouri
Description
Crayfish are freshwater aquatic invertebrates that look a lot like small lobsters, to which they are related. There are about 36 species of crayfish in Missouri.
Media
Photo of a devil crayfish.
Species Types
Scientific Name
Lacunicambarus aff. diogenes (syn. Cambarus diogenes)
Description
The powerfully built devil crayfish is usually a uniform olive or tan, without obvious blotches or spots. It digs underground burrows, often with mud chimneys, and has a wide distribution.
Media
Photo of a digger crayfish.
Species Types
Scientific Name
Creaserinus fodiens (formerly Fallicambarus fodiens)
Description
The digger crayfish is heavy-bodied, reddish tan, with a pale, iridescent stripe along the midline of the abdomen and short, broad pincers. In Missouri, it is known from only a few locations, mostly in southeastern counties.
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.
Media
pond mussel
Species Types
Scientific Name
Bivalve molluscs in order Unionoida
Description
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.
Media
Photo of a horsehair worm in an aquarium
Species Types
Scientific Name
About 350 species scientifically described.
Description
Adult horsehair worms can be nearly 3 feet long and live in water. They are practically featureless, smooth, aquatic worms that writhe into knots and curls.
Media
Photo of a leech
Species Types
Scientific Name
Various species in the subclass Hirudinea
Description
Who isn't repulsed by leeches! Yet once you get past the fact that many species are parasitic bloodsuckers, you will discover that they are fascinating creatures.
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.