Field Guide

Aquatic Invertebrates

Showing 1 - 7 of 7 results
Media
Photo of a northern, also called virile, crayfish.
Species Types
Scientific Name
Faxonius virilis (formerly Oronectes virilis)
Description
The virile crayfish is large, reddish brown or green, and lacks prominent markings. The pincers are green with orange tips and are studded with whitish knobs. Paired dark blotches run along the abdomen. This species is widespread.
Media
Photo of a water nymph crayfish, side view of specimen carefully arranged against black background
Species Types
Scientific Name
Faxonius nais (formerly Orconectes nais)
Description
The water nymph crayfish is normally found in streams but can also be found in a variety of other aquatic habitats. It is greenish brown or brown with no prominent markings. Its known distribution in Missouri is spotty.
Media
fatmucket
Species Types
Scientific Name
Lampsilis siliquoidea
Description
The fatmucket was a favorite species harvested for the button industry in the early 1900s.
Media
lilliput
Species Types
Scientific Name
Toxolasma parvus
Description
These diminutive mollusks are the smallest of Missouri’s freshwater mussels.
Media
white heelsplitter
Species Types
Scientific Name
Lasmigona complanata
Description
The shell of this mollusk is large and impressive in overall size. Although fairly flat, it can be more than 8 inches long. A large wing on the heelsplitter can be painful if you step on it.
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
Two pairs of Asian clam shells, still hinged together, showing exterior and interior
Species Types
Scientific Name
Corbicula fluminea
Description
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.