Field Guide

The grassland crayfish is rather uniformly colored either bright red or reddish and has broad, powerful pincers. It inhabits prairies and grasslands from Wisconsin and Indiana to Texas, including grasslands in northern and western Missouri.

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.

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.

These small mussels use darters, a type of fish, as hosts for their young.

The fatmucket was a favorite species harvested for the button industry in the early 1900s.

A common mussel in some areas, deertoe have decorative green markings.

When a floater dies, this large mussel with a thick shell will actually rise to the water surface and float as it decays.

While the pimpleback is usually bumpy, some individuals are perfectly smooth.

The plain pocketbook is one of the most common and widespread mussels in our state. It is oval, relatively large, and occurs frequently.

Round pigtoes are more rounded than Wabash pigtoes. Usually, the nacre (the shell lining) is white, but in rare individuals it is bright pink.