Field Guide

The woodland crayfish is stout, reddish tan to dark brown, with numerous blackish specks and blotches on the pincers, carapace, and abdomen. It occurs only in Missouri, especially in the Black River and its tributaries.

The Ozark crayfish is light brown to reddish brown with numerous black specks on the pincers and often on the abdomen as well. The pincers are broad and powerful. It lives in the White and Black stream systems.

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.

The saddleback crayfish has a bold blackish band across the hind margin of the carapace and lacks dark blotches or specks. The pincers are broad and powerful. It occurs in the Big and Meramec river drainages.

The ringed crayfish is olive green to reddish tan and usually has black or brown rings around the pincer tips. In Missouri it is found in clear, rocky Ozark streams in the southwestern quarter.

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.

Often overlooked by people, but eagerly sought by fish, Missouri’s amphipods resemble shrimplike sowbugs. Scuds live in various aquatic habitats, and several species inhabit caves.

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.

The Arkansas brokenray only occurs in streams that flow south off of the Salem and Springfield plateaus, so it is found only in about the southern quarter of Missouri.