Field Guide

Unlike their parasitic cousins in the flatworm group, turbellarians, or planarians, are tiny carnivores or detritus-eaters that glide smoothly across submerged leaves and other objects.

The belted crayfish is medium-small, tan, with a distinctive pattern of alternating olive-green and reddish-brown bands on the abdominal segments. It is found only in the Big River and its tributaries.

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 golden crayfish varies in color from olive green to golden yellow. Many body parts are trimmed with red. A dark band crosses the head just in front of the cervical groove, and another crosses the carapace at its junction with the abdomen. It's a wide-ranging species.

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 spothanded crayfish is moderately large and usually has a noticeable black spot on each pincer near the base of the movable finger. In Missouri, it is found mostly in Ozark waterways in the southeastern quarter of the state, from Callaway, Montgomery, and Warren counties south.

The coldwater crayfish has a very localized distribution in the Eleven Point River system. It is stout, with a blue-green head and pincers and dark, rust-brown carapace. It is an imperiled species.

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.