White River Crayfish-Procambarus acutus (Girard)

Adults of this species are usually a deep burgundy red with a black V-shaped stripe on the abdomen. Juveniles are gray with dark spots scattered over the carapace. The pincers are long and narrow. The carapace is separated at its middle by a space (areola). The carapace is conspicuously granular (roughened) in adults. Adults are about 2.6 to 4.1 inches in length.

This crayfish occurs commonly in the Lowlands of southeastern Missouri, and northward along the floodplain of the Mississippi River to Clark County. It inhabits sloughs, swamps and sluggish lowland streams and ditches. It frequently burrows to escape drying or freezing.

The White River crayfish resembles the red swamp crayfish. The latter species differs most notably in lacking an areola. Young of the red swamp crayfish are usually plain or striped, not spotted.

Article Source: http://mdc.mo.gov/nathis/arthopo/crayfish/varcraw.htm