Red Swamp Crayfish-Procambarus clakii (Girard)

Adults of this species are colored dark red (nearly black on the carapace), and have a wedge-shaped black stripe on the abdomen. Juveniles are a uniform gray, sometimes overlain by dark wavy lines. The pincers are narrow and long. The carapace is not separated at the middle by a space (areola). The carapace is conspicuously granular (roughened) in adults. The rostrum has lateral spines or notches near its tip. Adults are about 2.2 to 4.7 inches in length.

The red swamp crayfish is the most abundant large crayfish in many swamps, sloughs and sluggish ditches of the Lowlands. It generally avoids streams and ditches with strong flow, where it is replaced by the White River crayfish. The red swamp crayfish burrows during periods of drought or cold.

This crayfish most closely resembles the White River crayfish, which differs most obviously in having an areola. Young of the White River crayfish usually have spots on the carapace.

Article Source:

http://mdc.mo.gov/nathis/arthopo/crayfish/varcraw.htm#anchor1223529