This adult female river cooter is a captive individual. The muted colors of the carapacial design are not usually visible in wild specimens as they would be obscured by mud and algae. Photo by Mary Hopson, used with permission. The carapace is rather flat, not highly domed. The second pleural scute has a characteristic C-shaped mark.
Hatchlings have a central keel which disappears with age.
The skin is olive to brown, with yellow stripes. The plastral pattern tends to fade with age. Males have a broader tail and may have a slightly concave plastron. Females tend to grow larger than males. The stripe down the outside of the hind foot is an identifying characteristic.