DESCRIPTION: A large (shell up to 470 mm or 18.5″ in length), exceptionally flat, disc-shaped water turtle with a leathery shell and a pointed, snorkel-like snout. Soft, fleshy lips conceal a large, sharp jaw. The leading edge of the shell is adorned with small tubercles. Overall coloration is tan, gray, or olive and the top part of the shell (carapace) is often marked with spots or ocelli. A thin, dark line runs around the margin of the light-edged carapace. Shell markings are more distinct on juveniles and males. The head and limbs are often marked with small, black flecks or speckles. The bottom part of the shell (plastron) is cream or white and is partially translucent. The limbs are flat and paddle-like and the feet are webbed. Females grow to a much larger size than males. Males have a sand-paper like texture on the carapace.

HABITAT: Occurs in rivers, canals, urban lakes, ponds, reservoirs, and irrigation ditches within Arizona’s desertscrubs and Semidesert Grassland communities. Seems to prefer relatively quiet, shallow waters with gradual banks and soft soil.

BEHAVIOR: A highly aquatic turtle that rarely travels overland. It basks on the bank, on floating logs, or by floating in sunlit surface water. It also thermoregulates by burying itself in the soil beneath shallow, sun-warmed water and using its long neck and snorkel-like snout to reach the surface for air. It is able to extract oxygen from the water through the blood vessel rich linings of its pharynx and cloaca. This enables the turtle to stay underwater for long periods of time. It is capable of striking quickly and can deliver a painful bite.

DIET: Primarily carnivorous but occasionally eats plant material. Prey items include crayfish, fish, amphibians, reptiles, worms, and snails. Also feeds on carrion.