It has a triangular-shaped head with a somewhat hooked beak with large crushing surfaces.
Hatchlings are black on both sides.
As the turtle matures, the bridge and hingeless plastron change to white then yellow, and the carapace to gray then olive green. The head and paddle-like limbs are gray. Adults weigh between 77 and 93 pounds and have a carapace length of 22 to 28 inches. Close examination of the carapace reveals five pairs of pleural shields with the nuchal shield touching the first costals. There are 12 to 14 marginals on each side to the carapace, and pores in the four bridge infra-marginal scutes.