Medium-sized (up to 15 cm CL) turtle with dark olive, dark brown, or black carapace and lighter plastron. Vertebral scutes 1-4 mushroom-shaped, broadest anteriorly. Male averages larger than female, with divided patch of rough scales behind knee and longer, heavier tail tipped with a claw. Young with prominent black dot on posterior part of large carapacial scutes and ninth marginal scute higher than eighth.