The spiny softshell can be distinguished from the smooth softshell by the presence of two yellow, black-bordered lines along each side of the head, a row of spines along the front edge of the carapace, and a raised nasal septum, giving the nostrils a "C" shape. Young and males have olive-gray carapaces with small black markings often appearing like thin donuts. Adult females have dark olive or tan carapaces with brown and gray mottling.