Author(s): Laurent Dabouineau, Alain Ponsero
Anatomy of the shell - The two valves are quite si milar, but inequilateral. Broadly oval, up to 50mm long. Shell with 22 to 28 conspicuous broad ribs, closely spaced. External ligament, rubbery appearance, that is tends to open shell permanently . Two adductor muscle scars (these mu scles serve to close the shell) . Pallial line without sinus.