Shell small to medium, ovate, sub-equilateral, roughly triangular; posterior side attenuated, dorsal acuminate, sculptured with fine concentric growth lines; ligament partially internal, hinge with two rows of tiny teeth, anterior with 18 teeth and longer posterior side with 20 teeth. Inside slightly nacreous with smooth margin, usually with pallial sinus. Periostracum thin, glossy. Colour: greenish to yellowish-brown. Size: average valve length, height and thickness