Shell thick with a variable, moderately inflated shape, elongate-ovate to subquadrate in outline, relatively long for its height. Umbones markedly anterior to the midline. Lunule long, narrow and about 3 to 4 times longer than wide. Escutcheon on both valves well marked, deep and narrow. Outer sculpture with finely latticed concentric and radial ribs. Hinge with 3 cardinal teeth, without the lateral teeth. Pallial sinus shallow, well developed, but far from attaining the midlength of the valves. Internal margins smooth. Colour: variable, cream to fawn, brown or grey, variegated or uniform.