Shell oval-modioliform, stout, beaks subterminal. Ventral margin almost straight to slightly concave. Postero-dorsal margin somewhat convex. Ligament plate slightly arched. Exterior with dense fine commarginal lines. Periostracum smooth and glossy, strong, dark brown to blackish brown, in young specimens chestnut brown. Anterior retractor scar at anterior extremity of the umbonal cavity. Anterior part of posterior byssus retractor muscle scar at 2/3 the ligament length. Animal with large gills. Inner mantle folds separate along the whole ventral margin. Valvular siphonal membrane short, narrow and rather strong.
HASHIMOTO J. (2001) Venus 60(3): 141-149.