Raeta plicatella (Lamarck, 1818) - Channeled Duck Clam.

Up to 7.5 cm long, inequilateral (beaks posterior to midline), broad anteriorly but more pointed and gaping posteriorly. White, yellow-brown or grey in color and extremely fragile. The external surface is sculptured by distinct, smooth, concentric ridges and grooves which are more numerous and closer inside of the valves. The left valve bears 3 cardinal teeth (2 of which form the characteristic V-shape and the 3^rd which is weak and often broken), 1 anterior and 1 posterior lateral. The right valve bears 2 cardinal teeth and 1 posterior lateral tooth but the anterior one appears to be absent. There is again a prominent chondrophore separated from the external ligament by a thin plate or spetum. Pallial sinus fairly well developed. Red-brown periostracum.