Shape elliptic with raised dorsal angle in the middle and convex medial face and concave lateral face. Dorsal depression shallow. Dorsal margin crenate and ventral margin slightly serrate. Sulcus ostial, deep. Ostium reduced, triangular, fringing rostrum. Cauda elongate, directing ventrally then markedly flexed ventrally at posterior tip. Colliculum low. Crista superior ridge-like before caudal flexion and well-developed posteriorly. Crista inferior well-developed. Neck dorso-ventrally constricted. Rostrum large, rounded. Excisura wide. Notch deep, angle wide.