Shape oval with slightly convex medial face and slightly concave lateral face. Dorsal depression shallow. Dorsal margin entire and ventral margin slightly serrate. Rounded at posterior margin. Sulcus ostial, deep. Ostium flared and cauda flared, bulbous posteriorly. Colliculum low. Collum raised tubercle. Crista superior well-developed. Crista inferior well-developed, poorly-developed at extremes. Neck dorso-ventrally constricted. Rostrum broad, rounded. Excisura wide. Notch deep, angle wide.