Elliptic to oval in shape with convex medial face and concave lateral face, especially anterior part. Dorsal margin entire and ventral margin serrate. Sulcus ostial, shallow to moderately deep. Ostium flared, deeper than cauda. Cauda bulbous. Crista superior and crista inferior well-developed. Neck dorso-ventrally constricted. Rostrum extended and blunt. Antirostrum small. Excisura narrow. Notch shallow.