Fusiform, elongate in shape with convex medial face and concave lateral face. Dorsal depression shallow, fan-shaped. Dorsal margin and ventral margin serrate. Sulcus ostial, deep. Ostium flared and cauda elongate, flexed at posterior. Colliculum high in the middle of sulcus. Crista superior and crista inferior well-developed. Neck dorso-ventrally constricted. Rostrum extended, pointed, downward. Excisura wide. Notch deep with wide angle.