Shape pentagonal with postero-dorsal angle and flat medial face and flat lateral face. Dorsal depression very shallow. Dorsal margin and ventral margin very slightly crenate, lobed. Sulcus ostial, deep. Ostium flared, oval and cauda elongate, flexed ventrally at posterior. Colliculum low. Crista superior ridge-like and crista inferior well-developed, poorly-developed along ostium. Neck dorso-ventrally constricted. Rostrum very short. Excisura narrow. Notch deep, interrupted.