Shape oval to pentagonal with raised dorsal angle in the middle and postero-dorsal angle. Convex medial face and concave lateral face. Dorsal depression shallow. Dorsal margin entire and ventral margin serrate, dentate. Sulcus ostial, deep. Ostium flared, 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 extended, rounded. Excisura wide. Notch shallow.
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