The frustles in the girdle view are rectangular. The ventral margin is straight at the ends, concave toward the center of the valve. The dorsal margin is convex with from four to twenty undulations. Length of the valve varies with the number of undulations. The apices of the valve are rounded and not distinctly differentiated from the main body of the valve. The terminal nodules are distinct, on the ventral margin, a short distance from the apices of the valve. Striae are distinctly or indistinctly punctae. Striae are parallel and radiate over the terminal modules(Patrick and Reimer 1966).