Solitary. In valve view the cells have a discoid shape, while in girdle view they appear rectangular. The valves are divided into a maximum of 20 sectors, which are alternatively raised and depressed, while the central area is smooth or granular. On the outer edge of the raised areas there are prominent rimoportulae, with curved or square internal apertures. Areolae arranged in radial striae can also be seen. The valve mantle often has spines or siliceous excrescences similar to verrucas. In contrast the edge is smooth. The cell contains numerous chloroplasts.

Common, benthic.

Verbreitung und einfluss des mikroskopischen lebens in Süd- und Nord-Amerika., Akad. Wiss. Berlin, Ehrenberg C.G., 1843, 291-466, Pls 1-4