Solitary, more rarely observed in colonies. The cell is generally observed in girdle view and appears cylindrical with valves in the shape of cupolas. The frustule appears highly silicified. The edge of both valves can be undulating and they have two different types of spines. On the edge of one valve there are long sharp spines, T-shaped in cross section, with the upper part of the To flush with the edge of the valve. The other valve has two types of spines: one as described above and another crown of slightly shorter spines that terminate with barbs. In some cases, thin filaments like hairs also been observed, arranged in crowns. Distributed around the cell are numerous discoid chloroplasts.

Planktonic genus, typical of marine environments.

Report on the Diatomaceae collected by H.M.S. Challenger during the years 1873-76., Rept. Sci. Res. Voy. H.M.S. Challenger. Botany 2, Castracane F., 1886, 1-178