Solitary or joined by small spines or granules of mucilage in colonies of varying length. Pairs or triplets of cells joined at the cingulum are distinctly observed. In girdle view the valves appear cylindrical. The valves are flat or swollen, and sometimes have a crown of large irregular spines. The intercalary bands may be numerous and narrow or completely absent. There are labiate processes, either along the edge of the mantle forming a ring of rimoportulae, or scattered or in groups on the valve surface. Along the cell wall there are numerous circular chloroplasts.

Freshwater and marine environments.

AlgaeBase. World-wide electronic publication, National University of Ireland, Galway., http://www.algaebase.org, Guiry M.D., Guiry G.M., 2011,

Checklist of Baltic Sea Phytoplankton Species. Baltic Sea Environment Proceedings No. 95, Helsinki Commission Baltic Marine Environment Protection Commission, Hällfors G., 2004,