No picture so far.
Cells and setae contain many small chloroplasts. The cells are hetrovalvate (upper valve rounded; lower valve flattened). The chains are sometimes twisted around the pervalvar axis and the setae curved towards the lower part of the chain. The girdle zone is more than 1/3 of the length of the pervalvar axis. The windows are small and almost covered by the setae that are of equal width from the base and outwards. The lower valve of the terminal cell may have only one seta.
Apical axis measures 10-27 um.
Throndsen, J., Hasle, G.R. and Tangen, K., 2007. Phytoplankton of Norwegian coastal waters. Almater Forlag AS. 341 pp.