Valves are linear-elliptical with capitate to rostrate apices. Both raphe and rapheless valves have a lanceolate axial area and no distinct central area. Striae are radiate, parallel to slightly convergent at apices. The striae on raphe valve are interrupted by a thin longitudinal line in the middle of the valve, 22-26 in 10 µm. The striae on rapheless valve are slightly radiate, interrupted by a wide longitudinal hyaline area on each side of the valve, 18-20 in 10 µm.