(Krasske) Lange-Bert. in Lange-Bert. and Metzeltin 1996
Credit: Marina Potapova
Valves elliptical-lanceolate with subrostrate apices
Central area small
Areolae in central area absent
Annulae in three or four rows at poles
Valves are elliptical-lanceolate with subrostrate ends, 5.0-7.5 µm wide and 11-23 µm long. The central area is small, without isolated areolae. Striae are uniseriate, radiate, and number 16-23 in 10 µm. The annulae form three-four rows at each pole.