Geissleria Kreigeri Guide Copy
Credit: Marina Potapova
  1. Valves elliptical-lanceolate with subrostrate apices
  2. Central area small
  3. Areolae in central area absent
  4. 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.