Navicula Cryptocephala Guide
Credit: Marina Potapova
  1. Valves lanceolate with protracted apices
  2. Central area large, circular
  3. External proximal raphe ends expanded

Valves are lanceolate with protracted apices The central area is large and circular. The raphe is straight, with 'drop-like' expanded external proximal ends. Striae are radiate around the center, becoming convergent at the apices. The areolae are sometimes visible under LM, approximately 35 in 10 μm.