Navicula Longicephala Guide
Credit: Marina Potapova
  1. Valves linear
  2. Valves 3.1-4.0 μm wide
  3. Valve apices rostrate to capitate
  4. Central striae strongly radiate
  5. Striae 18-21 in 10 μm

Valves are linear with rostrate to capitate apices. The raphe is straight, with close proximal ends. Striae are strongly radiate around the center, becoming convergent at the apices. The areolae are indistinguishable under LM.