Pinnularia Microstauron Guide
Credit: Loren Bahls
  1. Valves linear
  2. Apices rostrate
  3. Fascia rhombic

Pinnularia microstauron has linear valves with rostrate apices. The central area is a rhombus, variously expanded into a narrow to wide fascia. Striae are radiate in the valve center, convergent near the apices, and number 9-11 in 10 µm.