Pinnularia Saprophila Guide
Credit: Marina Potapova
  1. Valves linear
  2. Apices capitate to slightly protracted
  3. Central area reaching the valve margin
  4. Striae radiate near the center

Valves are linear, with capitate to slightly protracted apices. Valves are 5.2-6.7 ┬Ám in width. The axial area is lanceolate, widening into a large central area that reaches the valve margins. Striae are often slightly bent, radiate near the valve center and extremely convergent at the apices.