Eunotia Bidens Guide
Credit: David Burge
  1. Dorsal undulations broad
  2. Weakly arcuate valves
  3. Transapical striae nearly parallel
  4. Apices subcapitate
  5. Ventral undulations small

Valves are dorsi-ventral, with weakly curved with biundulate dorsal margins. Dorsal undulations are broad, where as ventral undulations are small and narrow. Striae are coarse, becoming denser near the ends. Apices are subcapitate with obtusely rounded ends. Small ventral undulations coincide with proximal raphe endings.