Cymbopleura Tundraphila Guide
  1. Valve linear-lanceolate
  2. Valves small, < 5 µm wide
  3. Stria density 17-28 in 10 µm
  4. Proximal raphe ends simple, deflected ventrally
  5. Central area small, or lacking

Valves are small, linear-lanceolate and less than 5 µm wide. Striae are fine (17-28 in 10 µm) and radiate throughout. Proximal raphe ends are deflected ventrally and simple, rather than expanded or reverse-lateral. The central area is small or lacking.