Cymbella Fontinalis Guide
  1. Valves weakly dorsiventral
  2. Ventral margin slightly convex to nearly flat
  3. Proximal raphe ends reverse-lateral
  4. Stigmata distinct, separated from ends of striae
  5. Striae radiate throughout

Valves are weakly dorsiventral with acutely rounded, unprotracted apices. The ventral margin is slightly convex to nearly flat. Striae are radiate throughout. Stigmata are distinct and separated at some distance from the ends of the median ventral striae. Proximal raphe ends are reverse-lateral and terminate in tear-shaped pores.