Gomphonema Coronatum Guide
Credit: Pat Kociolek
  1. Valves acuminate-apiculate
  2. Length 34-108 ┬Ám
  3. Widely tumid central portion

Valves are acuminate-apiculate, with a small, acute to blunt protracted headpole. The broadest portion of the valve is at the headpole and/or the central portion of the valve. On one side of the central area there is a shortened stria, on the opposite side the central stria terminates at the stigma.