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Guide to Didymosphenia geminata

(Lyngb.) M.Schmidt 1899

Didymosphenia Geminata Guide
Credit: Sarah Spaulding
  1. Valves large
  2. Headpole capitate
  3. Stigmata 2-5
  4. Apical porefield present
  5. Distal raphe deflected

The valves are large and robust. The headpole is distinctly capitate, while the footpole may be capitate or not. The number of stigmata is variable, but depends on valve size. A porefield is present at the footpole. The distal raphe is deflected at the footpole, rather than bisecting it.