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Guide to Ulnaria goulardii

(Bréb. ex Cleve and Grunow) D.M.Williams, Potapova and C.E.Wetzel 2020

Synedra Goulardii Guide
Credit: Ian Bishop
  1. Mid-valve constriction
  2. Two rimoportula per valve
  3. "Ghost" striae in central area
  4. Parallel striae, becoming radiate at ends
  5. Shortened, interrupted striae bordering central area

Valves are distinctly constricted at mid-valve. Striae are parallel, becoming slightly radiate at the apices. "Ghost" striae may be present in the central area. Each valve has two rimoportula, one at either end, near the apices.