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Guide to Achnanthes coarctata

(Bréb. ex W.Sm.) Grunow in Cleve and Grunow 1880

Achnanthes Coarctata Guide
Credit: Sarah Spaulding
  1. Valve margin biundulate
  2. Raphe valve with central fascia
  3. Areolae distinct
  4. Rapheless valve with eccentric axial area

Valves have biundulate margins, with a central constriction. The raphe valve face has a broad, central fascia. The fascia maybe asymmetric. The rapheless valve has a narrow, eccentric axial area. Striae are uniseriate and distinctly punctate.