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Guide to Eunotia lewisii

Siver and Hamilton 2009

Eunotia Lewisii Guide
Credit: Jen Beals
  1. Ventral margin depressed between proximal raphe ends
  2. Stria density consistent
  3. Striae radiate distal to the terminal raphe ends
  4. Terminal raphe ends cross the valve face near the apices
  5. Helictoglossae prominent

The ventral margin is depressed between the proximal raphe ends; the dorsal margin is flat and parallel to the ventral margin. Apices are rostrate. Striae are evenly spaced and parallel, becoming radiate distal to the terminal raphe ends. The raphe curves across the valve face at the apices, with a prominent helictoglossa and a thickened ridge running from the helictoglossa to the dorsal margin.