Stauroneis Anceps Guide
Credit: Loren Bahls
  1. Apices protracted and narrowly rostrate
  2. Valves lanceolate to linear-lanceolate
  3. Stauros narrow and rectangular

Valves are moderately large, lanceolate to linear-lanceolate and 12-15 ┬Ám wide. The apices are distinctly protracted, narrow and rostrate. The stauros (in specimens from the Northern Rockies) is relatively narrow and rectangular. Proximal raphe ends are weakly expanded and deflected.