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Guide to Halamphora normanii

(Rabenh.) Levkov 2009

Halmphora Normanii Guide
Credit: Josh Stepanek
  1. Proximal raphe ends sharply deflected
  2. Dorsal fascia with siliceous thickening
  3. Ventral striae continuous

Valve apices are protracted, capitate, and ventrally curved. The raphe is located near the valve midline, with sharply deflected proximal ends. The axial area is narrow on the dorsal side and extends nearly to the valve margin on the ventral side. A fascia present on the dorsal side forming a thickened semi-stauros, ventral fascia absent. Dorsal striae interrupted longitudinally, ventral striae composed of a single row of very short areolae along the entire ventral margin.