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Guide to Eunotia orthohedra

Furey, Lowe and Johansen 2011

Eunotia Orthohedra Guide
Credit: Paula Furey
  1. Ventral margin with subapical swellings
  2. Dorsal margin straight
  3. Angular shoulders subtending the apices
  4. Apices capitate, dorsally recurved
  5. Striae indistinct, radiate

The ventral margin is slightly concave with subapical swellings at the proximal raphe ends. The dorsal margin is flattened with angular shoulders subtending the apices. Valves are narrow and 4.2 – 6.0 times longer than wide. The apices are capitate, dorsally recurved and rounded. The raphe is short and curves on to the valve face. The striae are radiate and may be faint in appearance.