Diatoms of North AmericaDiatoms of North America
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Guide to Capartogramma

Kufferath 1956

Capartogramma Crucicula Guide
Credit: Marina Potapova
  1. Central region X-shaped
  2. Pseudosepta present
  3. Axial area narrow
  4. Striae uniseriate, punctate

Capartogramma is characterized by a very distinctive "x-shaped" thickening of silica near the central part of the valve. Frustules are generally lanceolate in valve outline. Pseudosepta are present at the valve apices. The raphe is positioned within a narrow axial area. Striae are uniseriate and punctate.

Capartogramma is monotypic in North America (C. crucicula [Grunow ex Cleve] Ross). This species is found in rivers of varying conductance in the eastern and southern US. It is also common in tropical areas, particularly oceanic islands.