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Diatoms of the United States is now known as Diatoms of North America.
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(Ehrenberg) Ralfs in Pritchard 1861      Category: Eunotioid
TYPE SPECIES: Amphicampa alata (Ehrenberg) Ralfs in Pritchard




Image Credit: David Burge

CLASS: Bacillariophyceae
  ORDER: Eunotiales
    FAMILY: Eunotiaceae

  1. Margins distinctly undulate
  2. Raphe short

Amphicampa valves are asymmetric to the apical axis and symmetric to the transapical axis. Both the dorsal and ventral margins of the valves are undulate. The raphe is very short and restricted to the valve ends. The raphe may only be visible through the thickening of the helictoglossa.

A single species, A. eruca Ehrenberg, is found in circumneutral to alkaline waters in the midwest and western United States. This species has also been found in subfossil pothole deposits in Iowa (Julius, unpublished data).

Cite This Page:
Spaulding, S., and Edlund, M. (2009). Amphicampa. In Diatoms of the United States. Retrieved May 24, 2018, from

Contributor: Sarah Spaulding | Mark Edlund - January 2009