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Diatoms of the United States is now known as Diatoms of North America.
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Kociolek & Stoermer 1987      Category: Asymmetrical biraphid
TYPE SPECIES: Reimeria sinuata Kociolek & Stoermer




Smallest to largest - 3 taxa sorted by maximum length

Image Credit: Marina Potapova

CLASS: Bacillariophyceae
  ORDER: Cymbellales

  1. Ventral margin straight to slightly convex
  2. Ventral margin at central area tumid
  3. Stigma single, positioned dorsally in central area

Valves of Reimeria are symmetrical to the transapical axis and asymmetrical to the apical axis. The dorsal margin is slightly arcuate. The ventral margin is markedly expanded, or tumid, at the central area. Apical porefields are present at both poles on the ventral margin and bisected by the terminal raphe ends. The axial area is narrow. A single stigma is positioned on the dorsal side of the central area. Distal raphe ends are deflected toward the ventral margin.

Reimeria contains a few species, two of which are broadly distributed across North America in benthic habitats. Older literature contains this group within the Cymbella sinuata complex.

Cite This Page:
Spaulding, S., and Edlund, M. (2008). Reimeria. In Diatoms of the United States. Retrieved May 22, 2018, from

Contributor: Sarah Spaulding | Mark Edlund - December 2008
Reviewer: Sam Rushforth - June 2010