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Diatoms of the United States is now known as Diatoms of North America.
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Krammer 2003      Category: Asymmetrical biraphid
TYPE SPECIES: Cymbella delicatula Krammer




Image Credit: Ian Bishop, Loren Bahls

CLASS: Bacillariophyceae
  ORDER: Cymbellales
    FAMILY: Cymbellaceae

  1. Valves narrow, slightly asymmetric to apical axis
  2. Terminal raphe fissures deflected dorsally

Valves are slightly asymmetric to the apical axis and symmetric to the transpical axis. The valve shape is narrow and lanceolate. The raphe is distinctly lateral and becomes reverse-lateral at the proximal ends. The terminus of the raphe is thin, comma shaped, and terminal raphe fissures are deflected toward the dorsal side. Valves lack a distinct central area. Stigmata are absent. The striae are fine and usually number more than 18 in 10 ┬Ám.

Delicata was recently segregated from Cymbella sensu lato.

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

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