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Diatoms of the United States is now known as Diatoms of North America.
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Krammer and Lange-Bertalot in Krammer 2000      Category: Symmetrical biraphid
TYPE SPECIES: Hygropetra balfouriana (Grunow ex Cleve) Krammer and Lange-Bertalot in Krammer




Image Credit: Loren Bahls, Pat Kociolek

CLASS: Bacillariophyceae
  ORDER: Naviculales

  1. Striae broad
  2. Striae alveolate
  3. Robust transapical costae

The species in Hygropetra are small in size, with broad, V-shaped striae. The striae are alveolate, or composed of very small pores, in rows of 3-4. A small septum is present. Internally, robust transapical costae are positioned between the striae. The raphe is filiform, with a relatively large gap between proximal raphe ends.

Hygropetra is a genus of small taxa previously considered within Pinnularia. The group is typical of low nutrient, northern temperate and arctic lakes and mosses.

Cite This Page:
Spaulding, S., and Edlund, M. (2008). Hygropetra. In Diatoms of the United States. Retrieved May 23, 2018, from

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