Visit us at

Diatoms of the United States is now known as Diatoms of North America.
This site has been redesigned and updated, and will be closing soon.


Ehrenberg 1842      Category: Araphid
TYPE SPECIES: Staurosira construens Ehrenberg




Image Credit: Eduardo Morales

CLASS: Fragilariophyceae
  ORDER: Fragilariales
    FAMILY: Fragilariaceae

  1. Striae narrow, composed of small, round or somewhat elongated areolae
  2. Striae do not meet in central sternum

Staurosira valves are elliptical or cruciform in outline. In girdle view, the frustules are rectangular in shape. Cells often form colonies, joined by interlinking spines. The striae are narrow and composed of small, round areolae. Striae do not meet one another in the central sternum. Valves lack rimoportulae.

Staurosira includes the former Fragilaria construens and its relatives. In the light microscope it can be distinguished from Staurosirella based on the structure of the striae. The striae of Staurosira are composed of round areolae, while the striae of Staurosirella are lineolate.

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

Contributor: Sarah Spaulding | Mark Edlund - December 2008