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Diatoms of the United States is now known as Diatoms of North America.
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(Frenguelli) Frenguelli 1945      Category: Symmetrical biraphid
TYPE SPECIES: Muelleria linearis (O. Muller) Frenguelli




Image Credit: Sarah Spaulding

CLASS: Bacillariophyceae
  ORDER: Naviculales

  1. External proximal raphe ends deflected to one side
  2. Longitudial canals two, one on each side of the raphe

The outline of valves of Muelleria is linear, linear-elliptical or panduriform. The external proximal raphe ends are distinctive for their unilateral deflection. Distal raphe ends are branched. A longitudinal canal is present on each side of the raphe. Areolae are loculate. Living cells contain four plastids.

Muelleria gibbula and M. terrestris appear to be widespread in aerophilic habitats, in association with soils, mosses, and ephemeral pools of the mid-western and western United States. Several species within the genus are geographically restricted to the Arctic, Antarctic or South America.

Cite This Page:
Spaulding, S., and Edlund, M. (2008). Muelleria. In Diatoms of the United States. Retrieved May 24, 2018, from

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