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) Cleve 1894      Category: Symmetrical biraphid
TYPE SPECIES: Diploneis didyma (Ehrenberg) Cleve




Image Credit: Ditmar Metzeltin

CLASS: Bacillariophyceae
  ORDER: Naviculales

  1. Valves elliptic to panduriform
  2. Longitudinal canals present
  3. Areolae complex

Frustules of Diploneis are typically elliptical to panduriform, with bluntly rounded apices. Each valve possesses two longitudinal canals, one on each side of the raphe. The canals are positioned within the silica cell wall and open to the exterior through pores, but lack openings to the interior of the cell. The function of these canals is uncertain. The frustules are heavily silicified, with complex (loculate) areolae.

The genus Diploneis is large and diverse. Species are primarily from epipelic, marine habitats. There are a few freshwater representatives.

Cite This Page:
Spaulding, S., and Metzeltin, D. (2011). Diploneis. In Diatoms of the United States. Retrieved May 22, 2018, from

Contributor: Sarah Spaulding | Ditmar Metzeltin - February 2011