(Patrick) Lange-Bertalot 2000      Category: Symmetrical biraphid
TYPE SPECIES: Decussata placenta (Patrick) Lange-Bertalot and Metzeltin in Lange-Bertalot




Image Credit: Pat Kociolek

CLASS: Bacillariophyceae
  ORDER: Naviculales

  1. Valves linear to linear-lanceolate
  2. Striae punctate
  3. Striae decussate

Decussata valves are linear to linear-lanceolate, with slightly rostrate ends. The striae are punctate, comprised of distinct, round areolae. The striae are decussate, meaning they appear to be organized into rows - a transapical row and two oblique rows.

Decussata includes two species, including the former Navicula placenta. Decussata placenta grows in low nutrient, slightly acidic seeps in Iowa. It is also known from moss and aerophilic habitats.

Cite This Page:
Spaulding, S., and Edlund, M. (2008). Decussata. In Diatoms of the United States. Retrieved April 26, 2018, from

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


April 17th, 2012 - Correction of authorship

The authorship of the genus Decussata was previously given as (Patrick) Lange-Bertalot. It was corrected to (Patrick) Lange-Bertalot and Metzeltin in Lange-Bertalot. - S. Spaulding