Rabenhorst 1859      Category: Nitzschioid
TYPE SPECIES: Cylindrotheca gerstenbergeri Rabenhorst




CLASS: Bacillariophyceae
  ORDER: Bacillariales
    FAMILY: Bacillariaceae

  1. Frustules very narrow, elongate, with drawn-out ends
  2. Frustules twisted
  3. Frustules very lightly silicified

Cylindrotheca cells are solitary and are characteristically needle-like, thin and elongated in shape. The ends of the cell tend to be drawn out from the center part. The frustules are only lightly silicified. The valves, including the keel and raphe canal, wrap around each other, forming a twisted frustule. As a result of the strong twist of the raphe system, the cells rotate and twirl as they move. The girdle bands are narrow and numerous.

Cylindrotheca is a genus characteristic of high alkalinity habitats. The occurrence of this diatom is often overlooked because the lightly silicified cells are easily broken and destroyed with standard processing techniques. A motto of Dr. Charlie Reimer was “Think like a diatom”, and he preferred to look for Cylindrotheca in the small pools of water that form in cow footprints at Excelsior Fen, Dickinson County, Iowa.

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

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