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Diatoms of the United States is now known as Diatoms of North America.
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Kützing 1844      Category: Nitzschioid
TYPE SPECIES: Denticula tenuis Kützing




Smallest to largest - 3 taxa sorted by maximum length

Image Credit: Pat Kociolek, Nina Desianti, Ian Bishop

CLASS: Bacillariophyceae
  ORDER: Bacillariales
    FAMILY: Bacillariaceae

  1. Raphe eccentric, on a wide, low marginal keel
  2. Internal fibulae distinct, thickened

The raphe system of each valve is positioned diagonally opposite to one another, demonstrating nitzschiod symmetry. The raphe system is located within a wide, low keel. The raphe may or may not have proximal raphe ends or be continuous across the valve, a feature difficult to see without SEM. Thick internal bars of silica (fibulae) are present and parallel to the striae. The fibulae widen near the valve margins to form a ‘tooth-like’ appearance, hence the genus name Denticula.

Denticula species occur in rather diverse habitats. Some species may be locally abundant in carbonate rich waters of moderate conductivity. The genus also contains species characteristic of large oligotrophic lakes, as well as warm springs.

Cite This Page:
Spaulding, S., and Edlund, M. (2008). Denticula. In Diatoms of the United States. Retrieved May 22, 2018, from

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