Diadesmis
Kützing 1844 Category: Symmetrical biraphid
TYPE SPECIES: Diadesmis confervacea Kützing
Image Credit: Marina Potapova, Eugene Stoermer and Sarah Spaulding
CLASS: Bacillariophyceae
ORDER: Naviculales
FAMILY: Diadesmidaceae
- Areolae elongate
- Frustules small, usually less than 20 µm in length
- Cells form band-like colonies
Diadesmis is biraphid, although the raphe often becomes secondarily filled with silica. Frustules of Diadesmis are small, usually less than 30 µm in length. The striae are composed of areolae elongated in the transapical direction, a characteristic that may be difficult to discern in the LM. Frustules form band-like colonies, which may be linked by marginal spines. The raphe systems of many frustules are secondarily filled with silica, and a raphe may not be evident in valve view. In girdle view, however, a central nodule and helictoglossa may be seen - evidence of the presence of a raphe. Living cells contain single, slightly lobed plastid.
Diadesmis is considered an aerophilic taxon. It grows on mosses and on damp rocks, often in low conductivity, slightly acid waters.
Cite This Page:
Spaulding, S., and Edlund, M. (2009). Diadesmis. In Diatoms of the United States. Retrieved May 18, 2013, from http://westerndiatoms.colorado.edu/taxa/genus/Diadesmis
Contributor: Sarah Spaulding | Mark Edlund - January 2009
Reviewer: Sam Rushforth
Citations
Lange-Bertalot, H. and Werum, M. (2001). Diadesmis fukushimae sp. nov. and some other new or rarely observed taxa of the subgenus Paradiadesmis Lange-Bertalot & Le Cohu. Diatom 17: 3-19.
Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.
Van de Vijver, B. Frenot, Y. and Beyens, L. (2002). Freshwater diatoms from Ile de la Possession (Crozet Archipelago, Subantarctica). Bibliotheca Diatomologica 46: 1-412.