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Name derivation:

Greek Baccill (Bacul) meaning a staff ; aria meaning connected.



Bacillaria J.F.Gmelin, 1791;  8 of 65 species descriptions are currently accepted taxonomically (Guiry and Guiry 2014).

Order Bacillariales;  Family Bacillariaceae

May be the first genus of diatoms described.



Individual cells are elongate and have a keeled raphe near the center of each cell. The cells form colonies where cells 'slip and slide' back and forth past each other, nearly losing touch at the end of each passage. The cells are held together by interlocking ridges and grooves that are formed on raphe. The valve face is flat and the cell contains two plastids positioned near the poles.

Similar genera:

Bacillaria is similar to Nitszchia. Both can form the same type of colonies, but Bacillaria is the only diatom that exhibits this type of motility.


Bacillaria is found in brackish water and occasionally high conductivity fresh water. Colonies are normally epipelic but can be found in shallow waters.



Guiry, M.D. and G.M. Guiry  2013.  AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 30 May  2014.

Round, F. E., Crawford, R. M., Mann, D. G. 1990. The Diatoms. Cambridge University Press. New York, NY.

Wehr, J., Sheath, R. 2003. Freshwater Algae of North America Ecology and Classification. Academis Press. San Diego, CA.