Home / Diatoms / Pennate / Unicells / Biraphes / Asymmetric / Epithemia

 

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Name derivation:

Classification:

Epithemia  Kützing  1844;  26 of 264 species descriptions are currently accepted taxonomically (Guiry and Guiry 2014).

Order Rhopalodiales;  Family Rhopalodiaceae

Morphology:

Solitary cells that can be motile and almost always occur in girdle view. The cells appear elliptical with flat truncate ends. The cell appears as a large slice of orange. The valves are asymmetrical and are sometimes smaller or constricted at each end of the cell. Both raphes lie on the same side of the valve. There are generally two or more plastids that occur in different positions throughout the cell.

Similar genera:

 

 

Habitat:

Epiphytic on plants, stones and mud. A large mainly marine genus with relatively few species in freshwater.

 

References:

Guiry, M.D. and G.M. Guiry  2014.  AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 08 May 2014.

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