Home / Charophyceae / Desmids / Unicells/ Placoderm / Docidium
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Name derivation:
Classification:
Docidium Brébisson ex Ralfs 1848; 17 of 97 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Desmidiales; Family Desmidiaceae
Morphology:
Green unicells, cylindrical. Lateral walls are usually undulate, occasionally smooth with truncate end walls. Isthmus is nearly as wide as the cell (slightly constricted).
Similar genera:
Several genera of cylindrical placoderm desmids can be confusing until somewhat minor variations in wall shapes and decor are scrutinized. The most common include Docidium, Gonatozygon, Penium, Pleurotaenium, Roya and Triploceras.
Habitat:
Freshwater somewhat acidic oligotrophic lakes.Widespread but sparse. Often found in Sphagnum ‘squeezings’ (Brook and Johnson 2011).
References:
Brook, A.J., and L.R. Johnson 2011. Order Zygnematales. In: John, D.M., B.A. Whitton and A.J. Brook (Eds.) The freshwater algal flora of the British Isles. Cambridge University Press. (878 pp.). Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 28 July 2013. Ralfs, J. 1848. The British Desmidieae. pp. [i]-xxii, [i], [1]-226, pls I-XXXV. London: Reeve, Benham and Reeve.