Home / Charophyceae / Desmids / Unicells / Placoderm / Xanthidium
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Name derivation:
Classification:
Xanthidium Ehrenberg ex Ralfs 1848; 82 of 521 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013). Order Desmidiales; Family Desmidiaceae
Morphology:
Cells solitary, with deep median where semicell walls overlap. Each semicell usually with four or more, simple. short or long, marginal spines; form and disposition of spines a major morphological feature in species characterization. Middle of each semicell face smooth or with ring or lines of conspicuous pores. Cell wall with scattered cylindrical pores through which a narrow or broad gelatinous sheath secreted. Chloroplasts two to many in number.
Similar genera:
Habitat:
Acid ponds or lakes.
References:
Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 29 January 2013. Ralfs, J. 1848. The British Desmidieae. pp. [i]-xxii, [i], [1]-226, pls I-XXXV. London: Reeve, Benham & Reeve.