Xanthidium Ehrenberg ex Ralfs, 1848
Lectotype species: Xanthidium aculeatum Ehrenberg ex Ralfs
Original publication: Ralfs, J. (1848). The British Desmidieae The drawings by Edward Jenner, A.L.S. pp. [i]-xxii, [i], [1]-226, 35 pls. London: Reeve, Benham & Reeve, King William Street, Strand.
Request PDFType designated in: Guiry, M.D. (2013). Taxonomy and nomenclature of the Conjugatophyceae (=Zygnematophyceae). Algae. An International Journal of Algal Research 28: 1-29.
Description: Cells solitary, slightly compressed (biradiate) with deep median constriction (isthmus) where semicell walls overlap. Each semicell usually with four or more, simple or furcate, 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, a central incrassate area, a line of small verrucae, or a protuberance bearing short or long spines. Cell wall with scattered cylindrical pores through which a narrow or broad gelatinous sheath secreted. Chloroplasts two to many, each with one or more pyrenoids. Nucleus in isthmus. Asexualreproduction by cell division and formation of new semicells typical of Cosmarium-type desmids (see Cosmarium). Sexual reproduction by conjugation. Gametes fuse between gametangia; zygospores spherical with simple or furcate, short or long spines. Several species of Xanthidium common and cosmopolitan; usually in acidic, oligotrophic ponds and lakes.
Information contributed by: J.F. Gerrath. The most recent alteration to this page was made on 2013-09-12 by M.D. Guiry.
Taxonomic status: This name is of an entity that is currently accepted taxonomically.
Most recent taxonomic treatment adopted: Guiry, M.D. (2013). Taxonomy and nomenclature of the Conjugatophyceae (=Zygnematophyceae). Algae. An International Journal of Algal Research 28: 1-29.
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Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera,
organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA)
and intended to be published in CD format.
These AlgaeBase descriptions are now being continually updated, and each current contributor is identified above.
The PSA and AlgaeBase warmly acknowledge the generosity of all past and present contributors and particularly the work of Dr Parker.
Descriptions of chrysophyte genera were subsequently published in J. Kristiansen & H.R. Preisig (eds.). 2001. Encyclopedia of Chrysophyte Genera. Bibliotheca Phycologica 110: 1-260.
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Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 12 September 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 25 November 2024
