Raphidonema Lagerheim, 1892

Holotype species: Raphidonema nivale Lagerheim

Original publication and holotype designation: Lagerheim, G. (1892). Die Schnee Flora des Pinchincha. Ein Beitrag zur Kenntnis der Nivalen Algen und Pilzen. Bericht der Deutschen Botanischen Gessellschaft 10: 517-534, pl. XXVIII.

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Description: Filaments relatively short, unbranched and uniseriate, (2-) 4-16 (-32) celled, straight or slightly bent, not specifically attached. Interjacent central cells cylindrical, polar cells acuminate or gradually tapering into bristle-like point. Cell membrane tiny, thin, hyaline without mucilaginous sheath. Chloroplast single, parietal, laminate or girdle-shaped, without pyrenoids. Asexual reproduction only by vegetative propagation of filaments. Cell multiplication by vegetative cell division. Method of sexual reproduction unknown. Raphidonema widely distributed and cryobiontic; in large quantities producing distinct green snow, up to several cm deep. Because of its filamentous growth habit, Raphidonema closely resembles the typically ulotrichalean Gleotila Kützing, differing by presence of pointed polar cells. Raphidonema may have evolved from Koliella by delayed separation of cells following cell division. Ultrastructure of cell division supports placement in charophycean line. Critical features include presence of persistent telophase spindles that widely separate daughter nuclei, and centripetal ingrowth of septum that not associated with phycoplast.

Information contributed by: G.M. Lokhorst. The most recent alteration to this page was made on 2016-02-27 by M.D. Guiry.

Taxonomic status: This name is of an entity that is currently accepted taxonomically.

Most recent taxonomic treatment adopted: John, D.M. (2002). Orders Chaetophorales, Klebshormidiales, Microsporales, Ulotrichales. In: The Freshwater Algal Flora of the British Isles. An identification guide to freshwater and terrestrial algae. (John, D.M., Whitton, B.A. & Brook, A.J. Eds), pp. 433-468. Cambridge: Cambridge University Press.

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Contributors
Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera, organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA) and intended to be published in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.

Linking to this page: https://www.algaebase.org/search/genus/detail/?genus_id=43513

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 27 February 2016. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 22 November 2024