Trichodesmiumex Gomont, 1892, nom. cons.
Lectotype species: Trichodesmium erythraeum Ehrenberg ex Gomont
Original publication:Gomont, M. (1892 '1893'). Monographie des Oscillariées (Nostocacées Homocystées). Deuxième partie. - Lyngbyées. Annales des Sciences Naturelles, Botanique, Série 7 16: 91-264, pls 1-7.
Type designated in Geitler, L. (1942). Schizophyta: Klasse Schizophyceae. In: Die natürlichen Pflanzenfamilien, Sweite Auflage. (Engler, A. & Prantl, K. Eds) Vol.1b, pp. 1-232. Leipzig: Wilhelm Engelmann.
Taxonomic status: currently recognized as a distinct genus.
Gender: This genus name is currently treated as neuter.
Most recent taxonomic treatment adopted: Komárek, J., Kastovsky, J., Mares, J. & Johansen, J.R. (2014). Taxonomic classification of cyanoprokaryotes (cyanobacterial genera) 2014, using a polyphasic approach. Preslia 86: 295-335.
Description: Filamentous-colonial; trichomes straight or curved, free-floating, unified parallel into fascicles or radially into elongated or spherical, small colonies by the help of fine, unstructured, diffluent, colorless, homogeneous mucilage. Trichomes slightly motile, 6-22 _m wide, at the ends sometimes attenuated to conspicuously attenuated with elongated and hyaline terminal cells, or not attenuated, only with a rounded or narrowed terminal cell, sometimes with a calyptra, constricted or unconstricted at the crosswalls, multicelled, simple, uniseriate, unbranched, without firm sheaths. Cells more or less isodiametric or slightly shorter or longer than wide, cylindrical or barrel-shaped, to the ends sometimes elongated, with plenty of aerotopes; thylakoids are irregularly coiled near the cell walls to through the whole cell content. In Trichodesmium species were found special ecophysiological properties (valid only for marine species ?), e.g., the special type of "strong" gas vesicles, capacity for nitrogen fixation, low molecular weight of fatty acid composition. Heterocytes and akinetes absent. Cell division by the crosswise fission of all cells, with exception of apical ones. The cells grow into original size before the next division. Reproduction by fragmentation of trichomes into motile hormogonia by help of necridic cells and by dissociation of colonies. Hormogonia germinate at both ends (isopolar). Strictly planktonic species, from which three are freshwater (rarely occurring in large reservoirs), the other are marine. They cause sometimes reddish water blooms in tropical seas and oceans, sometimes in lower layers (several meters under the water level).
Information contributed by: J. Komárek. The most recent alteration to this page was made on 19 Oct 2015 by M.D. Guiry.
Numbers of names and species: There are 16 species names in the database at present, as well as 5 infraspecific names. Of the species names, 10 have been flagged as accepted taxonomically on the basis of the listed literature under the species name. In some instances, opinions on taxonomic validity differ from author to author and users are encouraged to form their own opinion. AlgaeBase is a work in progress and should not be regarded as a definitive source only as a guide to the literature..
Names: ('C' indicates a name that is accepted taxonomically; 'S' a homotypic or heterotypic synonym; 'U' indicates a name of uncertain taxonomic status, but which has been subjected to some verification nomenclaturally; 'P' indicates a preliminary AlgaeBase entry that has not been subjected to any kind of verification. For more information on a species click on it to activate a link to the Species database):
Click here to also show infraspecific names in the list below.
Verification of data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.
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.
Created: 05 March 2001 by Wendy Guiry
Verified by: 19 October 2015 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43303
Please cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2019. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 21 March 2019.