Tetrasporaex Desvaux, 1818
Lectotype species: Tetraspora gelatinosa (Vaucher) Desvaux
Original publication:Desvaux, N.A. (1818). Observations sur les plantes des environs d'Angers, pour servir de supplément a la flore Maine et Loire, et de suite à l'histoire naturelle et critique des plantes de France. pp. -188. Angers & Paris: Chez Fourier-Mame, Libraire, rue Saint-Laud; Dondey-Dipré, Libraire, no. 46, au Marais.
Type designated in Agardh, C.A. (1824). Systema algarum. pp. [i]-xxxvii, -312. Lundae [Lund]: Literis Berlingianis [Berling].
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Tsarenko, P.M. (2011). Tetrasporales. In: Algae of Ukraine: diversity, nomenclature, taxonomy, ecology and geography. Volume 3: Chlorophyta. (Tsarenko, P.M., Wasser, S.P. & Nevo, E. Eds), pp. 225-232. Ruggell: A.R.A. Gantner Verlag K.-G..
Description: Spherical to amorphous or highly elongate cylindrical to irregular colonies with tens to thousands of cells embedded in mucilaginous matrix 10-40 &m thick. Some species saccate or perforate when mature. Cells scattered or arranged in groups of 2 or 4 often with sheath boundaries remaining distinct within wall matrix, although becoming more confluent as each cell generation produces more mucilage. Cells spherical to oval 6-12 &m diameter with pair of anterior pseudoflagella at least several times cell length, projecting towards exterior of colony; in some species pseudoflagella project beyond colony envelope. Cells uninucleate with two anterior contractile vacuoles (not apparent in T. hexanematoidea); single chloroplast parietal and cup shaped; pyrenoid basal with conspicuous starch sheath; stigma absent. Colony growth by mitotic division of cells. Asexual reproduction by zoospores, akinetes and colony fragmentation. Zoospores 6-12 x 4-7 &m, with production in T. gelatinosa controlled by temperature with inhibition at 3 C and extensive release at 1 and 23 C. Thick walled akinetes described for some species (e.g., T. lemmermannii, T. gelatinosa). Isogamous sexual reproduction described for two species. Gametes biflagellate and differentiated into plus and minus strains that respond to sex attractants produced by opposing strain. Site of meiosis unknown but presumed to be on germination of the zygote. Tetraspora benthic (attached or unattached) or planktonic, mostly in freshwater lakes and ponds; genus cosmopolitan although some species apparently with restricted distributions. Pseudoflagella without central pair of microtubules in axoneme with outer pairs of microtubules disorganized and occasionally single. Mitosis similar to Chlamydomonas with cytokineses via typical phycoplast. Species distinguished based on colony morphology, structure of mucilaginous matrix and form of starch sheath around pyrenoids. Over a dozen additional taxa have been described in Tetraspora; for the most part these have been synonymized with other species or referred to Paulschulzia.
Information contributed by: D. Garbary & P. Kugrens. The most recent alteration to this page was made on 29 Jun 2012 by Michael Guiry.
Numbers of names and species: There are 33 species names in the database at present, as well as 6 infraspecific names. Of the species names, 19 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: 11 April 2002 by M.D. Guiry
Verified by: 29 June 2012 by Michael Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43486
Please cite this record as:
Michael 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 October 2019.