Planktothrix K.Anagnostidis & J.Komárek, 1988
Holotype species: Planktothrix agardhii (Gomont) Anagnostidis & Komárek
Original publication and holotype designation: Anagnostidis, K. & Komárek, J. (1988). Modern approach to the classification system of cyanophytes. 3. Oscillatoriales. Archiv für Hydrobiologie, Supplement 80: 327-472, 35 figs, 13 tables.
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Komárek, J., Kaštovský, J., Mares, J. & Johansen, J.R. (2014). Taxonomic classification of cyanoprokaryotes (cyanobacterial genera) 2014, using a polyphasic approach. Preslia 86: 295-335.
Description: Filaments solitary, rarely in small irregular and easy disintegrating fascicles (groups) (in the mass developments), more or less straight or slightly waved, isopolar, free living; usually growing without sheath. Sheaths occur facultatively in several species, in typical planktonic species only under unfavorable conditions; they are fine, thin, colorless, joined to the trichome, opened at the apex. Trichomes with cylindrical cells, slightly constricted at the crosswalls, sometimes slightly tapering to the ends, to 4 mm long, 3.5-10 _m wide; occasionally with slight movement (trembling). Cells slightly shorter than wide to Å isodiametric, rarely slightly longer than wide, with aerotopes through the whole cell volume (but sometimes without gas vesicles in parts of trichomes); end cells (when fully developed) widely rounded or slightly narrowed and with thickened outer cell wall or with calyptra. Without chromatic adaptation, with Å constant phycobilin ratios. Presence of carotenoids myxoxanthophyll and oxillaxanthin. False branching, heterocytes and akinetes absent. Cell division crosswise, the cells grow to the original size before the next division. Meristematic zones irregular (?). Reproduction by trichome disintegration into hormogonia, by help of necridic cells. Almost all species are planktonic, few of them causing the water blooms, mainly in mesotrophic to eutrophic reservoirs (usually lakes). One species (P. cryptovaginata) grows in metaphyton of unpolluted pools and ponds among submersed aquatic plants. Two species have cosmopolitan distribution, other ones are geographically limited, mainly occurring under special ecological situations; two species are known from tropics only. Emended by Suda et al. (2002: 1592). Emended by Wang & Li (liu et al. 2013: 330).
Information contributed by: J. Komárek. The most recent alteration to this page was made on 6 May 2015 by Salvador Valenzuela Miranda.
Numbers of names and species: There are 21 species names in the database at present, as well as 1 infraspecific names. Of the species names, 16 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.
Suda, S., Watanabe, M., Otsuka, S., Mahakahant, A., Yongmanitchai, W., Nopartnaraporn, N., Liu, Y. & Day, J.G. (2002). Taxonomic revision of water-bloom-forming species of oscillatorioid cyanobacteria. International Journal of Systematic and Evolutionary Microbiology 52: 1577-1595.
Thomazeau, S., Houdan-Fourmont, A., Couté, A., Duval, C., Couloux, A., Rousseau, F. & Bernard, C. (2010). The contribution of sub-Saharan African strains to the phylogeny of cyanobacteria: focusing on the Nostacaceae (Nostocales, Cyanobacteria). Journal of Phycology 46(3): 564-579.
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: 06 May 2015 by Salvador Valenzuela Miranda
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43608
Please cite this record as:
Salvador Valenzuela Miranda in Guiry, M.D. & Guiry, G.M. 2021. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 28 July 2021.