Isocystis A.Borzì ex É.Bornet & C.Flahault, 1886

Lectotype species: Isocystis messanensis Borzì ex Bornet & Flahault

Original publication and holotype designation: Bornet, É. & Flahault, C. (1886 '1888'). Revision des Nostocacées hétérocystées contenues dans les principaux herbiers de France (quatrième et dernier fragment). Annales des Sciences Naturelles, Botanique, Septième Série 7: 177-262.

Request PDF

Description: Filamentous; filaments solitary, in small, microscopic fascicles or in formless, microscopic, gelatinous colonies, attached to the substrate, in metaphyton or free floating, with fine, diffluent, structureless, colorless, sometimes hardly visible gelatinous envelopes. Trichomes uniseriate, simple, curved or coiled, isopolar, usually slightly narrowed to both ends, clearly constricted at crosswalls. Cells barrel-shaped, isodiametrical or longer or shorter than wide, sometimes with solitary granules within cells. Heterocytes missing. Akinetes arise in rows, more or less in the middle of trichomes (apoheterocytic origin), a little larger than vegetative cells, with thick cell walls. All cells capable of division, cell division crosswise, perpendicular to the trichome axis. Reproduction by short hormogonia (sometimes dissociating into solitary cells) and by akinetes. One species grows subaerophytic on wet walls, several are periphytic in different freshwater biotopes (springs, littorals of stagnant water), one species is planktonic, one was described from soil.

Information contributed by: J. Komárek. The most recent alteration to this page was made on 2015-03-04 by M.D. Guiry.

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

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.

Verification of Data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.

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Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera, organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA) and intended to be published in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=45684

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 04 March 2015. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 25 November 2024