Pseudophormidium (Forti) Anagnostidis & Komárek, 1988

Holotype species: Pseudophormidium phormidioides (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(1-4): 327-472, 35 figs, 13 tables.

Description: Filamentous; filaments solitary, joined into microscopic or macroscopic clusters or mats (strata) covering the substrate, obligatory with firm, irregularly tube-like, colorless sheaths, commonly and intensely irregularly falsely branched, sometimes with 2 parallel trichomes in a sheath. Trichomes often fragmented, cylindrical, isopolar, usually short, irregularly curved and coiled, 1-18 _m wide, uniseriate, composed of barrel-shaped or cylindrical cells, constricted or unconstricted at crosswalls, not attenuated or slightly attenuated to the ends, nonmotile. Cells isodiametrical or slightly longer or shorter than wide, without aerotopes, but usually irregularly granulate or with several prominent granules, blue-green, greyish blue-green or pinkish; end cells rounded or conical-rounded, sometimes with thickened outer cell wall. Heterocytes and akinetes absent. Cell division crosswise, perpendicular to the long axis of a trichome, daughter cells grow Å to the original size before the next division. All cells capable of division, but the indistinct meristematic zones arise. Reproduction by intense and common fragmentation of trichomes into motile hormogonia or nonmotile hormocytes (?), usually by help of necridic cells. Periphytic species, known from soils, different submersed substrates (mainly stones), one species known from streams with rapidly flowing water, another species endogloeic within mucilage of other algae.

Information contributed by: J. Komárek. The most recent alteration to this page was made on 2023-03-03 by M.D. Guiry.

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

Gender: This genus name is currently treated as neuter.

Most recent taxonomic treatment adopted: Strunecký, O., Ivanova, A.P. & Mares, J. (2022 '2023'). An updated classification of cyanobacterial orders and families based on phylogenomic and polyphasic analysis (Review). Journal of Phycology 59(1): 12-51.

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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Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera, organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA) and intended to be published in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=43609

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 03 March 2023. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 23 April 2024