Chlorophysema Pascher, 1927

Lectotype species: Chlorophysema apiocystiforme (A.P.Artari) Pascher

Original publication: Pascher, A. (1927). Die Süsswasser-Flora Deutschlands, Österreichs und der Schweiz. Volvocales = Phytomonadinae. Vol. 4 pp. 505. Jena: Fischer.

Type designated in: Fott, B. (1972). Chlorophyceae (Grünalgen). Ordnung: Tetrasporales. In: Das Phytoplankton des Süsswassers...6. Teil. (Huber-Pestalozzi, G. Eds), pp. i-x, 1-116. Stuttgart: Schweizerbart.

Description: Thalli initially unicellular but becoming colonial with colonies 17-90 µm in maximum dimension during zoospore formation with up to eight flagellated or non-flagellated cells contained within common wall. Colony wall usually thin and smooth but much thicker and with irregular roughening in C. contractum and C. ampliatum. Cells 6-30 µm, spherical to elliptic with smooth cell walls. Cells with two apical contractile vacuoles and nonpersistent stigma. Cells uninucleate; single chloroplast parietal and cup-shaped with single basal or lateral pyrenoid. C. chlorastra with stellate chloroplast. Asexual reproduction by biflagellate zoospores; 2, 4, or 8 per sporangium. Zoospores, 7-20 x 3-5 µm, ovate to spherical, released by tear in top of sporangial wall. After short swimming period zoospores attach by apical end, loose flagellae and secrete basal bad and/or short stipe. After considerable expansion of outer wall flagellated or non-flagellated cell becomes free within envelope. Sexual reproduction unknown. Chlorophysema mostly epiphytic on plankton or benthic substrata in freshwater; reported only from Europe. Species distinguished based on differences in cell size and shape Thalli initially unicellular but becoming colonial with colonies 17-90 µm in maximum dimension during zoospore formation with up to eight flagellated or non-flagellated cells contained within common wall. Colony wall usually thin and smooth but much thicker and with irregular roughening in C. contractum and C. ampliatum. Cells 6-30 µm, spherical to elliptic with smooth cell walls. Cells with two apical contractile vacuoles and nonpersistent stigma. Cells uninucleate; single chloroplast parietal and cup-shaped with single basal or lateral pyrenoid. C. chlorastra with stellate chloroplast. Asexual reproduction by biflagellate zoospores; 2, 4, or 8 per sporangium. Zoospores, 7-20 x 3-5 µm, ovate to spherical, released by tear in top of sporangial wall. After short swimming period zoospores attach by apical end, loose flagellae and secrete basal bad and/or short stipe. After considerable expansion of outer wall flagellated or non-flagellated cell becomes free within envelope. Sexual reproduction unknown. Chlorophysema mostly epiphytic on plankton or benthic substrata in freshwater; reported only from Europe. Species distinguished based on differences in cell size and shape.

Information contributed by: M.D.Guiry. The most recent alteration to this page was made on 2012-01-25 by M.D. Guiry.

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

Most recent taxonomic treatment adopted: Masjuk, N.P. & Lilitska, G.G. (2011). Volvocales. In: Algae of Ukraine: diversity, nomenclature, taxonomy, ecology and geography. Volume 3: Chlorophyta. (Tsarenko, P.M., Wasser, S.P. & Nevo, E. Eds), pp. 218-225. Ruggell: A.R.A. Gantner Verlag K.-G..

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=44760

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 25 January 2012. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 22 November 2024