Ophiocytium Nägeli, 1849, nom. cons.
Holotype species: Ophiocytium apiculatum Nägeli
Original publication and holotype designation: Nägeli, C. (1849). Gattungen einzelliger Algen, physiologisch und systematisch bearbeitet. Neue Denkschriften der Allg. Schweizerischen Gesellschaft für die Gesammten Naturwissenschaften 10(7): i-viii, 1-139, pls I-VIII.
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Ott, D.W. & Oldham-Ott, C.K. (2003). Eustigmatophyte, Raphidophyte, And Tribophyte. In: Freshwater Algae of North America, Ecology and Classification. (Wehr, J.D. & Sheath, R.G. Eds), pp. 423-470. San Diego: Academic Press.
Description: Unicellular or colonial, free-living or attached organisms 9-2500 µm long and 2-27 µm wide. Colonies dendroid. Cells cylindrical, elongated, straight, spiralled, sigmoid or semi-circular, sometimes swollen and with rounded extremities, with or without spine (3-15 µm long) or pedicel (3-35 µm long). When present, pedicel frequently terminated by a brownish disk which attaches organism to substratum. Cell wall thin or thick, strong and sometimes brown, formed in two unequal portions. The basal portion is tubular and elongates along with the cell; the second portion at the free apex of the cell has a constant size. Young cells always uninucleate, becoming multinucleate with age. Chloroplasts (single to numerous) discoid, stellate, ribbon-shaped or H-shaped in optical section, parietal and green, yellow green or blue green. Pyrenoids absent. Cytoplasm with numerous oil or dark red lipid globules. Asexual reproduction by zoosporulation or autosporulation. Zoospores with two unequal flagella, two chloroplasts and, without doubt, no stigma, formed in twos or fours in each mother cell. Zoospores released by a raising of the apcial cell wall piece. After a short swimming period , they attach to the edge of the basal cell wall portion and develop into new vegetative cells, thus forming a dendroid colony. Autospores liberated similar to zoospores. Thick-walled cysts also produced.
Information contributed by: H.R. Preisig & I.M. Franceschini. The most recent alteration to this page was made on 20 Oct 2015 by M.D. Guiry.
Comments: Ophiocytium species are planktonic, tychoplanktonic or epiphytic on filamentous algae in freshwater; cosmopolitan. Species are distinguished based on the free-living or attached nature of the organism, whether it is free-living or attached. Colony morphology, cell diameter, presence or absence and length and morphology of apical spines and pedicel and symmetry (or lack of) of the poles are also important specific characters.
Numbers of names and species: There are 29 species names in the database at present, as well as 15 infraspecific names. Of the species names, 18 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: 20 October 2015 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43831
Please cite this record as:
M.D. 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 23 January 2019.