Symbiodinium Freudenthal, 1962: 52
Classification:
Empire Eukaryota
Kingdom Protozoa
Subkingdom Biciliata
Infrakingdom Alveolata
Phylum Myzozoa
Class Dinophyceae
Order Suessiales
Family Symbiodiniaceae
Holotype species: Symbiodinium microadriaticum Freudenthal
Original publication and holotype designation: Freudenthal, H.D. (1962). Symbiodinium gen. nov. and Symbiodinium microadriaticum sp. nov., a Zooxanthella: taxonomy, life cycles and morphology. Journal of Protozoology 9: 45-52.
Taxonomic status: currently recognized as a distinct genus.
Taxonomic notes
Order: Gymnodiniales; Family: Gymnodiniaceae (Trench & Blank 1987: 478). - (18 Dec 2009) - Wendy Guiry
Description: Unicellular, marine, phototrophic dinophytes known as intracellular symbionts of invertebrates; intercellular symbionts of some marine invertebrates have been reported, but the generic affinity of these symbionts must be confirmed. In their hosts, they occur predominantly as coccoid cells of roughly spherical shape, and under karyokinesis and cytokinesis only in the coccoid state. In their host, reproduction is by binary fission; in culture outside their host, 4 daughter cells also may be produced. Coccoid cells have a continuous cell wall, underlain by a series of membranes. One to several chloroplasts with thylakoids stacked in groups of 3, pyrenoid single without invasive chloroplast thylakoids, enclosed by a triple-layered chloroplast envelope. Nucleus of typical dinokaryon structure with about 70-100 chromosomes. Motile cells of typical gymnodinoid morphology are produced with a characteristic daily rhythm in culture. Hypocone somewhat smaller than epicone, with characteristic thecal plates in vesicles and with associated microtubules, a longitudinal flagellum without flagellar hairs and a ribbon-like transverse flagellum.
Comments: Widely distributed mainly in tropical and subtropical regions. The "zooxanthellae" of invertebrates are contributing a large amount to the carbon fixation and to the nutrition of corals. Up to 6 mg fixed C per m2 per day have been reported. Emended by Trench & Blank (1987: 478). Dodge (1982: 132) notes that this genus is a synonym of Zooxanthella Brandt
NCBI Nucleotide Sequences
Numbers of names and species: There are 15 species (and infraspecific) names in the database at present, of which 11 have been flagged as currently accepted taxonomically.
Names: ('C' indicates a name that is currently 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):
Symbiodinium bermudense R.K.Trench C
Symbiodinium californium C
Symbiodinium cariborum R.K.Trench C
Symbiodinium corculorum R.K.Trench C
Symbiodinium goreaui Trench & Blank C
Symbiodinium goreauii R.K.Trench & R.J.Blank S
Symbiodinium kawagutii R.K.Trench & R.J.Blank S
Symbiodinium kawagutii Trench & Blank C
Symbiodinium meandrinae R.K.Trench C
Symbiodinium microadriaticum subsp. condylactis Blank & Huss C
Symbiodinium microadriaticum Freudenthal C - type
Symbiodinium natans Gert Hansen & Daugbjerg C
Symbiodinium pilosum R.K.Trench & R.J.Blank S
Symbiodinium pilosum Trench & Blank C
Symbiodinium pulchrorum R.K.Trench C
References
Dodge, J.D. (1982). Marine dinoflagellates of the British Isles. pp. 1-303. London: Her Majesty's Stationery Office.
Trench, R.K. & Blank, R.J. (1987). Symbiodinium microadriaticum Freudenthal, S. goreauii sp. nov., S. kawagutii sp. nov. and S. pilosum sp. nov.: gymnodinioid dinoflagellate symbionts of marine invertebrates. Journal of Phycology 23: 469-481.
Information contributed by: M. Elbrächter. The most recent alteration to this page was made on 6 Feb 2010 by M.D. Guiry.
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.
