160,972 species and infraspecific names are in the database, 22,718 images, 62,582 bibliographic items, 473,221 distributional records.

Pyrophacus F.Stein, 1883

Empire Eukaryota
Kingdom Chromista
Subkingdom Harosa (supergroup SAR)
Infrakingdom Halvaria
Phylum Miozoa
Subphylum Myzozoa
Infraphylum Dinozoa
Superclass Dinoflagellata
Class Dinophyceae
Order Gonyaulacales
Family Pyrocystaceae
Subfamily Pyrophacoideae

Holotype species: Pyrophacus horologium F.Stein

Original publication and holotype designation: Stein, F. (1883). Die naturgeschichte der arthrodelen Flagellaten. In: Der Organismus der Infusionstiere. III. Pt. 2. ( Eds), pp. 1-30. Leipzig:

Taxonomic status: currently recognized as a distinct genus.

Gender: This genus name is currently treated as masculine.

Most recent taxonomic treatment adopted: Tillmann, U., Bantle, A., Krock, B., Elbrächter, M & Gottschling, M. (2021). Recommendations for epitypification of dinophytes exemplified by Lingulodinium polyedra and molecular phylogenetics of the Gonyaulacales based on curated rRNA sequence data. Harmful Algae 103: [1-16], 8 figs, 3 tables.

Description: Unicellular phototrophic, biflagellate heterodynamic cells of various size (30-1190 µm) with cell walls of cellulosic plates. Plate number of episome and hyposome is highly variable, often with broad intercalary bands. Plate formula : Po, 5-8', 9-12", 9-14c, 8s, 9-14"', 1-11p, 3"". The pore plate has a characteristic fishhook-shaped pore. Cells are lenticular in shape, strongly compressed anterio-posteriorly, with equal or subequal altitude of episome and hyposome. In apical and antapical view cells are round with a characteristic concavity at the ventral area. Cingulum is equatorial, deeply impressed, without displacement. Sulcus restricted to the hyposoma, sulcal lists present. Chloroplasts golden-brown, numerous. Vegetative reproduction by binary fission inside the mother cell, daughter cells hatch from the mother cell wall and form a new theca; some authors reported the formation of four daughter cells. Sexual reproduction is anisogamous and heterothallic. Male gametes are smaller and rounder than vegetative cells whereas female gametes cannot be distinguished from vegetative cells. Eight or 16 male gametes are released by one cell. Fusion of the anisogamets occurs during the dark period, the resulting planozygote swims for two to three days before becoming non-motile. The hypnozygote produces the typical dumbbell-shaped cysts in about one week. The cysts have been described as separate cyst genus : Tuberculodinium Wall. These cysts have been found as fossils back to the Pleistocene. Habitat: Marine plankton from tropical to cold-temperate waters in all oceans. Tolerates brackish waters, e.g, in the Baltic Sea.

Information contributed by: M. Elbrächter. The most recent alteration to this page was made on 5 Mar 2021 by M.D. Guiry.

Numbers of names and species: There are 3 species names in the database at present, as well as 2 infraspecific names. Of the species names, 2 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.

Bérard-Therriault, L., Poulin, M. & Bossé, L. (1999). Guide d'identification du phytoplancton marin de l'estuaire et du Golfe du Saint-Laurent incluant également certains protozoaires. Publication Spéciale Canadienne des Sciences Halieutiques et Aquatiques 128: 1-387.

Dodge, J.D. (1982). Marine dinoflagellates of the British Isles. pp. 1-303, 35 figs, pls I-VIII. London: Her Majesty's Stationery Office.

Steidinger, K.A. & Tangen, K. (1996). Dinoflagellates. In: Identifying Marine Phytoplankton. (Tomas, C.R. Eds), pp. 387-584. San Diego: Academic Press.

Li, Z. & Shin, HH. (2019). Morphology, phylogeny and life cycle of Fragilidium mexicanum Balech (Gonyaulacales, Dinophyceae) . Phycologia 58(4): 419-432.

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: 07 May 2002 by M.D. Guiry

Verified by: 05 March 2021 by M.D. Guiry

Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=44688

Citing AlgaeBase
Please cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2021. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 11 April 2021.

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