Heterocapsa F.Stein, 1883
Holotype species: Heterocapsa triquetra (Ehrenberg) 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.
Most recent taxonomic treatment adopted: Kawai, H. & Nakayama, T. (2015). Introduction (Heterokontobionta p.p.), Cryptophyta, Dinophyta, Haptophyta, Heterokontophyta (except Coscinodiscophyceae, Mediophyceae, Fragilariophyceae, Bacillariophyceae, Phaeophyceae, Eustigmatophyceae), Chlorarachniophyta, Euglenophyta. In: Syllabus of plant families. Adolf Engler's Syllabus der Pflanzenfamilien. Ed. 13. Phototrophic eukaryotic Algae. Glaucocystophyta, Cryptophyta, Dinophyta/Dinozoa, Haptophyta, Heterokontophyta/Ochrophyta, Chlorarachnniophyta/Cercozoa, Chlorophyta, Streptophyta p.p. (Frey, W. Eds), pp. 11-189. Stuttgart: Borntraeger Science Publishers.
Description: Medium-sized (20-40 µm) biflagellated thecate dinoflagellates irregularly spindle-shaped or ovoid with a medium and circular cingulum; sulcus restricted to the hypocone. The plate pattern is difficult to establish and has been disputed. The formula published by Balech (1988a) is: Po, 4, 2a, 7", 6c, 4s, 5'",2"". As in Cachonina, body scales are present in a single layer on the cell surface external to the thecal plates. Numerous chloroplasts and an ovoid nucleus. Cell division takes place in the flagellated stage, with the theca of the mother cell shared by both daughter cells. Sexual reproduction not observed. The lipid fraction contains 24-methylcholesterol, 4,24-dimethylcholestanol, dihydrodinosterol besides cholesterol, the latter present in all dinoflagellates. H. triquetra may form dense blooms with several million cells per liter, causing discoloration in coastal waters. Fish kills related to Heterocapsa blooms apparently are not due to toxicity but rather to oversaturation of the water with oxygen during day time or oxygen deficiency during the decomposition phase. Heterocapsa shows vertical migration over 10 m and more during day-night cycle. Swimming velocity is about 100 _m S-1. Growth rates are up to about 0.7 divisions per day. Marine plankton, worldwide distribution mainly in coastal waters.
Information contributed by: M. Elbrächter. The most recent alteration to this page was made on 23 May 2017 by M.D. Guiry.
Numbers of names and species: There are 22 species names in the database at present, as well as 3 infraspecific names. Of the species names, 19 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.
Sournia, A. (1984). Classification et nomemclature de divers dinoflagellés marins (Dinophyceae). Phycologia 23(3): 345-355.
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: 26 March 2002 by M.D. Guiry
Verified by: 23 May 2017 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43347
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 22 May 2019.