Description Cells ovoid, dorsoventrally flattened. Epicone 7–10 μm wide, anteriorly flat, with the right anterior corner ~ 90°, the...
Description Cells ovoid, dorsoventrally flattened. Epicone 7–10 μm wide, anteriorly flat, with the right anterior corner ~ 90°, the left corner extended, approx 30–45°. Cingulum beginning 0.2–0.3 of the cell length from the apex, initially ascending, continuing almost horizontally around the cell; proximal end slightly higher than distal. Hypocone rounded, slightly asymmetrical. Sulcus initially narrow, widening at the posterior end. Apical groove absent. A narrow ventral ridge running between the two points of flagellar insertion. Two pusules present: one obvious, c. 2 μm diam., to the right of the origin of the sulcus; the second less obvious, also c. 2 μm diam., just below and to the left of the proximal end of the cingulum. Nucleus in the posterior part of the hypocone, crescent-shaped or oval, containing very fine chromosomes. One orange-yellow, round, globular inclusion, possibly an eyespot, diameter 6–8 μm. Division by binary fission in the motile cell. [details]
Guiry, M.D. & Guiry, G.M. (2025). AlgaeBase. World-wide electronic publication, National University of Ireland, Galway (taxonomic information republished from AlgaeBase with permission of M.D. Guiry). Amphidinium operculatum Claparède & Lachmann, 1859. Accessed through: Nozères, C., Kennedy, M.K. (Eds.) (2025) Canadian Register of Marine Species at: https://marinespecies.org/carms/aphia.php?p=taxdetails&id=109745 on 2025-05-13
Nozères, C., Kennedy, M.K. (Eds.) (2025). Canadian Register of Marine Species. Amphidinium operculatum Claparède & Lachmann, 1859. Accessed at: https://www.marinespecies.org/carms/aphia.php?p=taxdetails&id=109745 on 2025-05-13
taxonomy sourceS. Murray, M. Flø Jørgensen, N. Daugbjerg & L. Rhodes (2004) Amphidinium revisited. II. Resolving species boundaries in the Amphidinium operculatum species complex (Dinophyceae), including the descriptions of Amphidinium trulla sp. nov. and Amphidinium gibbosum comb. nov. J. Phycol. 40: 366-382.[details]
basis of recordGómez, F. (2005). A list of free-living dinoflagellate species in the world's oceans. Acta Bot. Croat. 64(1): 129-212.[details]
additional sourceGuiry, M.D. & Guiry, G.M. (2025). AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. searched on YYYY-MM-DD., available online athttp://www.algaebase.org[details]
additional sourceBrandt, S. (2001). Dinoflagellates, in: Costello, M.J. et al. (Ed.) (2001). European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels, 50: pp. 47-53 (look up in IMIS) [details]
additional sourceMoestrup, Ø., Akselman, R., Cronberg, G., Elbraechter, M., Fraga, S., Halim, Y., Hansen, G., Hoppenrath, M., Larsen, J., Lundholm, N., Nguyen, L. N., Zingone, A. (Eds) (2009 onwards). IOC-UNESCO Taxonomic Reference List of Harmful Micro Algae., available online athttp://www.marinespecies.org/HAB[details]
additional sourceYasumoto T., Seino N., Murakami Y. & Murata M. 1987. Toxins produced by benthic dinoflagellates. Biol. Bull. 172: 128-131.[details]
additional sourceSteidinger, K. A., M. A. Faust, and D. U. Hernández-Becerril. 2009. Dinoflagellates (Dinoflagellata) of the Gulf of Mexico, Pp. 131–154 in Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Biodiversity. Texas A&M Press, College[details]
redescriptionFlø Jørgensen, M.; Murray, S.; Daugbjerg, N. (2004). Amphidinium revisited. I. Redefinition of Amphidinium (Dinophyceae) based on cladistic and molecular phylogenetic analyses. J. Phycol. 40: 351-365.[details]
Description Cells ovoid, dorsoventrally flattened. Epicone 7–10 μm wide, anteriorly flat, with the right anterior corner ~ 90°, the left corner extended, approx 30–45°. Cingulum beginning 0.2–0.3 of the cell length from the apex, initially ascending, continuing almost horizontally around the cell; proximal end slightly higher than distal. Hypocone rounded, slightly asymmetrical. Sulcus initially narrow, widening at the posterior end. Apical groove absent. A narrow ventral ridge running between the two points of flagellar insertion. Two pusules present: one obvious, c. 2 μm diam., to the right of the origin of the sulcus; the second less obvious, also c. 2 μm diam., just below and to the left of the proximal end of the cingulum. Nucleus in the posterior part of the hypocone, crescent-shaped or oval, containing very fine chromosomes. One orange-yellow, round, globular inclusion, possibly an eyespot, diameter 6–8 μm. Division by binary fission in the motile cell. [details] Harmful effect Compounds with haemolytic and antifungal properties (amphidinols) known. May also be toxic to fish. [details]
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