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Karenia mikimotoi (Miyake & Kominami ex Oda) Gert Hansen & Moestrup 2000

Empire Eukaryota
Kingdom Chromista
Subkingdom Harosa (supergroup SAR)
Infrakingdom Halvaria
Phylum Miozoa
Subphylum Myzozoa
Infraphylum Dinozoa
Superclass Dinoflagellata
Class Dinophyceae
Order Gymnodiniales
Family Kareniaceae
Genus Karenia


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Karenia mikimotoi (Miyake & Kominami ex Oda) Gert Hansen & Moestrup
Ireland.. Caroline Cusack. © Caroline Cusack (robin.raine@nuigalway.ie).

Karenia mikimotoi (Miyake & Kominami ex Oda) Gert Hansen & Moestrup
Ireland. Robin Raine. © Robin Raine (Robin.Raine@nuigalway.ie).


Karenia mikimotoi (Miyake & Kominami ex Oda) Gert Hansen & Moestrup Ireland
© Robin Raine (Robin.Raine@nuigalway.ie)

Publication details
Karenia mikimotoi (Miyake & Kominami ex Oda) Gert Hansen & Moestrup in N. Daugbjerg, G. Hansen, J. Larsen, & Ø. Moestrup 2000: 308

Published in: Daugbjerg, N., Hansen, G., Larsen, J. & Moestrup, Ø. (2000). Phylogeny of some of the major genera of dinoflagellates based on ultrastructure and partial LSU rDNA sequence data, including the erection of three new genera of unarmoured dinoflagellates. Phycologia 39: 302-317.
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Type species
The type species (holotype) of the genus Karenia is Karenia brevis (C.C.Davis) Gert Hansen & Moestrup.

Status of name
This name is of an entity that is currently accepted taxonomically.

Gymnodinium mikimotoi Miyake & Kominami ex Oda

Type information
Type locality: NW Pacific Ocean: Gokasho Bay, Japan (Faust & Gulledge 2002: 40). Holotype: (Faust & Gulledge 2002: 40).

Homotypic Synonym(s)
Gymnodinium mikimotoi Miyake & Kominami ex Oda 1935

Heterotypic Synonym(s)
Gymnodinium nagasakiense H.Takayama & M.Adachi 1985

Usage notes
First described from Japan in 1935, this species was found in the Atlantic in 1957 on the east coast of the USA, and, in 1966, it bloomed off the coast of Norway. It appears to have been spread in ballast water and is now a major cause of algal blooms throughout the world. A major bloom took place in the English Channel in 2003. It was first found in Irish waters in 1976, and it bloomed in successive years from 1978 and 1982, and again from 1990 to 1995. In 2005, a enormous bloom off the west coast of Ireland covered many hundreds of square kilometers of coastal waters and caused major 'kills' of marine organisms including fish, shellfish, brittle stars, and farmed salmon and cod. The "Irish Times" of August 6, 2005 quoted Kevin Flannery, Sea Fisheries Officer with the Department of the Marine: "We are now talking about huge marine dead zones." Harmful species (Lassus et al. 2017).

General environment
This is a marine species.

A photosynthetic species with several oval to round yellow-brown chloroplasts, each with a pyrenoid. The large ellipsoidal nucleus is located in the left hypothecal lobe. No thecal plates are present. Cells are small, broadly oval to almost round and compressed dorso-ventrally. Cells are slightly longer than wide with a characteristic long and straight apical groove to the right of the sulcal axis. The apical groove extends from the ventral side to the dorsal side of the epitheca creating a slight indentation at the apex of the cell. Cells range in size from 18-40 µm in length to 14-35 µm in width .The epitheca is broadly rounded and smaller than the hypotheca. The hypotheca is notched by the widening sulcus at the antapex resulting in a lobed posterior. The wide and deeply excavated cingulum is pre-median, and is displaced in a descending spiral about 2 times its width. The sulcus slightly invades the epitheca extending from above the cingulum to the antapex (adapted from http://www.nmnh.si.edu/botany/projects/dinoflag/Taxa/Gmikimotoi.htm).

A planktonic species first described from western Japan. This species is a recurring bloom former in coastal waters of Japan and Korea; red tides commonly occur in warmer months and are associated with massive fish and shellfish kills. Reported to be eurythermal and euryhaline, populations of G. mikimotoi could presumably over-winter as motile cells, which could then serve as seed populations for a summer red tide. Moreover, studies conducted in Omura Bay, Japan, revealed that this species can tolerate anoxic or near anoxic conditions utilizing sulfide from the sediment.

Key characteristics
Cells have a distinct swimming pattern: turning over through water, like a falling leaf.

Detailed distribution with sources (Click to Load)

Key references
Escobar-Morales, S. & Hernández-Becerril, D.U. (2015). Free-living marine planktonic unarmoured dinoflagellates from the Gulf of Mexico and the Mexican Pacific. Botanica Marina 58(1): 9-22.

Hallegraeff, G.M., Anderson, D.M. & Cembella, A.D., Eds (2003). Manual on harmful marine microalgae. Paris: UNESCO.

Larsen, J. & Nguyen-Ngoc, L. [eds.] (2004). Potentially toxic microalgae of Vietnamese waters. Opera Botanica 140: 5-216. [in English and Vietnamese]

Lassus, P., Chomérat, N., Hess, P. & Nézan, E. (2017 '2016'). Toxic and harmful microalgae of the World Ocean. Micro-algues toxiques et nuisibles de l'Océan Mondial. IOC Manuals and guides, 68 (Bilingual English/French). pp. 1-523, 54 pls. Denmark: International Society for the Study of Harmful Algae/ Intergovernmental Oceanographic Commission of UNESCO.

Lindberg, K., Moestrup, Ø & Daugbjerg, N. (2005). Studies on woloszynskioid dinoflagellates I: Woloszynskia coronata re-examined using light and electron microscopy and partial LSU rDNA sequences, with description of Tovellia gen. nov. and Jadwigia gen. nov. (Tovelliaceae fam. nov.). Phycologia 44: 416-440.

Ryan, D.E. & Campbell, L. (2016). Identification and phylogeny of putative PEPC genes in three toxin-producing Karenia (Dinophyta) species. Journal of Phycology 52(4): 618-625.

Created: 26 April 2002 by M.D. Guiry

Verified by: 24 April 2018 by M.D. Guiry

Accesses: This record has been accessed by users 7361 times since it was created.

Verification of data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.

(Please note: only references with the binomials in the title are included. The information is from the Literature database.)

Kim, D., Wencheng, L., Matsuyama, Y., Cho, K., Yamasaki, Y., Takeshita, S., Yamaguchi, K. & Oda, T. (2019). Extremely high level of reactive oxygen species (ROS) production in a newly isolated strain of the dinoflagellate Karenia mikimotoi. European Journal of Phycology 54(4): 632-640.
Leblond, J.D., McDaniel, S.L., Lowrie, S.D., Khadka, M. & Dahmen, J. (2019). Mono- and digalactosildiacyglycerol composition of dinoflagelltes. VIII. Temperature effects and a perspective on the curious case of Karenia mikimotoi as a producer of the unusual, 'green algal' fatty acid hexadecatetraenoic acid [16:4(n-3)]. European Journal of Phycology 54(1): 78-90.
Liu, Y., Hu, Z., Deng, Y. & Tang, Y.Z. (2019). Evidence for production of sexual resting cysts by the toxic dinoflagellate Karenia mikimotoi in clonal cultures and marine sediments. Journal of Phycology 56(1): 121-134.
Yuasa, K., Shikata, T., Kuwahara, Y. & Nishiyama, Y. (2018). Adverse effects of strong light and nitrogen deficiency on cell viability, photosynthesis, and motility of the red-tide dinoflagellate Karenia mikimotoi. Phycologia 57(5): 525-533.

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Citing AlgaeBase
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 16 June 2021.

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