''Gymnodinium'' is a genus of

dinoflagellate The Dinoflagellates (), also called Dinophytes, are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered protists. Dinoflagellates are mostly marine plankton, but they are also commo ...

s, a type of marine and freshwater

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

. It is one of the few naked dinoflagellates, or species lacking armor known as cellulosic plates. Since 2000, the species which had been considered to be part of ''Gymnodinium'' have been divided into several genera, based on the nature of the apical groove and partial LSU rDNA sequence data. ''

Amphidinium ''Amphidinium'' is a genus of dinoflagellates. The type for the genus is '' Amphidinium operculatum'' Claparède & Lachmann. The genus includes the species '' Amphidinium carterae'' which is used as a model organism. As dinoflagellates, ''Amphid ...

'' was redefined later. Gymnodinium belong to red dinoflagellates that, in concentration, can cause

red tide A harmful algal bloom (HAB), or excessive algae growth, sometimes called a red tide in marine environments, is an algal bloom that causes negative impacts to other organisms by production of natural algae-produced toxins, water deoxygenation, ...

s. The red tides produced by some ''Gymnodinium'', such as '' Gymnodinium catenatum'', are toxic and pose risks to marine and human life, including

paralytic shellfish poisoning Paralytic shellfish poisoning (PSP) is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks (such as mussels, clams, oysters and scallops). These shellfi ...

Segregate genera

*''Gymnodinium''

sensu stricto ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular c ...

*'' Akashiwo'' *''

'' *''

Gyrodinium ''Gyrodinium'' is a genus of dinoflagellates belonging to the order Gymnodiniales within class Dinophyceae. The genus has cosmopolitan distribution. World Register of Marine Species lists 141 species, with many synonyms. They are heterotrophic ...

'' *'' Karenia'' *''

Karlodinium ''Karlodinium'' is a genus of athecate dinoflagellates that lives worldwide. They are often toxin producing, and compared to the other members of the Kareniaceae, are fairly small at <8-15 μm diameter. They are also able to form intense

'' *''

Katodinium ''Katodinium'' is a genus of dinoflagellates belonging to the family Tovelliaceae. The genus was first described by Fott in 1957. Species * ''Katodinium asymmetricum'' (Massart) A.R.Loeblich, III, 1965 * ''Katodinium galeatum'' (W.Conrad) A.R ...

Former species

Torodinium ''Torodinium'' (ˌtɔɹoʊˈdɪniəm) is a genus of unarmored dinoflagellates and comprises two species, ''Torodinium robustum'' and the type species ''Torodinium teredo''.Kofoid, C.A. and Swezy, O. 1921: The free-living unarmored dinoflagellate ...

'' (with ''Torodinium robustum'' and the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

''Torodinium teredo'') were both formerly ''Gymnodinium teredo'' until 1921. Kofoid, C.A. and Swezy, O. 1921: The free-living unarmored dinoflagellate. University of California Press, Berkeley, California, USA

Segregate genera

Former species

References

Further reading