Akashiwo sanguinea

Super Group: 
(K.Hirasaka) G.Hansen & Ø.Moestrup
Gymnodinium sanguineum K.Hirasaka.
Gymnodinium splendens Lebour
Gymnodinium nelsonii Martin


Diagnosis_Genus: Akashiwo G. Hansen & Moestrup. Unarmoured dinoflagellates with chloroplasts containing peridinin as major carotenoid. Nuclear envelope of typical eukaryotic apparearance (i.e. lacking envelope chambers). Dorsal connective between the flagellar apparatus and the nucleus absent. Apical groove curves around the apex in a clockwise direction.
Diagnosis_Species: A. sanguinea G. Hansen & Moestrup. The cell has a large number of elongate yellow or brown chloroplasts that radiate from the cell center. The nucleus is just above the cingulum in the epicone, and distinguishable in living cells by appearing as a clear area. The trailing flagellum is quite long, often longer than the cell itself. Akashiwo sanguinea is exclusively planktonic and has a worldwide distribution in temperate and tropical waters.  It is nearly always found in coastal and estuarine locations. This species is a cosmopolitan red tide former that has been associated with fish and shellfish mortality events. This species is highly variable in size and shape. Cells are large, slightly dorso-ventrally flattened and roughly pentagonal. An apical groove is present. The epitheca and hypotheca are nearly equal in size. The epitheca is rounded and conical, and the hypotheca is deeply intended by the sulcus creating two posterior lobes. The median cingulum is left-handed and displaced 1-2 times its width. The sulcus does not invade the epitheca, but expands posteriorly into the hypotheca. This species has numerous large, spnidle-shaped, reddish-yellow-brown chloroplasts radiating from the center of the cell. The large nucleus is slightly off-center. Cells can vary from heavily pigmented to pale yellow or nearly colorless. 

Body_length: 40-80 µm
Toxicity: No
Bloom: Yes (Daugbjerg et al. 2000)


akashiwo (Japanese)= red tide. Sanguinea=Adjective (Latin), blood-red (Stearn 1973), describing the resulting color of the water after a red tide event.

Type species

This is the type species (holotype) of the genus Akashiwo.

Type illustration / Type locality / Type specimen

Type locality: NW Pacific Ocean: Kozusa-ura, Gokasho Bay, Japan (Faust & Gulledge 2002: 43). Holotype: (Faust & Gulledge 2002: 43).


Substrate: planktonic
Sociability: solitary
Salinity: marine
Salinity:variable (estuary)
pH: neutral
Feeding: photosynthetic
Feeding: predatory. Preys on ciliate, Bockstahler & Coats 1993. See also Jeong et al. (2005).

Life cycle

Phases_alternance: haplontic
Generation: <1 month

Feeding behaviour


Mode of locomotion

Two flagella typical for Dinophyceae
Flagellum: 2
Motility: motile_swimming

Attached phylogeny

Observation site(s)


Displaying 1 - 8 of 8
Association with... Region origin Name of site In reference...
Amoebophrya ceratii-species complex Santa Cruz Wharf - Monterey Bay
Amoebophrya ceratii-Clade-3 Chesapeake Bay
Coats WD, Bockstahler KR (1994) Occurrence of the Parasitic Dinoflagellate Amoebophrya ceratii in Chesapeake Bay Populations of Gymnodinium sanguineum. The Journal of Eukaryotic Microbiology 41:586 - 593. doi: 10.1111/jeu.1994.41.issue-610.1111/j.1550-7408.1994.tb01520.x
Amoebophrya ceratii-Clade-3 Chesapeake Bay
Amoebophrya ceratii-Clade-3 Chesapeake Bay - Rhode river
Parvilucifera infectans Penzé estuary
Parvilucifera infectans Rance estuary
Parvilucifera rostrata Penzé estuary
Parvilucifera sp. Catalunya Harbor of Tarragona