Home / Dinophyceae /Photosynthetic / Gymnodinium

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Name derivation:

From the Greek gymnos, naked, and dineo, to whirl, in reference to the very thin thecal plates that give the cell the appearance of being unarmored, and to the cell's whirling motion due to one flagellum (of two) that encircles the groove and provides rotary thrust. The other flagellum trails and pushed the cell.


Gymnodinium Stein, 1878;  297 of 468 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013).

Order Dinotrichales;  Family Dinotrichaceae


Thin thecal plates make the cell appear unarmored. The epicone and hypocone are about the same size.

G. acidotum contains a photosynthetic endosymbiotic cryptomonad (Wilcox and Wedemayer 1984).

Similar genera:

Woloszynskia has slightly thicker plates that can be observed under the microscope.


Most are marine, but several important species occur in freshwater.



Guiry, M.D. & Guiry, G.M. 2013.  AlgaeBase. World-wide electronic publication, National University of Ireland, Galway.  http://www.algaebase.org; searched on 8 November 2013.

Stein, F. von  1878.  Der Organismus der Infusionsthiere. III. Flagellaten I. pp. 1-154. Leipzig: Engelmann.

Wilcox, L.W. and G.J. Wedemayer  1984.  Gymnodinium acidotum Nygaard (Pyrrophyta), a dinoflagellate with an endosymbiotic cryptomonad.  Journal pf Phycology 20:236-242.