Gymnodinium sibiricum Vozzhennikova, 1967; Emendation: Lentin and Vozzhennikova, 1990, p.21-22, as Dinogymnium sibiricum.

Now Dinogymnium. Originally Gymnodinium, subsequently (and now) Dinogymnium.
This species was a nomen nudum in Vozzhennikova, 1963, who did not provide a description.

Holotype: Vozzhennikova, 1967, pl.3, figs.2-3; Lentin and Vozzhennikova, 1990, text-fig.8 (lost according to Lentin and Vozzhennikova, 1990)
Lectotype: Vozzhennikova, 1967, pl.2. fig.2 (designated by Lentin and Vozzhennikova, 1990)
Locus typicus: Yuzhno-Kolpashevsk area, W Sibiria
Stratum typicum: Senonian
Translation Vozzhennikova, 1967: Lees in Sarjeant, 1971, p. 69-70

Original description: Vozzhennikova, 1967, p. 47-48
Theca biconical. Ephitheca smaller than hypotheca, helmet-shaped, bluntly rounded at the apex. Hypotheca conical with curved sides and bluntly rounded antapex. Transverse furrow deep, annulate, its ends extending to the ventral expansion of the longitudinal furrow. The longitudinal furrow only extends a short distance onto the epitheca and hypotheca. Theca finely dotted with numerous thin longitudinal ribs which are sometimes joined together in pairs and which run from the transverse furrow towards the apical and antapical ends.
Dimensions: Holotype: length 67.6 Ám, breadth 37.8 Ám, length of epitheca 24.3 Ám, length of hypotheca 43.5 Ám, width of transverse furrow 3.0 Ám. In other specimens the length is 67.5-65.6 Ám, breadth 37.8-37.5 Ám, length of epitheca 21.6 Ám, length of hypotheca 45.9 Ám and width of transverse furrow 4.5-3.5 Ám.

Affinities:
Vozzhennikova, 1967, p. 49: This species is similar to Gymnodinium curvatum the latter however having a more attenuated and cuved hyptheca.