Microdinium singulare Vozzhennikova, 1967

Originally (and now) Microdinium, subsequently Microdinium?.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Microdinium.
Lentin and Vozzhennikova, 1990, included the species in Microdinium without question.
Below, 1987, considered this species to be a nomen dubium.

Holotype: Vozzhennikova, 1967, pl.39, figs.2a-b; Lentin and Vozzhennikova, 1990, text-fig.63 (lost, according to Lentin and Vozzhennikova, 1990)
Lectotype: none available, according to Lentin and Vozzhennikova, 1990
Locus typicus: Laryak, W. Siberia
Stratum typicum: Eocene

Original diagnosis: Vozzhennikova, 1967, p.93
Theca broadly ovoicl, epitheca much smaller than hypotheca. Arrangement of plates and furrows as in type, plates and transverse furrow bordered with low, narrow, smooth crests, Plates covered with short tubercles which lie in the middle of the plates or parallel with the processes. Transverse furrow broad.
Dimensions: Holotype- length 31.1 Ám, breadth 27.6 Ám, width of transverse furrow 4.5 Ám.