Palaeotetradinium paucispinum (Alberti, 1961) Stover and Evitt, 1978

Now Rhombodella. Originally Palaeohystrichophora, subsequently Palaeotetradinium, thirdly (and now) Rhombodella.
Tax. sr. synonym of Rhombodella natans Cookson and Eisenack, 1962, according to Stover and Evitt, 1978. Lentin and Williams, 1981 retained this species in Rhombodella Cookson and Eisenack, 1962.
Holotype: Alberti, 1961, pl.3, fig.25
Locus typicus: Haverlahwiese, Salzgitter, Germany
Stratum typicum: Albian
Translation Alberti, 1961: LPP

Original diagnosis: Alberti, 1961, p. 19: Palaeohystrichophora paucispina
Shell flattened, elongate biconical. Apex and antapex slightly blunted. Epi- and hypotheca of nearly equal size. Girdle as well as longitudinal furrow indicated by parallel, interrupted lines. The longitudinal furrow extends from the mid-epitheca to the antapex. Cyst with few, short, solid, slightly curved thorns, which appear at the poles and the flanks of the body in height of the girdle. Thorns 4-5 µm long. No inner body has been observed.

Affinities:
Alberti, 1961, p.20: Palaeohystrichophora paucispina
P. paucispina differs from all other species in having short, solid thorns.