Pareodinia ceratophora ssp. pachyceras (Sarjeant, 1959) Lentin and Williams, 1973

Originally Pareodinia ceratophora var. pachyceras, subsequently Pareodinia ceratophora ssp. pachyceras.
Tax. jr. synonym of Pareodinia ceratophora var. ceratophora, the autonym, according to Below, 1990. Sarjeant, 1976 retained this taxon as a varietas; however, Lentin and Williams, 1989 retained it as a subspecies of Pareodinia ceratophora Deflandre, 1947.
Holotype: Sarjeant, 1959, pl.13, fig.10; text-fig. 5a
Locus typicus: Yorkshire, Cayton Bay, below High Red Cliff
Stratum typicum: Early Callovian

Original diagnosis: Sarjeant, 1959, p.337
A variety of Pareodinia ceratophora with the terminal horn blunt and strong, not tapering.

Original description: Sarjeant, 1959, p.337
Theca of subspherical to oval form with a rounded apex from which arises a strong, blunt horn. The horn is hollow; its length is about one-third to one-half of the body. The membrane is brownish-yellow in colour, moderately thick and with a faintly granular surface.

Dimensions:
Holotype: Overall length 59 µm, maximum breadth 33 µm, length of horn 18 µm, breadth of horn around 6 µm. Range: overall length 55 to 65 µm.