Gonyaulax edwardsii Cookson and Eisenack 1958

Now Cribroperidinium. Originally Gonyaulax, subsequently Gonyaulacysta, thirdly (and now) Cribroperidinium.
Taxonomic junior synonyms: Gonyaulax (as Cribroperidinium) apione, according to Burger (1980a, p.82) — however, Jan du Chêne et al. (1986a, p.76) retained Cribroperidinium apione; and Gonyaulax (as Cribroperidinium) orthoceras, according to Davey and Verdier (1971, p.17) — however, Lentin and Williams (1985, p.79) retained Gonyaulax (as Cribroperidinium) orthoceras.

Holotype: Cookson and Eisenack 1958, pl.3, fig.6, text-fig.7; Jan du Chêne et al., 1986, pl.32, fig.4; pl.33, fig.3
Paratypes: Cookson and Eisenack, 1958
Locus typicus: Carnarvon Basin, W-Australia
Stratum typicum: Albian-Early Turonian

Original description: Cookson and Eisenack, 1958, p.32-33
Shell nearly sphaerical, thick walled. Epitheca with a long, stiff, pointed and sometimes curved horn. Girdle helicoid, narrow with low borders; longitudinal furrow broad. Plates finely granular, the inner surface of girdle sometimes more coarsely granular than plates. Sutures of the plates with low, thin ledges which often bear a few rather broad, pointed spines especially in the apical and antapical regions.
Dimensions: Type 143x125 µm overall.