Phthanoperidinium diamantum

"?diamantum" (Churchill and Sarjeant, 1962, p.34-36, pl.1, fig.19; text-fig.3) Lentin and Williams, 1973, p.113.  Holotype: Churchill and Sarjeant, 1962, pl.1, fig.19; text-fig.3.  NOW Gonyaulacysta.  Originally Peridinium? (Appendix B), subsequently Phthanoperidinium?, thirdly (and now) Gonyaulacysta.  Questionable assignment: Lentin and Williams (1973, p.113).  Age: Holocene.

Parent: Phthanoperidinium