Palaeoperidinium piriforme

"?piriforme" Conrad, 1941, p.9, pl.1, fig.G.  Holotype: Conrad, 1941, pl.1, fig.G.  Name not validly published: generic name not validly published until 1967.  NOW Gonyaulacysta.  Originally Palaeoperidinium (name not validly published), subsequently Gonyaulacysta? (combination not validly published), thirdly (and now) Gonyaulacysta, fourthly Palaeoperidinium? (combination not validly published).  Questionable assignment: Stover and Evitt (1978, p.218) as a problematic species.  This combination was not validly published in Stover and Evitt (1978, p.218) since these authors did not fully reference the basionym.  Age: Maastrichtian.

Parent: Palaeoperidinium