Hystrichosphaeridium microtriainum
From dinoflaj3
"microtriainum" Klumpp, 1953, p.390, pl.17, figs.6–7. Emendation: Sarjeant, 1981, p.110–112, as Achomosphaera microtriaina. Holotype: Klumpp, 1953, pl.17, figs.6–7; Sarjeant, 1981, pl.2, figs.1–2; text-fig.2. NOW Operculodinium. Originally Hystrichosphaeridium, subsequently Cordosphaeridium, thirdly Cordosphaeridium?, fourthly Polysphaeridium, fifthly Achomosphaera, sixthly (and now) Operculodinium. Age: late Eocene.
Parent: Hystrichosphaeridium