Spiniferites membranosus
From dinoflaj2
"membranosus" (Archangelsky, 1969b, p.197,199, pl.3, figs.1-4) Lentin and Williams, 1973, p.128. Holotype: Archangelsky, 1969b, pl.3, figs.1-3. Originally Hystrichosphaera, subsequently (and now) Spiniferites. Taxonomic senior synonym: Hystrichosphaera (as and now Achomosphaera) crassipellis, according to Quattrocchio and Sarjeant (1996, p.116). Age: Late Eocene.
Parent: Spiniferites