Cleistosphaeridium spiralisetum
From dinoflaj2
"?spiralisetum" (de Wit, 1943, p.383; text-figs.2,11) Davey et al., 1969, p.16. Holotype: de Wit, 1943; text-figs.2,11, lost according to R. de Wit (personal communication to G.L.W.). NOW Impletosphaeridium?. Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Appendix A), thirdly Cleistosphaeridium, fourthly (and now) Impletosphaeridium?. Questionable assignment: Davey et al. (1969, p.16). This combination was not validly published in Davey et al. (1966, p.170), since these authors did not fully reference the basionym. Age: Late Cretaceous.
Parent: Cleistosphaeridium