Hystrichosphaeridium spiralisetum

"spiralisetum" de Wit, 1943, p.383; text-figs.2,11.  Holotype: de Wit, 1943, text-figs.2,11, lost according to de Wit (personal communication to GLW).  NOW Impletosphaeridium?.  Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Appendix A), thirdly Cleistosphaeridium?, fourthly (and now) Impletosphaeridium?.  Age: Late Cretaceous.

Parent: Hystrichosphaeridium