Xanthidium spinosum Appendix A

"spinosum" White, 1842, p.37, pl.4, fig.6.  Holotype: White, 1842, pl.4, fig.6; lost according to Sarjeant (1966b, p.141).  NOW Exochosphaeridium?.  Originally Xanthidium, subsequently Hystrichosphaeridium, thirdly Baltisphaeridium (Appendix A), fourthly Cordosphaeridium (combination not validly published), fifthly Exochosphaeridium, sixthly (and now) Exochosphaeridium?.  Age: Late Cretaceous.

Parent: Xanthidium_Appendix A