From Fensome et al., 2019:
Achomosphaera mariannae, (Philippot, 1949, p.56–57; text-fig.2) Stover and Evitt, 1978, p.139.
Holotype: Philippot, 1949, text-fig.2.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Appendix A), thirdly (and now) Achomosphaera.
Age: Late Cretaceous.

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