Cleistosphaeridium panniforme, (Gerlach, 1961, p.196-198, pl.28, fig.13), Stover and Evitt, 1978, p.31.

NOW Impletosphaeridium. Originally Baltisphaeridium, subsequently (and now) Impletosphaeridium, thirdly Cleistosphaeridium. Taxonomic senior synonym: Hystrichosphaeridium (now Cleistosphaeridium) placacanthum, according to Sarjeant (1984b, p.86-87) - however, Eaton et al. (2001, p.191) retained Baltisphaeridium (as and now Impletosphaeridium) panniforme.

Holotype: Gerlach, 1961, pl.28, fig.13.
Age: mid Oligocene.