Baltisphaeridium oligacanthum ssp. granulatum, (W. Wetzel, 1952), Downie and Sarjeant, 1965

Now Surculosphaeridium? granulatum. Originally Hystrichosphaeridium oligacanthum ssp. granulatum, subsequently Baltisphaeridium oligacanthum ssp. granulatum, thirdly Cleistosphaeridium? oligacanthum ssp. granulatum, fourthly (and now) Surculosphaeridium? granulatum.

Holotype: W. Wetzel, 1952, text-fig.25; Sarjeant, 1984, pl.5, figs.1-3; text-fig.8
Age: Paleocene