From Fensome et al., 2019:
Downiesphaeridium bulbum (Yu Jingxian, 1989, p.140, pl.51, figs.8–9) Williams et al., 1998, p.203. Holotype: Yu Jingxian, 1989, pl.51, fig.8. Originally Cleistosphaeridium, subsequently Downiesphaeridium, thirdly (and now) Downiesphaeridium?. Questionable assignment: Masure in Fauconnier and Masure (2004, p.196). Age: Eocene.

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