From Fensome et al., 2019:
Impletosphaeridium minus (Jiabo, 1978, p.62, pl.20, figs.13–16) Islam, 1993, p.86. Holotype: Jiabo, 1978, pl.20, fig.16. Originally Cleistosphaeridium, subsequently (and now) Impletosphaeridium. Age: early Tertiary.

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