From Fensome et al., 2019:
Impletosphaeridium commixtum (Jiabo, 1978, p.61–62, pl.21, figs.3–5) Islam, 1993, p.85–86. Holotype: Jiabo, 1978, pl.21, fig.3.
Originally Cleistosphaeridium, subsequently (and now) Impletosphaeridium. Age: early Tertiary.

---------------------------------------------------------------------------------------------------