From Fensome et al., 2019:
Palaeohystrichodinium quadratum He Chengquan, Zhu Shenzhao and Jin Guangxing in He Chengquan et al., 1989, p.57, pl.16, figs.1–3.
Holotype: He Chengquan et al., 1989, pl.16, fig.1. Age: early Tertiary.

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