From Fensome et al., 2019:
Phthanoperidinium tenellum Jin Guangxing, He Chengquan and Zhu Shenzhao in He Chengquan et al., 1989, p.62–63, pl.6, fig.22. Holotype: He Chengquan et al., 1989, pl.6, fig.22. Age: early Tertiary.

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