Palaeoperidinium "?asperum" Xu Jinli, 1987, p.153, pl.4, figs.11–12. Holotype: Xu Jinli, 1987, pl.4, fig.11. Questionable assignment: Evitt et al. (1998, p.48). Taxonomic senior synonym: Palaeoperidinium angularium, according to He Chengquan et al. (2009, p.399). Age: ?middle-late Eocene.