From Fensome et al., 2019:
Alterbidinium compactum, Vasilyeva in Andreeva-Grigorovich et al., 2011, p.40–42, pl.11, figs. 1–4; text-fig. 18a ex Williams and Fensome, 2016, p.138.
Holotype: Andreeva-Grigorovich et al., 2011, text-fig.18a, pl.11, fig.1, designated by Williams and Fensome (2016, p.138). This name was not validly published by Vasilyeva in Andreeva-Grigorovich et al. (2011, p.41) since the holotype citation (pl.11, figs.1–4 and text-fig.18a) includes more than one specimen. The holotype was clearly designated in Williams and Fensome (2016), thus validating the name Alterbidinium compactum.
Age: Selandian.

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