Impagidinium brevisulcatum
From dinoflaj3
"brevisulcatum" Michoux, 1985, p.144–145, pl.1, figs.9–11; text-fig.4. Holotype: Michoux, 1985, pl.1, fig.10; Jan du Chêne et al., 1986a, pl.56, figs.4–6. NOW Ynezidinium. Originally Impagidinium, subsequently (and now) Ynezidinium. Age: middle Eocene.