Petalodinium rhomboideum (Alberti, 1961, p.10, pl.1, figs.1–5; pl.12, fig.9) Williams et al., 2015, p.308.

Originally Wetzeliella subgenus Rhombodinium, subsequently Rhombodinium, thirdly Dracodinium, fourthly (and now) Petalodinium.

Holotype: Alberti, 1961, pl.1, fig.3; pl.12, fig.9.
Age: late Eocene.