Rhombodinium glabrum subsp. crassithecum

"subsp. crassithecum" (Vozzhennikova, 1967, p.170, pl.91, figs.1–2,4–6) Lentin and Williams, 1973, p.120.  Holotype: Vozzhennikova, 1967, pl.91, fig.1; Lentin and Vozzhennikova, 1990, text-fig.40; lost according to Lentin and Vozzhennikova (1990, p.76).  NOW Petalodinium crassithecum.  Originally Rhombodinium glabrum forma crassithecum, subsequently Rhombodinium glabrum subsp. crassithecum, thirdly (and now) Petalodinium crassithecum.  According to Lentin and Vozzhennikova (1990, p.76), no potential lectotype is available.  These authors recommended that this name be restricted to the type.  Age: late Eocene–early Oligocene.

Parent: Rhombodinium glabrum