Isabelidinium extremum

?extremum (Cookson and Eisenack, 1974, p.48, pl.20, fig.4) Stover and Evitt, 1978, p.109.  Holotype: Cookson and Eisenack, 1974, pl.20, fig.4.  Originally Deflandrea, subsequently Spongodinium?, thirdly (and now) Isabelidinium?.  Questionable assignment: Stover and Evitt (1978, p.109).  Age: Albian-Cenomanian.

Parent: Isabelidinium