Palaeoperidinium ellipsoideum Deflandre, 1936

Now Microdinium?. Originally Palaeoperidinium, subsequently (and now) Microdinium?. Stover and Evitt, 1978 considered this to be a "problematical species" of Palaeoperidinium.
Holotype: Deflandre, 1936, pl.6, figs.6-7
Age: Senonian