Hystrichosphaeridium palmatum Deflandre and Courteville, 1939

Now Exochosphaeridium?. Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Exochosphaeridium, fourthly Exochosphaeridium?.
Sr. homonym of Hystrichosphaeridium palmatum (White, 1842) Downie and Sarjeant, 1965.
Tax. jr. synonym (as Exochosphaeridium palmatum) of Pervosphaeridium pseudhystrichodinium (Deflandre, 1937) Yun, 1981, according to Yun, 1981.
Holotype: Deflandre and Courteville, 1939, pl.3, fig.1
Age: Late Cretaceous