Cleistosphaeridium williamsii

"?williamsii" (Boltenhagen, 1977, p.41–42, pl.2, figs.6–7) Lentin and Williams, 1981, p.51.  Holotype: Boltenhagen, 1977, pl.2, fig.6; Fauconnier and Masure, 2004, pl.50, fig.6.  NOW Impletosphaeridium.  Originally Polysphaeridium, subsequently Cleistosphaeridium?, thirdly (and now) Impletosphaeridium.  Questionable assignment: Lentin and Williams (1981, p.51).  Age: Cenomanian–early Turonian.

Parent: Cleistosphaeridium