Membranosphaera bulluliniformis ssp. sphaerica (Maliavkina in Samoilovitch and Mtchedlishvili, 1961) Lentin and Williams, 1973

Originally Membranosphaera bulluliniformis forma sphaerica, subsequently (and now) Membranosphaera bulluliniformis ssp. sphaerica.
Holotype: Samoilovitch and Mtchedlishvili, 1961, pl.84, fig.4
Age: Middle Oxfordian-Middle Valanginian