From Fensome et al., 2019:
Adnatosphaeridium? huenickenii, Archangelsky, 1969b, p.201,203, pl.5, figs.5–7.
Holotype: Archangelsky, 1969b, pl.5, figs.5–6.
Originally Adnatosphaeridium, subsequently (and now) Adnatosphaeridium?. Questionable assignment: Stover and Evitt (1978, p.15), as a problematic species.
Age: Eocene.

Locus typicus: Rio Turbia Formation, SW of province Santa Cruz, Argentina

---------------------------------------------------------------------------------------------------

Original description: [Arachangelsky, 1969, p. 201] (Translation: LPP):

Diagnosis:
Ellipsoidal, sometimes sphaerical cyst with two-layered wall and apical archaeopyle. Inner Layer smooth, outer layer (periphragm) with furcate processes which may be connected by trabeculae that may be developed as membranes with fenestrae of varying size. Process bases free, not connected by ridges. Periphragm relatively thick (2-3 µm), microreticulate with papillae.

Dimensions:
Holotype: 54x54 µm, archaeopyle 31 µm, processes 14 µm.
Range: Length 48-67 µm, breadth 35-64 µm, archaeopyle 17-31 µm, processes 11-14 µm.