From Fensome et al., 2019:
Canningia minor ssp. psilata (Burger, 1980a, p.71, pl.25, figs.5–11) Lentin and Williams, 1981, p.33. Holotype: Burger, 1980a, pl.25, fig.10. Originally Canningia? minor var. psilata, subsequently Canningia? minor subsp. psilata, thirdly Chytroeisphaeridia minor subsp. psilata, fourthly (and now) Kallosphaeridium? helbyi subsp. psilatum. Taxonomic senior synonym: Sentusidinium explanatum, according to Wood et al. (2016, p. 84–85). Age: late Albian–early Cenomanian.

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Original description as Canningia? minor var. psilata: [Burger, 1980]:

Description:
Cyst spherical to egg-shaped, without apical or antapical horns.
Archaeopyle apical with a circular outline, margin notched, outlining the presence of 6 precingular paraplates.
No other traces of paratabulation are visible.
Cyst wall single-layered, psilate, 0.5-1.5 μm thick.

Dimensions:
Apical diameter (26 dehisced specimens) 32-(50)-65 μm, width (34 specimens) 26-(46)-84 μm.

Remarks:
The specimens from the Surat Basin are consistently psilate, in which respect they vary from Canningia minor itself.