Regarded by some as a form of Aylostera deminuta or A. pseudodeminuta. The main features of this plant are the areoles (as the name would suggest): bearing a lot of white (or sometimes pale brownish / off-white) wool, which makes them stand out. It is a more squat, flattened spherical plant than the aforementioned other species, and has scarlet-red flowers.
The description is here.
Plants of this species in the collection include:
Aylostera albiareolata FR761
Aylostera albiareolata RH1052