Aylostera (Rebutia) pseudodeminuta was first described by Curt Backeberg in Der Kakteenfreund, Vol 2(1), p. 7, in 1933. I have been unable to locate the original publication but the description was repeated in “Blatter Kakteenforsch”, the Bulletin of Cactus Research, published by Volksdorf, Germany, in 1934, of which Backeberg was the editor. The description was published with a black-and-white photograph and is given here in Latin as published, together with Backeberg’s own English translation.
REBUTIA PSEUDODEMINUTA Bckbg. n. sp.
(Der Kakteenfreund, 2. Jahrgang, Heft Nr. 1, 1933)
Proliferans; costae in mammillas parvas disolutae. Ac. radiales ca. 11. minimi, vitrosi; centrales 2-3, longiores, tenues, pungentes, clari, brunneo-cuspidati.
Flos ca. 3 cm latus, aureo-tinctus (ut cheiranthus coloratus). Stylus staminiaque cum tubo connexa. Fructus parvus, albis setis obtectus.
Patria: Salta (Argentinia sept.), ad 3000 m alta.
Forming groups, fresh green, small areoles on neat tubercles. One tiny erect radial spine, 10 others spreading, 3-7 mm long, all white, glassy. 2-3 thin, sharp, glassy central spines, the uppermost up to 13 mm long. All the spines ± brown tipped. Flowers golden, powdered with gold dust, ca. 3 cm diameter. Pistil and stamens whitish, united to the tube. Fruit small, covered with bristles. Seeds dull.
Occurrence: Salta (N. Argentina) at ca. 2500 m.