Aylostera deminuta, synonym Rebutia deminuta, is a species of flowering plant in the family Cactaceae, native to Bolivia and northwest Argentina.

[1] The exact delimitation of the species varies, but sources agree that it is a short cactus with ribbed stems and orange to red flowers.

Like other members of the clade to which it belongs, Aylostera deminuta usually has fibrous rather than tuberous roots.

[1] Aylostera was generally sunk into Rebutia until phylogenetic studies from 2011 onwards led to Rebutia being split up, and the placement of the species in Aylostera was restored.

[7][2] A 2016 molecular phylogenetic study of the genus proposed a very broad circumscription of the species, reducing many species that are accepted by Plants of the World Online as of December 2024[update] to synonyms of Aylostera deminuta, including:[2] A. deminuta is native to Bolivia and north-western Argentina.