The original description of Rebutia (Aylostera) brunneoradicata was published in Kakteen und andere Sukkulenten 28(4): 77-78, 1977, the journal of the Deutsche Kakteen-Gesellschaft, by Friedrich Ritter. Further details were given in Ritter’s book Kakteen in Kakteen in Südamerika vol. 2 (1980).

Here is the text of the description of this species in the original Latin, but you should look up the original description for more details. The English translation below is my own.

Rebutia brunneoradicata Ritter spec. nov.

Paulum proliferans, 10-20 mm crassa, radice rapacea longa brunnea; costae 9-12, dissoiutae tuberculis 2-3 mm altis; areolae 1-1,5 mm longae, 1,5-3 mm inter seremotae; spina 8-12, pullae vel brunneae, solum marginales, 2-3 mm longae, lateraliter directae.

Flores 26-30 mm longi ; ovarium squamis perangustis, lana alba et interdum saeta alba instructum; stylus 1-2 mm cum tubo coalitus; sulcus nectarifer 1-2 mm longus; tubus floralis 7-8 mm longus, interne pallide purpureus; filamenta pallide purpurea; insertiones plerumque inferne, superne lacuna; stylus viridis, stigmata 5-6 viridiflava ; petala 15-18 mm longa, 5-7 mm lata, spathulata, carminea, interdum coccinea, exteriora aliquid purpurea; semina ut Rebutia pauciareolata; habitat San Antonio, Prov. Mendez, Bolivia.

Collected as FR 1109

English translation

Body somewhat proliferating, 10-20 mm thick, a long brown tap root; 9-12 ribs, broken up by tubercles 2-3 mm high; areoles 1-1,5 mm long, 1,5-3 mm apart; 8-12 spines, fawn or dark brown, marginal only, 2.3 mm long, spreading sideways.

Flowers 26-30 mm long; ovary with narrow scales, white wool, and at times completely covered with white hair; style connected to the tube for 1 – 2 mm; nectary channel 1 – 2 mm long; flower tube 7 – 8 mm long, internally pale purple; filaments pale purple; mostly inserted low down but above the cavity; style green, the 5-6 stigmatic lobes greenish-yellow; petals 15-18 mm long, 5 – 7 mm wide, spatulate, carmine, sometimes red, purple edged; seed similar to Rebutia pauciareolata; habitat San Antonio, Prov. Mendez, Bolivia.

Collected as FR 1109