Rebutia (Aylostera) patericalyx was first described by Friedrich Ritter in Kakteen und andere Sukkulenten 28(4): p. 78, the journal of the Deutsche Kakteen-Gesellschaft, in 1977. The description is very brief, but is expanded on in Ritter’s self-published book “Kakteen in Sudamerika” volume 2, p. 611, in 1980, in German, with two black-and-white photographs on p. 786.

The original description is given here, in Latin as published, together with my own English translation, and a few notes extracted and translated from the description in Ritter’s book.

Rebutia patericalyx Ritter spec. nov.

Solitaria vel paulum prolifera, 13—30 mm crassa, viridis, radice vix rapacea; costae 13—16, dissolutae tuberculis 1,5-2,5 mm altis; areolae 1-2 mm longae, lana alba instructae, 2,5-5 mm inter se remotae; spinae pilosae, pallide flavae vel albae, marginales 12-15, lateraliter directae, 3-6 mm longae; interdum 1 centralis.

Flores 35 mm longi; ovarium lana alba et 6 ad 12 saetis pro areola instructum; stylus ca. 5 mm cum tubo coalitus; sulcus nectarifer 1 mm longus; tubus floralis pateriformis, 5 mm longus, superne 7 mm amplus; filamenta fere alba, sine lacuna insertiorum; antherae aureae; stylus flaveolus, 5 stigmata pallide flava; petala 18-20 mm longa, 6-8 mm lata, spathulata, coccinea; semina 1,2 mm longa, paulum tuberculata; habitat Cueva, Prov. Sud-Cinti, Bolivia.

Sammelnummer FR 757.

English translation

Solitary or proliferating a little, 13 – 30mm thick, green, tap-rooted; 13 – 16 ribs, split into tubercles 1.5 – 2.5mm high; areoles 1 – 2mm long, with white wool, 2.5 – 5mm apart; spines hairlike, pale yellow to white, 12 – 15 marginal spines, 3 – 6mm long, pointing sideways; sometimes a single central spine.

Flowers 35mm long and slightly wider than that; ovary with white wool and 6 to 12 whitish hairs per areole; style fused to the tube for 5mm; nectary groove 1mm long; upper flower tube bowl-shaped, 5mm long, 7mm wide at the top; filaments almost white, inserted evenly, anthers golden yellow; style yellow, with 5 pale yellow stigmas; petals 18 – 20mm long, 6 – 8mm wide, spathulate, scarlet; seeds 1.2mm long, slightly tuberculate; habitat Cueva, Province of Sud-Cinti, Bolivia.

Collection number FR 757.

Further notes

Body dark green, often burned reddish brown, with a depressed apex.

Marginal spines directed laterally, but not lying flat, glossy, pale yellow, later white, straight to bent, slightly thickened and brown at the base, 3-6mm long; sometimes a protruding brownish needle-fine central spine of a few mm.

Ovary almost spherical, 4mm dia., with narrow, 1-2mm long scales.

Flower tube pale, outside like ovary, but only a few hairy bristles below.

Style pale yellow, with 5 somewhat splayed, 2.5mm long light yellow stigmas at the level of the upper anthers.

Inner petals rounded at tip, outer petals briefly acuminate [pointed], inner intense scarlet, outer intense ruby ​​red.

Fruit spherical, 3-6mm diameter, reddish, with red flesh, covered like ovary. Seeds brown-black, 1.2mm long, 1.1mm wide.