Rebutia (Aylostera) vallegrandensis was first published by M. Cárdenas in Cactus & Succulent Journal (US), 42(1): p.p. 35-6, in 1970.

The description is given here in the original Latin, plus Cárdenas’ own English translation and additional note. You should look up the original for further details, plus a black-and-white photograph and drawing.

Rebutia vallegrandensis Cárd. sp. nov.

Globosa vel breve cylindrica, apice depressa, dense spinifer, 4-6 cm alta, 4-5 cm crassa, herba viridis. Costis plus minusve 20, parce tuberculatis. Areolis 4-5 mm remotis, circularibus, prominentibus, albido tomentosis. Aculeis 30 vel supra, innecteribus, radiantes 3-10 mm long. tenuissime setaceis. Floribus plurimus ex lateralia vel basim caule, infundibuliformibus 2.5 cm long. 2 cm latis, rubis, parce supra ovarium curvatis. Ovario globoso 3 mm diam. viride brunescente, squamis minutis, acutis, aliquid pilis brevis albis praedito, tubo 1 cm long., 2 mm crasso, diluto rubro, squamis acutis, paucis, pilis albis, brevis instructo. Phylla perigoni exteriora manifeste diversa relatio phylla interiora, magenta rubra 13 x 4 mm, lanceolata, mucronata. Phylla interiora lanceolata 14 x 5 mm, sanguinea. Stamina ex fundo tubo usque basim petalis 7-8 mm long. Filamenta alba; antherae flavae. Stylo 1.5 cm long, stamina superante, albo, 5 lobis stigmaticis flavis 2 mm long, coronato. Fructo globoso 3.5 mm diam. Semina subglobosa, truncata, 1.2 mm long, nigra, puncticulata.

Patria: Bolivia. Provincia Vallegrande. Departamento Santa Cruz, vicinis Candelaria, 2,000 m.

English translation

Globose to short cylindric, depressed at apex, densely spined, 4-6 cm high, 4-5 cm thick, fresh green. Ribs about 20, somewhat tuberculate. Areoles 4-5 mm apart, prominent roundish, whitish felted. Spines interlaced over 30, spreading, 3-10 mm long, bristle-like, very thin, acicular. Flowers numerous from the lateral sides and the base of stem, funnelform, 2.5 cm long, 2 cm limb slightly curved above ovary. Ovary globose 3 mm diam. brown greenish with very small acute scales bearing few white short hairs. Tube narrow as in Aylostera, 1 cm long, 2 mm thick, light red with few acute scales which show some short white hairs. Outer perianth segments distinct from the inner ones, magenta red, lanceolate, mucronate 13 x 4 mm. Inner segments lanceolate 14 x 5 mm bright blood red. Stamens from the bottom of the tube to the base of petals, 7-8 mm long. Filaments white; anthers yellow. Style 1.5 cm long not surpassing the stamens, white. Stigma rays 5, yellow, 2 mm long. Fruit globose 3.5 mm diam. Seeds subglobose truncate at the base or mitre shaped, 1.2 mm long, puncticulate opaque black.

Bolivia. Province of Vallegrande. Department of Santa Cruz, near Candelaria on the way to Rio Piraymiri.

March, 1969. A. M. Kruger.

Type No. 6307 in Herbarium Cardenasianum.

This curious little cactus is characterized clearly by its few hairs on the ovary and the tube, its narrow tube somewhat as in Aylostera and the differentiation of the perianth segments in two distinct whorls.
About two years ago, Walter Rausch, the known cacti collector, has given me two specimens of a plant like the above diagnosed and from the same region of this country. I do not know whether Mr. Rausch has ever described this new taxon.