Living Rocks of Mexico
Ariocarpus retusus subsp. retusus
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Ariocarpus retusus is an extremely variable species, the most interesting variant being the Aramberri form, The diversity of the species is illustrated here also by the A-F forms offered by Mesa Garden, plants of which are now widely distributed in cultivation.

Original Publication

Ariocarpus retusus Scheidweiler, (1838) Bull. Acad. Sci. Brux. 5: 492


Plant grey, or blue-green, rising slightly above ground level, globose, rounded on top, 3-12cm high, 10-25cm in diam.; tubercles divergent, erect, crowded and basally compressed, usually becoming attenuate at the apices, convex or nearly flattened adaxially and often with shallow adaxial undulations or wrinkling, not fissured, 1.5-4cm long, 1-3.5cm broad, nearly as broad as long; spine-bearing portions of the areoles at the tips of the tubercles, rounded, 1-5mm in diam.; flowers 4-5cm in diam., 2-4 2cm long; outer perianth parts white, occasionally with reddish midribs, 1.2-2cm long, 5-8mm broad; inner perianth parts white or rarely magenta, 1.4-2cm long, 5-9mm broad; pistil not exerted above the stamens; style 1.4-2.1cm long; stigmas 7-16, 2.5-9mm long; fruit white, green, or rarely pinkish, 1025mm long, 3-10mm in diam.

Ariocarpus retusus

A typical plant of the species flowering in October



Distribution (Map)

Ariocarpus retusus, is along with Ariocarpus kotschoubeyaanus, one of the most widely distributed species in the genus, It ranges from north of Saltillo, Coahuila southwards to San Luis Potosi, SLP, the easterly limits of the species occur in Tamaulipas, populations are also found in Zacatecas and Nuevo Leon. A retusus  ssp. retusus is a plant of the high Chihuahuan desert occurring at altitudes of between 1300 and 2000 metres, on calcareous hillsides and occasionally gypsum plains. At lower altitudes (200 - 800m) of the Sierra Madre Oriental it is replaced by A. retusus ssp. trigonus.


This species, the type of the genus is, as might be expected with such a wide distribution range is highly polymorphic. Tubercle size and shape vary widely, a terminal areole may or may not be present, flower color ranges from white to pink, or even bicolored (see The Aramberri Enigma). The range of variation has been further increased by the reduction of A. trigonus to sub-specific rank under A. retusus by Anderson.  The vast amount of phenotypic variation in the species has led to the erection of several variants,  A. furfuraceus, has been applied to plants with equilaterally triangular  shaped tubercles, A furfuraceus var. rostratus refers to plants with a more tapered apex to the tubercle. 

  Ariocarpus furfuraceus

Ariocarpus retusus 'furfuraceus', with equilaterally triangular tubercles

Ariocarpus retusus scapharostoides

A. retusus 'scapharostroides', a recently described variant


The most recently described variants are A. confusus, discussed here separately (The Aramberri Enigma), and A. retusus var. scapharostroides both  published by Halda & Horacek in 1998. A. retusus var. scapharostroides is based on plants from the Villa Juarez region of SLP, it is characterized by erect angular tubercles, superficially reminiscent of A. scaphirostris, this variety awaits further evaluation but would appear to represent just another variant of the A. retusus complex. Seed of this plant is available under the field number PP232, the plant offered by Mesa Garden as A. retusus form A also equates to A. retusus var. scapharostroides. Other recently published names associated with this species are A. retusus subsp. jarmilae, A. retusus subsp. horaceki, and A. retusus subsp. panarottoi. A retusus var mnimus is a nomina nuda which has recently been applied to plants from Echido Nuncio,in  San Luis Potosi.

Ariocarpus retusus is of easy culture in a well drained calcareous clay compost, with ample water during the growing season. It is probably the easiest species of the genus to raise from seed, but will generally take about 10 years to reach flowering size under United Kingdom conditions.

Field Numbers

A full listing of all associated field data can be found on the field number reference pages.

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