Origin and Habitat: Mexico, Ariocarpus koschoubeyanus is widely distributed as a large number of small, isolated populations in a big area extending over 600 km, from central Coahuila in the north to Queretaro in the south, and the species is also found in the states of Zacatecas, San Luis Potosi, Nuevo Leon and Tamaulipas. The "elephantidens" is the southern form of the species.

• Ariocarpus kotschoubeyanus var. elephantidens f. cristata hort.

• Ariocarpus kotschoubeyanus (Lem. ex K.Schum.) K.Schum.
• Anhalonium fissipedum Hort.Monv. ex Lem.
• Anhalonium kotchubeyi Lem.
• Anhalonium kotschoubeyanum Lem. ex K.Schum.
• Ariocarpus rotchubeyanus Cobbold
• Cactus Kotschubeyi Kuntze
• Roseocactus kotschoubeyanus (Lem. ex K.Schum.) A.Berger
• Ariocarpus kotschoubeyanus subs. albiflorus (Backeb.) Glass
• Ariocarpus kotschoubeyanus subs. tulensis Halda
• Roseocactus kotschoubeyanus var. albiflorus Backeb.
• Ariocarpus kotschoubeyanus f. cristatus hort.
• Roseocactus kotschoubeyanus f. cristata hort.
• Ariocarpus kotschoubeyanus var. elephantidens Skarupke
• Ariocarpus kotschoubeyanus subs. elephantidens Halda
• Ariocarpus kotschoubeyanus var. elephantidens f. cristata hort.
• Ariocarpus kotschoubeyanus var. macdowellii (Backeb.) Krainz
• Ariocarpus kotschoubeyanus subs. macdowellii (Backeb.) Halda
• Roseocactus kotschoubeyanus subs. macdowellii Backeb.
• Roseocactus kotschoubeyanus var. macdowellii (Backeb.) Backeb.
• Ariocarpus kotschoubeyanus f. monstruosus hort.
• Ariocarpus kotschoubeyanus f. mostruosus proliferus hort.
• Ariocarpus kotschoubeyanus subs. neotulensis Halda
• Ariocarpus kotschoubeyanus f. rubra hort.
• Ariocarpus kotschoubeyanus subs. skarupkeanus Halda & Horáček
• Ariocarpus kotschoubeyanus subs. sladkovskyi Halda & Horáček
• Ariocarpus sulcatus K.Schum.
• Anhalonium sulcatum Salm-Dyck

Description: Ariocarpus kotschoubeyanusSN|2127]]SN|2127]] var. elephantendens is the southerly form of the species characterized by much larger, highly textured, triangulate tubercles, and a deep purple flower with little or no white content. Although they can form clumps, often only a small disc of tubercles can be seen flat at the soil surface, however these plants grow a large tap root below the surface of the compost.
Crested form: Crested kotschoubeyanus Star Rocks (Ariocarpus kotschoubeyanusSN|2127]]SN|2127]] var. elephantidens f. cristata) are very rare, slow-growing and highly priced cacti forming odd sculptural shapes. Their stems fan out and can get form a spectacular specimen. The crested form - despite to its beauty - is still very rare, pricey and sought after by collectors.
Stem: Fan shaped barely riding above ground level, flattened, depressed along the line crest on top, slowly forming brain-shaped cushion up to 2-3 cm high and 20 cm in diameter, or more.
Tubercles: The tubercles are deltoid dark olive green and highly textured, with no spines and lie flat on the soil surface. They are more long than wide, closely packed and divergent, sharply angled apically.
Areoles: The tubecles forms a central longitudinal areolar groove extending to the tips on the adaxial surfaces of the tubercles, woolly, 1-3 mm wide, 5-10 mm long.
Root: Each plant has a large turnip-like taproot, which lies below the soil surface and serves for water storage.

Bibliography: Major references and further lectures
1) James Cullen, Sabina G. Knees, H. Suzanne Cubey “The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass” Cambridge University Press, 11/Aug./2011
2) David Hunt, Nigel Taylor “The New Cactus Lexicon” DH Books, 2006
3) Edward F. Anderson “The Cactus Family” Timber Press, 2001
4) Nathaniel Lord Britton, Joseph Nelson Rose “Cactaceae: Descriptions and Illustrations of Plants of the Cactus Family” Volume 3, 1922

Cultivation and Propagation: It is not too difficult in a greenhouse, although grows very slowly. It is usually seen as a grafted plant but can grow on its own roots too.
Soil: Use a mineral well permeable soil with little organic matter (peat, humus).
Exposure: They need a good amount of light shade to full sun this help to keep the plants healthy, although slow growth.
Watering: Water sparingly from March till October (weekly during summertime, if the weather is sunny enough), with a little fertilizer added. Less or no water during cold winter months, or when night temperatures remain below 10° to prevent root loss. It is sensitive to overwatering (rot prone).
Fertilization: Feeding may not be necessary at all if the compost is fresh then, feed in summer only if the plant hasn't been repotted recently. Do not feed the plants from September onwards as this can cause lush growth which can be fatal during the darker cold months.
Hardiness: Keep perfectly dry in winter at temperatures from 5 to 15 degrees centigrade. (but it is relatively cold resistant and hardy to -5° C, or possibly colder for short periods) In the rest period no high atmospheric humidity!! (Temperature Zone: USDA 9-11)
Crested growth: Unlike 'monstrose' varieties of plants, where the variation from normal growth is due to genetic mutation, crested growth can occur on normal plants. Sometimes it's due to variances in light intensity, or damage, but generally the causes are unknown. A crested plant may have some areas growing normally, and a cresting plant that looks like a brain, may revert to normal growth for no apparent reason. If you have any of the crested part left you need to remove the normal growth and leave the crested part behind this will need to be done regularly.
Propagation: Grafting or cuttings. Plants are usually grafted onto column-shaped cacti but proved to be able to produce their own roots if degrafted. Cuttings will take root in a minimum temperature of 20° C (but better in hot weather). Cuttings of healthy shoots can be taken in the spring and summer. Cut the stem with a sharp, sterile knife, leave the cutting in a warm, dry place for a week or weeks (depending on how thick the cutting is) until a callus forms over the wound. Once the callus forms, the cutting may be inserted in a container filled with firmed cactus potting mix topped with a surface layer of coarse grit. They should be placed in the coarse grit only; this prevents the cut end from becoming too wet and allows the roots to penetrate the rich compost underneath. The cuttings should root in 2 to 6 weeks. Large crested piece must be placed on the soil surface without burying the plant base down in the soil.