= Thelocactus leucacanthus var. ehrenbergii (Pfeiff.) Bravo
Cact. Suc. Mex. 25: 65. 1980
Accepted Scientific Name: Thelocactus leucacanthus (Zucc. ex Pfeiff.) Britton & Rose
Cactaceae (Britton & Rose) 4: 8. 1923 [24 Dec 1923] Britton & Rose
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Thelocactus ehrenbergii (Thelocactus leucacanthus var. ehrenbergii) Photo by: Peiffer Clement
Origin and Habitat: Ixmiquilpan, Mexico.
Synonyms:
See all synonyms of Thelocactus leucacanthus
Description: Thelocactus leucacanthusSN|1067]]SN|1067]] var. ehrenhergii (syn: Thelocactus ehrenhergii and Echinocactus ehrenhergii) is a cespitose cactus species that forms dense cushions. It is generally included within (as a synonym of) Thelocactus leucacanthus, suggesting that there is not really a fundamental difference between the two, but T. ehrenhergii usually has pink-rose flowers while T. leucacanthus has mostly yellow flowers. The description of Britton and Rose (Cactaceae:1923) included the following information: “...We are inclined to refer here Echinocactus ehrenhergii Pfeiffer (Allg. Gartenz. 6: 275. 1838), which, according to Schumann, also came from Ixmiquilpan, Mexico. In his monograph Schumann describes the flowers as yellow like those of E. leucacanthus, but in his English Keys he says that the flowers are rose-red. Dr. Rose, who collected in this region in 1905, found only one species of this relationship...”
For more details see: Thelocactus leucacanthusSN|1067]]SN|1067]]
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Subspecies, varieties, forms and cultivars of plants belonging to the Thelocactus leucacanthus group
Thelocactus leucacanthus (Zucc. ex Pfeiff.) Britton & Rose: (subsp. leucacanthus) has pale-yellow flowers. Distribution: It grows mostly in Hidalgo.
Thelocactus leucacanthus var. ehrenbergii (Pfeiff.) Bravo: same as T. leucacanthus but flowers rose-red. Distribution: Ixmiquilpan, Mexico.
- Thelocactus leucacanthus subs. schmollii (Werderm.) Mosco & Zanov.: has large tubercles rather than distinct ribs, looks more like a Coryphantha than it does a Thelocactus. It has violet to carmine red flowers. Distribution: Mainly in Queretaro.
Bibliography: Major references and further lectures
1) Nathaniel Lord Britton, Joseph Nelson Rose “Cactaceae: Descriptions and Illustrations of Plants of the Cactus Family” volume 4, 1923
Cultivation and Propagation: Thelocactus ehrenhergii is a summer grower species easy to cultivate. Water regularly from Spring to Autumn, but do not overwater, can become too elongated if compost is too rich. Requires full sun or light shade and careful watering to keep plant compact with strong coloured spines. Needs good drainage and very porous potting mix, In Winter, keep dry.
Reproduction: From seed or by cuttings as it produces many basal plantlets.