THELOCACTUS HEAEDROPHORUS

THELOCACTUS HEXAEDROPHORUS Is a solitary and quite variable cactus with flattened stems. Many local forms are known, often formally described, that differ in stem, spine or flower morphology. Because of the large variability of the species in the whole distribution area, none of these are recognised today.Stems are globose or somewhat flattened above or umbilicate, glaucous, olive-green, or greyish-green eventually tinged in pink or purple, 3-7,5 cm tall , 8-15(-20) in diameter (eventually grows a little taller in cultivation), strongly tubercled and not ribbed.Ribs are 8-13 indistinct, but generally evident in adult plants.Tubercles are fat, prominent, polygonal-rounded (hexagonal or pentagonal based), arranged in indefinite spirals, not flattened laterally, sometime compressed at the tip, 8-20 mm long, 13-27 mm large.Areoles are 4-13 mm long, 12-28 mm apart, on top of the tubercles, elongated into a short groove, without nectar secreting glands. Spines are usually strong and variable in length depending on the clone often difficult to distinguish as centrals and radials.Flowers are silvery-white or rarely pinkish with more or less magenta midribs, 4,5-5,5(-10) in diameter, broader than long when expanded .