English: Ash Cactus.
Habitat: variable, top of or on stony hillslopes, plains; sandy, rocky, sometimes schistose soils; in the puna among grasses; full sun; from 250 up to 3800 m in altitude. Region: widespread; south Africa, Argentina.

BotanySmall bushy to shrubby plants; dense terminal or subterminal branches, numerous globose or cylindrical segments, appear stacked on top of each other.
Stem: ash grey colour.
Roots: tuberous.
Leaves: tiny, deciduous.
Stem: areoles with trichomes, glochids sunk in cavities; spines sometimes absent.
Flowers: diurnal, self-sterile, rotate, appearing at the apex of segments, white or pink, also yellow, orange or red.
Pollination: by specialized hymenoptera (Alloscirtetica lanosa).
Fruits: dry or juicy, dehiscent when ripe.
Seeds: large, irregular, creamy-white to brown, piled up in fruits, embryo comma-shaped, perisperm prominent.
Dispersion: by wind, in the excreta of animals, chinchillas and llama guanicoe.