Geophytic cactus of a perfectly spherical shape, depressed at the apex, where a typical white down pops up. The color of the body may vary: quite often it is dark purple, but sometimes it may be even greyish-green or black. Its ribs are similar to tubercles, on which white areoles can be seen. Light and rather short combed spines grow out of those areoles, and are quite attached to the body of the plant. Its inflorescences have a funnel shape (common characteristic of this family), with colors, that can vary from pink to yellow.