Weingartia

Weingartia is a genus of small cacti native to the Andean region, mainly Bolivia and northwestern Argentina. Prized for their compact shape and spectacular flowering, these slow-growing cacti adapt very well to cultivation in pots. Morphology: They are small to medium-sized plants, usually with a globular or short columnar shape, and may have tubercles or nipples instead of well-defined ribs.
They have a dense covering of spines that vary in length and rigidity depending on the species.