Mammillaria

About

Mammillaria is one of the largest genera in the cactus family (Cactaceae), with currently about 170 to 190 accepted species and around 99 subspecies. Most of the mammillarias are native to Mexico, while some come from the Southwestern United States, the Caribbean, Colombia, Guatemala, Honduras and Venezuela. The common name "pincushion cactus" refers to this genus and the closely related Escobaria.

Summary from Wikipedia