Mammillaria
（重定向自Nipple cactus）
The genus Mammillaria is one of the largest in the cactus family (Cactaceae), with currently 200 known species and varieties recognized. Most of the mammillarias are native to Mexico, but some come from the southwest USA, the Caribbean, Colombia, Venezuela, Guatemala and Honduras. The common name "pincushion cactus" refers to this and the closely related genus Escobaria.