Mammillaria boolli

Native to Sonora, Mexico. Mammillaria boolli is a clumping plant with soft, green or gray-green epidermis.

Stems: Up to 5 cm wide (but often more large in cultivation), with prominent rounded tubercles usually depressed globose to depressed conical when growing in habitat. While cultivated plant have (frequently) oblong offsetting stems.

Will produce large pink flowers located at the top of the plant. The fruit is red, thin-skinned.

Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz