Its habitat stretches across several states in northeastern Mexico: Coahuila, Nuevo León, San Luis Potosí, and Tamaulipas.
Unlike some puffball-like mammillaria, Mammillaria candida has spines which really mean business. I thought it looked soft and friendly so I started to repot it without gloves. I thought if I moved slowly and gently I could just turn it upside down with one hand and rest it ever-so-lightly in my other hand. Big mistake! After trying this maneuver gingerly a couple times, I gave up. I can try again in the spring. With gloves.
M candida is sometimes separated from the rest of Mammillaria into its own genus, Mammilloydia, because its seeds are not pitted and lack the perisperm found in all other mammillaria. Recent molecular studies, however, place M. candida squarely within Mammillaria, a huge genus which includes many cacti much more distantly related than Mammillaria candida.
- Mammillaria candida - Photo : Willy at Mammillarias.net