Mammillaria humboldtii

Native to the Mexican states of Hidalgo and Queretaro, this small succulent cactus inhabits semi-arid landscapes. Its rounded, somewhat flattened stems grow singly or produce clusters from the base. Numerous fine white radial spines cover the tubercles, while central spines are absent. White wool and bristles fill the spaces between tubercles. The flowers have reddish inner segments with pale pink margins and orange anthers. It is Critically Endangered in the wild. Photographed in Florida.