Mammillaria heyderi var. bullingtoniana

This is a reasonably common cactus in rocky areas at lower elevations in southeastern Arizona and adjacent New Mexico. It is apparently easily confused with Mammillaria meiacantha, which is often considered a variety of M. heyderi and overlaps the distribution of M. heyderi var. bullingtoniana slightly near the Rio Grande.

Plant habit in the Chiricahua Mts. between Portal & Paradise, 5 Sep 2004.

Plant habit on the ridge separating Ice Canyon and Bar Canyon in the Organ Mountains, 27 Jan 2008.