Cirsium arizonicum var. rothrockii
Variety rothrockii is endemic to Chiricahua, Dos Cabseos, Huachuca, Peloncillo, Pinal, Pinaleno, Sierra Ancha, and White mountains of southeastern Arizona and adjacent New Mexico, where it largely replaces var. arizonicum. The name Cirsium rothrockii has been misapplied to similarly glabrous plants of the Four Corners region (e.g., S. L. Welsh 1983), but those plants are assigned here to other varieties.