All five varieties occur in northern Mexico (Chihuahua, Coahuila, Durango, Nuevo León, Sonora, and Zacatecas) in oak and conifer woodlands, commonly above 2200 m elevation. In addition to var.
atrorubens (including var.
psuedociliatum Reveal), they are var.
auritulum W. J. Hess & Reveal, var.
intonsum Reveal, var.
nemorosum W. J. Hess & Reveal, and var.
rupestre (S. Stokes) W. J. Hess & Reveal.