Mexico, Sonora, Rancho El Pinito, Arroyo Cajon Bonito, 56.5 km (by air) ESE of Agua Prieta, Cuenca Los Ojos Foundation conservation area, Sierra San Luis.
31.190556 -108.940833
31d 11m 26s N; 108d 56m 27s W
1432 meters (4697ft)
Sycamore-Arizona cypress-oak canyon forest.
Locally uncommon 1.8 m tall herbaceous perennial; flowers white.