United States, Arkansas, Washington, University of Arkansas, Fayetteville.
Perennial herb common in shady canyon among rocks. Raised from achenes from Van Devender & Van Devender 84-36 (see collection note), in the greenhouse at Fayetteville. Plant near C. sonoranus Sherff, but aches aristate and plant very pubescent - - probably a new species. Chromosome number: n = 12. Pollen stainability = 94%. 3 January 1984 (greenhouse-grown material)