This is centered in the Great Plains and extends locally into eastern states. In Ky. it is largely restricted to remnants of dry calcareous grassland in or near the Big Barrens, and along the western Knobs (including a 1940 coll. of P.A. Davies at GH from along Poplar Level Road in JEFF). There are also records from the western escarpment of the Cumberland Plateau in Tenn. (Ch, K), but none from eastern Ky., where it might be expected.