This segregate of virginianum is restricted to southern Appalachian regions at about 750-1500 m in elevation (Weakley et al. 2017). Status as a species has been restored by W. There are colls. from Black Mt. in HARL: R. Athey #3106, 12Jun1975 (MUR, TENN, VDB); R. Cranfill #2606 (KY) and perhaps others (SERNEC). Also, there is probably a coll. from Black Mt. in LETC ("Whitesburg Quad."): M. Evans s.n., 12May1996 (EKY). H. atranthum differs from typical virginianum as follows (W): flowers consistently deep purple to maroon (versus white to pale purple); lower stems usually glabrous to slightly retrose pubescent (versus slightly to densely retrose or spreading); plants leafy through summer, dormant in winter (versus leafy through the winter, often becoming dormant in summer). It needs deeper investigation in Ky. and elsewhere.