This is known only from the Cumberland Plateau, mostly in Tenn., and from smaller disjunct populations in the Blue Ridge of N.C. and in the Ridge & Valley of Va. (FNA 3, W). H. contracta is closely related to the larger-flowered H. shuttleworthii (Britten & Baker f.) Small, a more widespread southern Appalachian species that occurs nearby on the Plateau in Tenn. and in the Ridge & Valley of Va. H. contracta has also been confused with heterophylla, which has been misidentified as contracta in LETC (e.g. in earlier Natural Heritage databases). Some plants along Rock Creek in w. MCRE can appear hybridized with ruthii, but probably just represent variation within contracta; hybrids are not reported in the genus (FNA 3; W). Together, contracta plus shuttleworthii differ from heterophylla plus virginica as follows (W): calyx tube broadly urceolate-campanulate or rhombic-ovate, broadest near the middle (versus cylindrical to narrowly cylindro-urceolate, not clearly wider near middle).