This globally rare species occurs mostly in the central Appalachians, but has disjunct records as far west as Mo. (FNA 3, K). It has been reported from Ky., but records are obscure or incomplete (M, J). There is a coll. of C.W. Short (GH) that might be from Ky. D. exaltatum is known from southern Ohio, and it may be expected in thinly wooded ravines of LEWI, draining from the more open calcareous uplands. It is also known from the Ridge and Valley of Tenn. (Ch+).