This species occurs only in the Knobs region of Ky., where it appears to have diverged from clinopodia into drier woods. Similar plants in Scioto County of se. Ohio appear closer to clinopodia (collected by L. Braun for US and J. Campbell). These Ky. plants are restricted to thin subxeric woods on somewhat calcareous soils, usually in transitions from clifftops and ledges (with Juniperus, Fraxinus quadrangulata, Quercus muhlenbergii) to narrow sandy ridges above, or to siltstone slopes below (with Q. alba, Q. rubra, F. americana, Carya ovata, C. glabra). It often occurs with Carex spp. (especially pennsylvanica), in contrast to adjacent ground with more exposed limestone, dominated by Diarrhena americana and Polymnia canadensis. The names M. russeliana Nutt. or M. virgata Raf. have been applied to this species by previous authors (including F and Cr). But those names apply only to plants of Ozarkian regions that are distinguished by their relatively long upper corolla lips (ca. 10-16 mm versus 7-10 mm in the clinopodia group), more strongly inward-arched lower lips, calyx tubes usually with long multicellular hairs (versus none) but teeth relatively short (1-2 mm versus 2-4 mm); leaves tapering from relatively broad, abruptly truncate bases (resembling bradburiana but usually narrower and more petiolate), wth petioles only ca. 1-5 mm (versus 3-7 mm). A few colls. resembling this new species appear to be introgressed with clinopodia or fistulosa (or perhaps media), including some from MADI (GH, KY) and POWE (Medley #473 at APSC). However, its closest relative may be M. brevis (Fosberg & Artz) Floden, known only from the Ridge-and-Valley of W.Va. and Va. (W). M. brevis differs most clearly in its leaves, which are mostly 1-3 × 0.5-1.5 cm (versus 3-8 × 1-2.5 cm), the margins with appressed hairs, 0.1-0.2 mm long (versus spreading hairs ca. 1-1.5 mm long ), the upper surface not distinctly dark or glossy (versus relatively dark green and lustrous hen fresh).