Thallus: tightly adnate to adnate, foliose, 2-6 cm in diam.; subdichotomously lobate; lobes: narrow, sublinear,, contiguous and often imbricate, elongate, plane, 0.5-2 mm wide; apices: subrotund, often lacinate, ciliate; cilia: simple, up to 0.8 mm long; upper surface: whitish to greenish gray, smooth, shiny, epruinose, emaculate, densely isidiate,; isidia: cylindrical or slightly flatted and becoming lobulate-coralloid, apically spinulose to short-ciliate; soredia and pustulae absent; medulla: white; lower surface: black with a narrow, naked brown zone peripherally, densely rhizinate, rhizines black, simple to rarely squarrose or dichotomous; Apothecia: rare, laminal, sessile, 1.5-4 mm diam.; margin: isidiate; disc: brown; ascospores: simple, broadly ellipsoid, 16-18 x 10-12 µm; Pycnidia: rare, laminal, immersed; conidia: cylindrical, 3-5 x 0.5 µm; Spot tests: cortex K+ yellow, C-, KC-, P+ yellow; medulla K-, C+ rose, KC+ red, P-; Secondary metabolites: upper cortex with atranorin and chloroatranorin; medulla with 3-methoxy-2,4-di-O-methylgyrophoric acid (major), gyrophoric, 2,4-di-O-methylgyrophoric, 5-O-methylhiascic, lecanoric and umbilicaric acids (all minor) and hiascic, 2-O-methylhiasic, 2,4,5-tri-O-methylhiascic, 4,5-di-O-methylhiascic, 3-hydroxyumbilicaric, 3-hydroxygyrophoric, 3-methoxyumbilicaric and 4-O-methylgyrophoric acids (all trace).; Substrate and ecology: frequent on bark, rocks or mosses over rock in forests; World distribution: pantemperate and montane pantropical; Sonoran distribution: mountains of SE Arizona and Sinaloa in the Sierra Madre Occidental.