Thallus forming regular or irregular, complete or partial rosettes or irregularly encircling twigs and then often fragmentary, loosely to closely attached, 3-5(-8) cm diam. Lobes few to numerous, 1-2 mm wide, often discrete at margins or intricately interwoven, zig-zag, often markedly contorted centrally, terminal lobes subdichotomously branched, margins notably sinuous-angular, not, or sparingly blackened, upper and lower surface of internal cavity white. Upper surface convex, occasionally where lobes are bunched forming ridges, glaucous or greyish, smooth, slightly glossy. Perforations numerous, rather regularly distributed, margins elevated and becoming sorediate, to 0.5 mm diam., in median line. Soralia mainly confined to and surrounding perforations, white, finely granular, rarely a few laminal and not associated with perforations. Apothecia rare, 2-8 mm diam., ± pedicellate often with ± crenulate and ± sorediate margins, disc brown, shining, subconcave to plane, epruinose, exciple slightly wrinkled, concolorous with thallus. Epithecium not granular. Asci 2-spored. Ascospores simple, oval to ovoid, 45-56 × 20-32 µm, wall 4-5 µm thick. Chemistry: Stictic, constictic, norstictic (tr.) and menegazziaic acids, atranorin (cortex ±), and accessory compounds, medulla K+ yellow → orange, C-, KC+ orange, Pd+ orange.