Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: foliose, loosely adnate, 3-25 cm in diam., lobate lobes: subirregular, elongate, becoming somewhat imbricate, plane, separate, 8-20 mm wide; apices: rotund, eciliate upper surface: gray, smooth to rugulose, dull, emaculate, becoming reticulately cracked with age; soredia, isidia and pustulae: absent medulla: white with continuous algal layer lower surface: black with brown naked zone peripherally, centrally rhizinate; rhizines: scattered, simple, black Apothecia: common, substipitate, up to 10 mm in diam.; margin: crenulate, emaculate; disc: brown, perforate ascospores: ellipsoid, 28-32 x 14-16 µm Pycnidia: not seen Spot tests: upper cortex K+ yellow, C-, KC-, P-; medulla K+ yellow turning deep red, C-, KC-, P+ orange Secondary metabolites: upper cortex with atranorin and chloroatranorin; medulla with salazinic acid (major) and consalazinic acids (minor). Substrate and ecology: montane usually on trees in open habitats World distribution: neotropics and India Sonoran distribution: Sonora, in the Sierra Madre Occidental.