Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.

Thallus: foliose, adnate to loosely adnate, 2-20 cm in diam., lobate lobes: subirregular, elongate, slightly imbricate, plane, separate, 4-8 mm wide; apices: rotund, ciliate; cilia: up to 2.0 mm long upper surface: gray, smooth, dull, emaculate soredia: granular, common, in linear to orbicular, laminal or marginal soralia; 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: rare, substipitate, up to 30 mm in diam.; margin: crenulate; disc: brown, imperforate ascospores: ellipsoid, 12-17 x 6-9 µm Pycnidia: common, punctiform conidia: sublageniform, 4-6 x 1 µm 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: usually on trees in open habitats, rarely on rocks World distribution: pantropical and pantemperate Sonoran distribution: SE Arizona, southern California, Sierra Madre Occidental region of Chihuahua, Sonora and Sinaloa Baja Califoria and southern mountains of Baja California Sur.