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, 2-8 cm in diam., lobate lobes: subirregular, elongate, slightly imbricate, plane, separate, 5-8 mm wide; apices: rotund, eciliate upper surface: gray with some blackened areas, smooth, shiny, sometimes white pruinose, conspicuously white maculate 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 Apothecia: not seen Pycnidia: not seen Spot tests: upper cortex atranorin K+ yellow, C-, KC-, P-; medulla K-, C-, KC-, P- Secondary metabolites: upper cortex with atranorin and chloroatranorin; medulla with caperatic acid (major), protolichesterinic acid (minor). Substrate and ecology: on rocks in open habitats World distribution: neotropics and SW USA Sonoran distribution: lower montane of SE Arizona southwards through the thorn forests of Sonora and Sinaloa.