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

Thallus: adnate, foliose, 4-20 cm in diam., lobate lobes: sublinear, contiguous to imbricate, elongate, plane, separate, 2-4 mm wide, apices truncate upper surface: gray, smooth to strongly foveolate, shiny, sometimes white pruinose, becoming cracked along prominent, effigurate pseudocyphellae soredia: granular, abundant, laminal, in linear soralia; isidia, pustulae and dactyls absent medulla: white with continuous algal layer lower surface: black, rhizinate; rhizines moderately dense, black, simple Apothecia: rare, laminal, 2-8 mm wide; margin: usually sorediate; disc: dark brown asci: clavate, 8-spored ascospores: ellipsoid, 11-14 x 6-8 µm Pycnidia: infrequent, immersed conidia: bacilliform, 6-8 x 1 µm Spot tests: upper cortex K+ yellow, C-, KC-, P+ yellow; medulla K+ yellow turning deep red, C-, KC-, P+ orange Secondary metabolites: upper cortex with atranorin and chlorotranorin; medulla with salazinic acid (major) and consalazinic acids (minor). Substrate and ecology: common on trees in open habitats, occasionally on rocks World distribution: pantemperate and southern boreal Sonoran distribution: relatively common on deciduous and coniferous trees in montane habitats of Arizona, on coastal oaks in California and on rocks in the high mountains of northern Baja California.