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, 4-10 cm in diam., lobate lobes: sublinear, contiguous, elongate, plane to subconvex, separate, 2-5 mm wide, apices truncate upper surface: whitish gray, smooth to slightly ridged, matt, frequently densely pruinose, becoming cracked along prominent, effigurate pseudocyphellae isidia: granular to subsorediose, laminal, dense; soredia and pustulae absent medulla: white with continuous algal layer lower surface: black, rhizinate; rhizines: moderately dense, black, simple to sparsely furcate Apothecia: rare, laminal, substipitate, 2-4 mm wide; margin: usually isidiate; disc: red brown to dark brown asci: clavate, 8-spored ascospores: broadly ellipsoid, 14-16 x 9-12 µm Pycnidia: not seen 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 chloroatranorin; medulla with salazinic acid (major) and consalazinic acids (minor). Substrate and ecology: on trees World distribution: Pacific NW in North America down to southern California Sonoran distribution: only known from a few locations in southern California.