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, 3-10 cm in diam., irregularly lobate lobes: subirregular, elongate, plane to subconvex, separate, 3-6 mm wide; apices: rotund, eciliate upper surface: pale gray to greenish gray, strongly reticulately ridged, rugulose, shallowly foveate, becoming cracked with age, dull, sometimes white pruinose and maculate soredia: farinose, common, initially in laminal orbicular soralia but becoming confluent; isidia and pustulae absent medulla: white with continuous algal layer lower surface: black centrally, brown zone peripherally; rhizines: sparse, black, sometimes pale tipped, simple Apothecia: not seen Pycnidia: rare, immersed conidia: filiform 12-15 x 1 micro meter Spot tests: upper cortex K+ yellow, C-, KC-, P+ yellow; medulla K + orange, C-, KC-, P+ orange-red Secondary metabolites: upper cortex with atranorin and chloroatranorin; medulla with stictic acid (major), constictic acid (minor), and cryptostictic acid (minor to trace). Substrate and ecology: on hardwood trees and rocks in moist, montane canyons at mid-elevations World distribution: SW Europe, southern U.S.A., Mexico, South America, Africa, India, Australia Sonoran distribution: SE and E Arizona southwards through the Sierra Madre Occidental in Chihuahua and Durango.