Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: foliose, circular in outline or irregularly spreading, up to 15 cm wide, loosely adnate to adnate, lobate lobes: flat to convex, discrete, loosely imbricate, short linear, 2-5 mm long, mostly 0.5-2 mm wide, tips truncate, strongly crenulate upper surface: pale gray to ash colored (ochre in herbarium), dull or somewhat shiny, emaculate; pseudocyphellae punctiform to sublinear, up to 1.3 mm long and 0.12 mm wide; without soredia or isidia upper cortex: paraplectenchymatous, c. 35 micrometer thick, composed of 4-5 layers, lumina 2-4 micrometer diam., brown medulla: white, c. 200 micrometer thick, often with internal cephalodia lower cortex: c. 20-25 micrometer thick, composed of 3-4 layers, pale brown lower surface: pale brown, densely short (>10 [or 25] micrometer long) tomentose, moderately rhizinate; rhizines: simple, up to 0.1 mm long, concolorous with lower surface Apothecia: laminal, stipitate, up to 8 mm diam., margin crenulate; disc: red brown; epithecium: brown, c. 10 micrometer thick; hymenium: hyaline below, c. 120 micrometer thick, I+ blue; subhymenium colorless, c. 40 micrometer thick; hypothecium c. 20 micrometer thick; paraphyses: simple, cylindrical, septate asci: obclavate, 8-spored ascospores: acicular, 7-septate at maturity, colorless, 70-90 x 5 micrometer Pycnidia: immersed, punctiform, upper portion blackish brown conidia: not seen Spot tests: upper surface K+ yellow, C-, KC-, P-; medulla K-, C-, KC+ rose, P- Secondary metabolites: cortex with substance "A"; medulla with gyrophoric acid (major) and 4-O-methyl gyrophoric acid (minor). Habitat and ecology: on bark or rock in very humid microclimates World distribution: Mexico to northern Chile, northern New Zealand and Pacific Islands from Easter Island to Hawaii Sonoran distribution: Sierra Madre Occidental region of central Sinaloa.