Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: foliose, monophyllous, often deeply indented or incised and appearing polyphyllous, 2-6(-8) cm in diam., rather loosely attached by a central, irregular umbilicus, easily broken lobes: broadly rounded to somewhat ragged-lacerate, folded to imbricate centrally, (0.5-)1-4(-6) cm wide; margins: broadly rounded, occasionally shallowly indented or incised, thinly ridged below and often rolled under upper surface: livid slate gray, dark glaucous gray to blue-black, suffused red-brown in parts when moist, pale glaucous-gray to brown when dry, shallowly to deeply wrinkled or subfaveolate, dull to somewhat scabrid-areolate, rather papery and thin when well developed, flabby when moist, brittle when dry, with minute, white maculae delicately marbling upper surface (x 10 lens, moist), rarely phyllidiate, soredia absent but commonly densely isidiate isidia: minute, granular, styliform, brown-black, glossy, very delicate and friable, in clusters at margins and on thalline ridges, often coalescing into a dark, sooty, diffractive crust, rarely developing into small, flattened phyllidia or into small, secondarily attached lobes or forming distinctly stalked lobate structures medulla: white, K- photobiont: cyanobacterial lower surface: pale cream white to buff at margins, pale brown centrally, wrinkled-ridged to sub-faveolate, densely tomentose from margins to center, with velvety to woolly, white to pale gray, glistening tomentum cyphellae: common, flat, crateriform, (0.1-)0.5-2(-3) mm in diam., with sharply defined, narrow margins slightly projecting above tomentum, with a white basal membrane Apothecia: rare, when present scattered, marginal and laminal, sessile, constricted at base, insertion of disc forming a prominent cavity on lower surface, rounded, 0.52(-3) mm in diam. disc: pale to dark red-brown, plane to subconvex, epruinose margins: concolorous initially but then paler than the disc, entire to crenulate to occluded, occasionally with minute, projecting, glistening white hairs below; epihymenium: pale red-brown to yellow-brown, 12-20 µm thick hymenium: hyaline to pale straw-yellow, 110-125 µm tall: hypothecium: pale yellow-brown, opaque, 30-45 µm thick asci: clavate, 57-80 x 12.5-17.5 µm, 8-spored ascospores: hyaline, 1-3-septate, fusiform-ellipsoid, with pointed apices, 22-33(-38) x 5-7 µm Pycnidia: rather rare, scattered towards lobe margins, immersed; ostiole: red-brown to black, punctate, depressed, 0.01 mm in diam. conidia: bacilliform, straight, hyaline, 4-6 x 1 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on bark (Abies, Quercus) and mossy, acidic rocks in pine-oak-fir forest, on shady faces and in areas of high humidity and moderate to deep shade, 340-3600 m World distribution: cosmopolitan and widespread in temperate regions of the Northern and Southern Hemispheres Sonoran distribution: Arizona, southern California, and Chihuahua.