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

Life habit: lichenized Thallus: foliose, circular in outline or irregularly spreading, 2-30 cm wide, loosely to tightly adnate, lobate lobes: flat to convex, discrete, often loosely imbricate, elongate, mostly <2 mm wide, tips often ascending, eciliate upper surface: pale whitish gray, greenish gray or bluish gray, dull or somewhat shiny, emaculate and lacking pseudocyphellae; with or without soredia or isidia upper cortex: paraplectenchymatous with a non-pored epicortex medulla: white, with or without a chondroid strand; hyphal walls: containing Cetraria-type lichenan photobiont: primary one a trebouxioid alga, secondary photobiont absent lower cortex: absent lower surface: brown-black, with a continuous or discontinuous, prominent, dense spongiostratum (spongy hypothallus), with or without rhizines; rhizines: simple or or sparingly branched, stout, apically with a squarrose tuft Ascomata: apothecial, lecanorine, laminal, sessile to substipitate: disc: brown to black, eperforate; epithecium: pale brown; hymenium and hypothecium colorless; paraphyses: simple or forked above, apices clavate, pale brown with a dark brown cap asci: cylindrical, many (more than 20) spored, Lecanora-type ascospores: simple, curved Conidiomata: pycnidial, brown-black, immersed, punctiform conidia: simple, bacilliform, colorless Secondary metabolites: depsides, depsidones and aliphatic acids Geography: world-wide, except Europe, most common in east Asia in temperate to subtropical regions, extending to New Guinea, and Oceania, Central and South America (Andes), eastern North America Substrate: common on bark of trees and on rocks.