Primary thallus: squamulose, persistent; squamules: 3-10 mm long, 2-5 mm wide, sparsely divided into roundish lobes, glaucescent green above, white or towards the base orange below; margins: esorediate podetia: 7-35 mm tall, stalk 1-2 mm thick, greenish, yellowish or whitish gray, cup-bearing; cups: 4-7 (-15) mm wide, generally symmetrical base, usually single, occasionally prolixferating from the margins (or rarely centers) to form another cup surface: areolate-corticate at the base; fertile podetia: with a fairly continuous cortex that may extend to the cup margins; sterile podetia: with the upper part of podetium densely covered by bullate granules (also inside the cups) and irregular scaly plates (elevated areolae), often in part squamulose, esorediate; surface structures: disintegrating and exposing the medulla Apothecia: infrequent, red, up to 4 mm wide ascospores: fusiform to oblong, 6-12 x 2.5-3.4 micro meter Pycnidia: on cup margins, common, broadly pyriform, constricted at base, black to red, with red gelatin conidia: 3 x 0.5 micro meter Spot tests: K-, C- & KC+ yellow, P-, UV- Secondary metabolites: thallus with usnic acid, zeorin (visible as tiny needle crystals on surface of older herbarium specimens), accessory isousnic acid and porphyrilic acid, plus unidentified aliphatic acids; apothecia and pycnidia with rhodocladonic acid. Habitat and ecology: on humus-rich soils, occasionally on wood, in mountain woodlands World distribution: arctic to temperate regions in Asia, Europe, North and South America (along the Andes) Sonoran distribution: Sinaloa/Durango border, very rare. Notes: This species is very similar to C. pleurota in morphology and chemistry, but C. pleurota is clearly (coarsely) sorediate rather than merely granulose. Fertile specimens of both species may be corticate so that they may be difficult to distinguish. Highly squamulose specimens are also difficult to interpret. See also the discussions under C. borealis and C. pleurota.