Thallus: foliose, continuously forming rosettes, 3-10 cm wide, loosely adnate, lobate lobes: irregular, broad (5-17 mm wide), elongate; apices: usually subrotund, entire or crenulate, sometimes ascending upper surface: gray to grayish brown, dull, usually strongly pubescent; isidia and soredia absent.but frequently with regeneration squamules marginally or along cracks medulla: white photobiont: the cyanobacterium Nostoc lower surface: pale brown to yellow-brown or whitish, densely tomentose, white papillate (scarcely to densely) Apothecia: common, on lower surface at tips of lobes, orbicular, up to 15 mm diam., cup-shaped, sessile; dorsal surface: tomentose, coarsely scabrid and foveolate-reticulate; margin: prominent with thalloid rim; disc: dark brown; exciple: hyaline or light brown, 20-30 µm thick; epithecium: brown or brownish yellow; hypothecium: hyaline asci: 8-spored ascospores: fusiform, 3-septate, 21-24 x 4-6 µm; wall: thin, light brown Pycnidia: marginal, immersed, punctiform, 0.15-0.20 mm diam. conidia: rod-shaped, 4-5 x 1-2 µm Spot tests: upper surface: K-, C-, KC-, P-; medulla K-, C-, KC-, P- Secondary metabolites: none detected. Habitat and ecology: on acidic rocks among mosses and tree trunks in moist canyons at mid- to high elevations, most common in spruce-fir regions World distribution: South Pacific and Northern Hemisphere, where it occurs in boreal and north temperate regions and extends south along the west coasts in maritime influenced regions Sonoran distribution: central and eastern Arizona.