Thallus: crustose, thin to thick, continuous, when well developed of ±fused granules forming a warted or almost subsquamulose, rimose or areolate crust surface: gray- or brown-green, sometimes ±dissolved into finely granular, pale green soredia Apothecia: flat or slightly convex, 0.2-0.6(-0.8) mm in diam. disc: dull black or sometimes ±brown or pale blue (then often piebald), epruinose margin: distinct, level with or raised above disc in young apothecia, usually persistent, dull, concolorous with disc or (particularly in lower part) paler exciple: laterally 30-50 µm wide, without crystals, green-brown to purplish brown above (mixture of brown, K+ purplish, N+ orange and green, K-, N+ purple pigments), darkest in apothecial crown and along edge, fading below to colorless or ±pale brown epithecium: olive-green to blue-green (K-, N+ purple), sometimes with spots of brown (K+ purplish, N+ orange), without crystals hymenium: hyaline, 35-70 µm tall; paraphyses: 1.5-2 µm wide in mid-hymenium; apices: ±clavate or some only slightly or not at all swollen, 2-6 µm wide hypothecium: ±orange-brown (K+ olivaceous brown or K+ intensifying), sometimes almost colorless asci: clavate, 8-spored, more or less Bacidia-type but with a rather wide axial body ascospores: hyaline, 3- to 7-septate or indistinctly septate acicular, clavate, or long-bacilliform, straight or slightly curved, 13-42 x 1.5-2.5 µm Pycnidia: ±immersed in thallus, colorless, 100-200 µm in diam. conidia: filiform, curved to sigmoid, 0-3-septate, 20-35 x c. 1 µm Spot tests: all negative Secondary metabolites: none detected. Habitat and ecology: on acid or slightly basic rocks in shade, also on anthropogenic substrates such as bricks or tiles, from almost sea level to 2000 m World distribution: Europe, North America, and Asia, possibly occurring elsewhere Sonoran distribution: known from a few scattered localities in Sonora, Arizona, but southern California and probably often overlooked.