Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: crustose, thick (usually thicker than 0.5 mm), areolate areoles: very small, <0.2 mm (usually) wide surface: white, yellowish white or yellowish green, with small soredia or with blastidia Apothecia: on thallus, 0.9-1.6 mm in diam. disc: black margin: black, lecideine, distinct (from the beginning) exciple: pale brown, up to 50 µm wide, without algal cells parathecium: yellowish to reddish brown, without crystals epihymenium: blackish, bluish or brownish green or olive brown hymenium: hyaline, (55-)60-80 µm tall, not inspersed; paraphyses: simple, rarely anastomosing or branched, slightly thickened apically hypothecium: brown asci: clavate, lecanoral, 8spored ascospores: hyaline, simple, broadly ellipsoid or ellipsoid, 10-17 x 6-10(-11) µm; wall: thick and smooth, multi-layered, not halonate Pycnidia: not seen Spot tests: thallus surface K+ pale yellow or K-, C+ orange, KC+ orange, P+ pale yellow or P- Secondary metabolites: 2,5,7-trichloro-3-O-methylnorlichexanthone, atranorin, isoarthothelin (= 2,5,7-trichloronorlichexanthone), or thiophanic acid (= 2,4,5,7-tetrachloronorlichexanthone). Substrate and ecology: wood (rarely) or usually non-calciferous rock World distribution: Europe and Northern America Sonoran distribution: southern California and Sonora.