Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.

Thallus: crustose, areolate or rarely continuous, 0.1-0.5 mm thick; prothallus: present, black to grayish black, rarely found at individual areoles surface: yellowish gray to grayish white, strongly verruculose to nearly isidia-like, dull Apothecia: semi-immersed to sessile, slightly constricted at base, 0.5-0.8 mm in diam. disc: black, plane to weakly convex, epruinose margin: distinct, up to 0.5 mm thick, persistent exciple: green to greenish gray, sometimes brown, without algal cells parathecium: hyaline, sometimes with crystals epihymenium: green, greenish gray to olive, rarely with crystals (if damaged ?) hymenium: hyaline, 55-70 µm tall, not inspersed; paraphyses: simple, rarely anastomosing or branched, slightly thickened apically hypothecium: hyaline, partly strongly filled with crystals asci: clavate, lecanoral, 8-spored ascospores: hyaline, simple, ellipsoid, 10-13 x 6-7 µm; wall: thick and smooth, not halonate Pycnidia: globular, with Vobis-type III conidiophores conidia: filiform and slightly curved, 14-20 µm long Spot tests: thallus surface K- to K+ yellow, C- to C+ yellowish red, P- to P+ yellow Secondary metabolites: 2,5,7-trichloro-3-O-methylnorlichexanthone, 5,7-dichloro-3-O-methylnorlichexanthone, atranorin, chodatin, demethylchodatin, isoarthothelin (= 2,5,7-trichloronorlichexanthone), and thiophanic acid (= 2,4,5,7-tetrachloronorlichexanthone). Substrate and ecology: usually on non-calciferous rocks, rarely on bark World distribution: Africa, Australasia, Europe, North and South America Sonoran distribution: from near sea level to upper montane areas in Arizona, southern California, Baja California and Sinaloa.