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

Thallus: crustose, epiphloeodal, thin, continuous or slightly cracked to rimose areolate, effuse, not clearly delimited surface: white, sometimes with a yellowish tinge, smooth, anatomy: ecorticate, without a distinct medulla; I+ pale red, K/I+ pale red or pale blue, in parts Ascomata: black, sessile or adnate, +round, 0.2-0.6 mm in diam., scattered, with distinct margin when young disc: black, flat to convex, with a smooth or more often uneven surface exciple: dark brown to carbonaceous, closed below the subhymenium, 30-50 µm wide above and 50-70 µm wide basally, I-, K-, without granules pseudoepithecium: dark olive-green to dark brown, reticulate, without granules hymenium: hyaline, 130-150 µm tall, I+ pale red, K/I+ pale red; paraphysoids: with irregularly shaped apical cells up to 5 µm wide, richly branched and anastomosing; some sections with thinner (up to 1 µm) strongly branched paraphysoids, interwoven in the hymenium with the normal ones subhymenium: brown, 35-60 µm thick, I+ pale red, K/I+ pale blue in the upper part; hypothecium: dark throughout, I-, without granules under polarized light asci: cylindrical, 90-130 x 10-12 µm ascospores: hyaline, transversely 14-23-septate, acicular, Patellarioides-type, 65-95 x 2-2.5(-3) µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on oaks or other hardwoods, in humid, rather shaded situations World distribution: Chile and North America Sonoran distribution: Channel Islands of southern California.