Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: continuous or slightly cracked to areolate, effuse, thin, mostly epiphloeodal surface: white to grayish white anatomy: up to 80 thick, without a differentiated medulla, I+ pale red or blue, K/I+ deep blue Ascomata: black, scattered, adnate to sessile with +constricted base, +round to often somewhat irregular in outline, often oval or sublobulate, +immarginate, +shining, 0.2-0.7 mm in diam., disc: black, plane then convex, uneven, epruinose exciple: laterally well-developed, dark red-brown, closed below the subhymenium or rarely open, up to 40 µm wide at the top and 125 µm wide at the base, I+ reddish, K/I+ deep blue pseudoepithecium: dark brown, reticulate hymenium: hyaline, 75-110 µm tall, I+ pale red or blue in the inner part, K/I+ pale blue; paraphysoids: with apical cells not thickened, richly branched and anastomosing subhymenium: pale to dark brown, variously developed, up to c. 150 µm thick, I+ reddish or blue, K/I+ deep blue asci: narrowly clavate, broadest near apex, 70-100 x 11-13 µm ascospores: hyaline, +acicular, Dryina-type, 70-77 x (1-)2-3 µm, but +inclined to completely fragment into individual cylindrical part-spores; part-spores: notably rectangular or cuboid, (2-)3-8 µm long Pycnidia: immersed or semi-immersed in the thallus, punctiform, globose or subglobose, up to c. 150 µm tall and 140 µm wide; wall: apically brown, hyaline to pale brown basally conidia: straight, 3-5 x 1-1.5 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on bark, especially of oaks, in the coastal hills to submontane belt World distribution: Europe, Asia and North America Sonoran distribution: southern California.