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

Life habit: lichenized areoles: contiguous, flat, irregular in shape, 0.1-0.5 mm in diam. surface: red to rusty red (due to iron oxide), or ochre, rarely black in very exposed habitats, smooth to rough; cortex: 10-25 µm thick photobiont: primary one a chlorococcoid green alga, secondary one absent; algal layer 60-70(-120) µm thick disc: black, flat, dull, epruinose margin: black to rusty, persistent, dull to shiny exciple: brown to dark brown peripherally, brown internally, 30-80 µm wide, with hyphae 3-4.5 µm in diam.; epihymenium: pale gray to dark gray-green, 10-15 µm thick hymenium: hyaline, 65-125 µm tall, I+ orange; paraphyses: branched and anastomosing, c. 2 µm wide below, 2.5-4 µm wide apically; subhymenium: hyaline, 15-25 µm thick; hypothecium: dark brown, 60-70 µm thick Spot tests: cortex and medulla K- (or K+ orange), C-, KC-, P- (or P+ orange) Substrate and ecology: in open, humid habitats on granites, schists and other acidic rocks (especially those rich in iron) World distribution: bipolar and extending into the tropics in alpine areas Sonoran distribution: alpine and upper montane in central and eastern Arizona. lobes: elongate, linear to somewhat shorter and more rounded upper surface: pale brown to brown, olive-brown or blackish-green, usually with +conspicuous marginal, linear pseudocyphellae upper cortex: paraplectenchymatous lower cortex: paraplectenchymatous lower surface: almost white to tan or pale brown, moderately to rather sparsely rhizinate; rhizines: usually concolorous with the lower surface, simple or sparsely furcate Geography: montane temperate to tropical, endemic to North America Substrate: bark (especially conifers) or wood.