White (when dry) foliose lichen primarily occurring on moss over sandstone, but occasionally occurs directly on the rock. Thallus turning greenish when wet, lobes darkened distally, with thick flaky pruina. Soralia marginal and laminal in older thallus material. Soredia appearing isidiate, or at least becoming large and globose in mature specimens. Lower cortex black, shiny, toward center, white and almost intermittent near lobe tips. Rhizines abundant, black, squarrose. Medulla pale yellow, K+Y, KC+Y (darker yellow).