Thallus lobate, closely attached, to 4 cm diam., corticolous and saxicolous. Lobes sublinear, crowded, 1-3 mm wide, to 20 mm long subdichotomously branched, apices incised, margins entire, axils sinuous. Upper surface smooth, pale greenish-grey, subpruinose at margins, becoming cracked centrally, often appearing pinkish, sorediate. Soredia in coarse, erumpent, laminal pustules or coralloid clusters, appearing glomerulate and somewhat isidiate. Lower surface black, densely rhizinate. Rhizines black, dichotomously branched. Apothecia not seen. Chemistry: Cortex K-; medulla K+ reddish, C-, Pd- or ± orange. Lichexanthone (UV+ golden yellow), colensoinic, norcolensoinic, 4-O-demethylphysodic, physodic, and lividic acids rarely protocetraric acid and, when pigmented, skyrin.