Thallus rather loosely attached, to 8 cm diam., corticolous. Lobes dichotomously branched, margins entire, apices truncate, axils deeply sinuous. Upper surface smooth, matt, pale greenish-grey or whitish, faintly maculate (X 10 lens), sorediate, without isidia. Soredia in terminal or subterminal, capitate soralia, grey or blackened, granular. Lower surface black, rhizinate to margins. Rhizines black, dichotomously to squarosely branched, often projecting beyond margins. Apothecia not seen. Chemistry: Cortex K+ yellow; medulla K-, C+ orange KC+ orange-pink, Pd-. Atranorin, barbatic, 4-O-methylbarbatic (tr.), obtusatic (tr.), and norobtusatic (tr.) acids.