Thallus to 5 cm diam., ± closely appressed, thin and papery. Lobes to 2 mm wide, ± flat, contiguous, ± overlapping at the centre; the upper surface brown to green-brown, dark olive-green when wet, mostly smooth or occasionally undulating and slightly pitted, matt or occasionally shiny towards the margins, lacking pseudocyphellae, densely isidiate. Lower surface pale brown, with scattered unbranched pale rhizines. Isidia laminal and marginal, intact and not becoming sorediate, cylindrical, simple becoming branched or coralloid, not inflated, ± smothering older parts of the thallus, initials on newer lobes discrete, ± evenly spaced. Anamorph: not known. Teleomorph: ascomata apothecia, very rare, 2-3 mm diam., the thalline exciple densely isidiate. Ascospores 8-11 × 4.5-6.5 μm, ellipsoidal. Chemistry: lichen products not detected by TLC.