Thallus to 3(-4) cm diam., foliose, rounded to somewhat irregular, rather difficult to distinguish individuals, deeply and broadly lobate, adnate or partly ascending, ± thin, of about uniform thickness, smooth or in part subpustulate, pale to dark olive-green, matt or somewhat glossy, isidiate. Isidia marginal and laminal, numerous, dense (laminal isidia sometimes in darkish spots) at first ± globular, soon elongate to squamiform, concolorous with thallus, simple or slightly branched. Lobes few, rounded to ± elongate, imbricate, 2-4(-10) mm broad, undivided or somewhat lobulate, usually ascending and undulate at margins, margins entire or densely isidiate. Apothecia absent in New Zealand material, in other parts of the the species range, sparse to numerous, laminal, sessile with a constricted base, to 1.6 mm diam., disc plane, red, whitish-pruinose, pruina thin to very thin or disappearing, thalline margin thin, entire, smooth or uneven or ± isidiate, persistent to ± disappearing. Ascospores 4 per ascus, monostichous to distichous, imbricate, fusiform, straight or slightly curved, with acute and sometimes extended apices, (4-)5-6-celled, (28-)30-36 × (6.5-)7-8.5 µm.