Thallus grey-white to creamy, matt, thin, smooth or encrusting epiphytes on bark, spreading, to 10 cm diam., over epiphytic bryophytes and ferns, also directly on bark. Apothecia to 2.5 mm diam., sessile, constricted at base, plane or becoming subconvex, distinctly marginate, discs and margins concolorous, rusty brown, older apothecia often blackened, with rust-brown granular pruina. Excipulum biatorine. Hypothecium colourless to brownish c. 50 µm tall. Hymenium colourless 180-220 µm tall, covered with brown anthraquinone crystals. Asci and paraphyses as in genus description. Ascospores 1 per ascus, colourless, muriform, ellipsoid, (90-)100-140 × 30-50 µm.