Thallus crustose, grey or brown or olivaceous, with a distinct marginal prothallus. Photobiont green, ?. Apothecia lecideine, black or brown-black. Epithecium red-brown, hymenium colourless. Exciple with a brown, sometimes very thick marginal part and an unpigmented innner part. Paraphyses simple or dichotomously branched, with slightly thickened apical cells. Hypothecium ± pale brown or colourless. Asci sub-cylindrical or clavate, 8-spored with a narrow amyloid tholus. Ascospores simple, colourless, ellipsoid-oblong, often curved, thick-walled. Pycnidia crateriform, semi-immersed, brown. Conidia ellipsoid-oblong 2.5-5 × 1.2-2 µm.