Thallus foliose, heteromerous, dorsiventral, lobate or ± squamulose, or ± areolate or ± granular, orbicular to spreading, loosely or closely attached, often with a prominent black or blue-black (rarely buff or pale) marginal prothallus of projecting, felted rhizines. Lobes variable, broad and rounded to laciniate, to microphylline and ± lobulate-squamulose. Upper surface dark bluish-green, plumbeous to fawnish or brownish-grey or olivaceous, smooth or wrinkled-plicate, matt, glossy or ± scabrid or pubescent, with or without soredia, isidia or phyllidia, margins entire to phyllidiate or sorediate or incised-crenulate. Medulla white. Photobiont blue-green, . Lower surface tomentose or ± rhizinate, usually pale. Rhizines felted, silky, blue-black to whitish, often projecting beyond margins as a byssoid prothallus. Apothecia sessile to subpedicellate, rounded, biatorine, with a pale proper margin, lacking a thalline margin. Hymenium 100-120 µm, tall, colourless. Paraphyses numerous, compacted, simple, rarely slightly branched at apices c. 2 µm thick, slightly thickened apically. Asci clavate to subcylindrical, 8-spored. Ascospores uniseriate, simple, colourless, oblong to ellipsoid, often apiculate at one or both ends, epispore often indistinct or absent.