Melanelixia  

Thallus foliose, loosely to moderately adnate, dorsiventral, to 15 cm diam. Lobes plane to shallowly concave, flat, short, the apices rounded, 1-6 mm wide, margins without cilia but in one GB&I species with short hyaline marginal hairs. Upper surface olive-green to dark brown, smooth to rugose, maculate or not, lacking pseudocyphellae, with isidia (sometimes secondarily corticate) or soredia. Upper cortex covered with a pored epicortex (dispersed pored or fenestrations). Cell walls containing isolichenan. Medulla loosely packed, white to pale yellow or occasionally orange in lower parts. Lower surface flat, smooth, dark brown to black; rhizines simple, sometimes with white tips.
Anamorph: conidiomata pycnidia, laminal, immersed. Conidia 5-8 × ca 1 μm, cylindrical to fusiform, hyaline, aseptate.
Teleomorph: ascomata apothecial, laminal, sessile or shortly stalked; disc concave to flat, imperforate, pale to dark brown, the margin commonly sorediate/isidiate. Asci elongate, clavate, Lecanora-type, apically thickened, without an internal apical beak, 8-spored. Ascospores 9-15 × 5-11.5 μm, ellipsoidal to ovoid, hyaline, thin-walled, aseptate.
Chemistry: cortex with a brown coloured pigment but no other compounds; medulla containing depsides (lecanoric and ± 5-methoxylecanoric acids), ± rhodophyscin.