Melanelia disjuncta (Erichsen) Essl.

    Thallus foliose, rosette-forming, to 5-8 cm diam., lobes appressed, 0.5-1.5 mm wide, flat or convex, apices wavy and upturned, upper surface dark brown, sometimes almost black, pseudocyphella definite as small white dots at lobe apices, surface soon covered from the center with minute globose isidia, forming clusters, greyish and globose, lower surface brown-black with simple rhizines. Apothecia very rare, 2-4 mm diam., sessile, disc concave, exciple sorediate or rough. Ascospores simple, ellipsoid, 9-12 x 5-7 µm. Photobiont: trebouxioid. Medulla: C- or seldom C+ pink, KC+/- pink, K-, Pd-. Rare, montane trends, on exposed siliceous rocks, preferentially more or less vertical. Easily confused with Melanelixia fuliginosa subsp. fuliginosa of which medulla is C+ red, devoid of pseudocyphella towards the lobe margins and blacker. Shares also a general common aspect with Xanthoparmelia verruculifera that is maritime (as other similar Xanthoparmelia) and with larger isidia.*