Lepra melanochlora (DC) Haffelner =Pertusaria melanochlora (DC) Nyl.

     Thallus crustose, relatively thick and strongly fixed on its substrate, up to 10-12 cm in diameter, with folds forming streaks arranged radially especially towards the margin and also concentric folds of growth, greyish, dark gray, lead gray, typically with greenish or bronze tinges; covering from the center with large cylindrical isidia forming papillae or concolorous warts with the thallus but at the whitish apex showing the medulla by abrasion, the apex of these papillae may also be covered with whitish soredia, hypothalle often present, radiated and a little cockade darker. Apothecia 1-1.5 mm in diameter, rare, 1-5 at the top of fertile papillae, blackish. Asci with one spore. Colorless, thick-walled, broadly elliptical spores, 180-250 x 70-150 µm. Thallus: C-, K + yellow to red-orange, KC- fleeting violet, P + red-orange, UV-; bitter taste like Lepra amara. Rare saxicolous species with mountainous tendencies but reported from the seaside in Brittany, coming on not very acidic and a little schistose rocks NB Species quite similar to Lepra  pulvinata which is corticole and Pertusaria mammosa also saxicolous but with smaller warts, no bitter and different in chemistry.