Stereocaulon vesuvianum Pers. var. vesuvianum
Primary thallus minutely squamulose, soon disappearing, pale grey-greenish, secondary thallus composed of branches (pseudopodetia) forming compact tufts, 1-4 cm tall, more or less erect or branched, section circular, pale pink-orange, covered with warts (phyllocladia) producing a coralloid aspect or shield-like, center of phyllocladia dark grey-greenish with a paler margin, pseudopodetia apices sometimes topped off globose piles of soredia, grey-yellowish, hardly ever brown-olive to blackish cephalodia present. Apothecia very rare, dark brown, flat to convex, 0.5-1 mm diam., on lateral branches. Ascospores markedly elongate, colourless, 3-5-septate, 25-35 x 3-4 µm. Paraphyses with thick brown tip. Photobiont: Trebouxioid. C-, K+ yellow, occasionally K+ red, KC- , Pd+ orange. Rare, on more or less acid rocks, usually iron-rich, and also on top of walls within mosses.*