Mycoblastus sanguinarius (L.) Norman

    Thallus crustose, thick, surface markedly uneven, granulose to verrucose, more or less cracked, grey-greenish, prothallus hardly visible, grey; medulla whitish, except below apothecia (typically bright red). Apothecia usually numerous, 0.5-2 mm diam., tightly attached to the thallus, plane at first, then convex and sometimes globose, matt black. Ascii cylindrical-clavate, 115-150 x 50-65 µm according to our measures, 1-2-(3 seldom)-spored. Ascospores colourless, medium to very large, thick wall (5 µm), oblong to ellipsoid, multinucleate, 70-100 x 30-50 µm according to literature, 65-90 x 30-45 µm according to our measures. Photobiont: clorococcoid. Cortex : C-, K+ yellow, Pd+ yellow ; medulla ; K+ bright red to carmine below apothecia. Montane or northern trends, on bark of deciduous trees, more seldom on wood or mossy rocks. This species previously has been documented in our prospection area but has not been found since a long time.