Physcia albinea (Ach.) Nyl.

    Thallus foliose, placodioid, rosette-shaped, 3-8 cmm diam., lobate, lobes 0.5-1 mm wide, indented, margins crenulate, convex, without pruine or little, upper surface not maculate (or little), pale grey, grey-bluish, dull whitish, lower surface pale brown, rhizine simple. Apothecia more or less numerous, sessile, 1-4 mm diam., disc flat, blackish possibly tinged with  blue, without pruine, thalline exciple present, uneven, concolourous to the thallus. Ascospores ellipsoid, pale brown, 1-septate, 14-19 x 7-10 µm. Photobiont: trebouxioid. Cortex: C-, K+ yellow, Pd-; medulla: C-, K-, Pd-. Saxicolous, thermophile, Mediterranean species, on rocks (other than calcareous). Very similar to Physcia stellaris. N.B. Very similar too to Physcia mediterranea, and sometimes considered as synonymous by some authors.