Distribution: C - Tosc, Mol (Nimis & Tretiach 2004, Caporale & al. 2008), Sar (TSB 13045). S - Pugl (Nimis & Tretiach 1999), Cal (Puntillo 1996), Si (TSB 17355).
Description: Thallus crustose, thinly episubstratic, continuous or rarely rimose-areolate, usually poorly developed, whitish, sometimes with a pinkish or brownish hue, without a distinct prothallus. Apothecia lirelliform to almost rounded, 0.5-1.2 x 0.3-0.6 mm. simple or sparingly branched, sessile, more or less isolated, black, with an enlarged, often bluish-pruinose disc and a somehow raised, black proper margin. Proper exciple black, carbonized, continuous below the hymenium; epithecium brown-black, 30-50 µm high; hymenium colourless, 50-90 µm high, I+ reddish; paraphysoids branched and anastomosing, c. 1 µm thick, the apical cells hardly swollen; subhymenium brown, well-delimited, 30-60 µm high; hypothecium black, carbonized. Asci 8-spored, clavate, the inner layer of endoascus amyloid in upper part, with a ring visible around a small ocular chamber, Varia-type. Ascospores 4-5(-6)-septate, hyaline turning pale brown when overmature, broadly fusiform, 17-25 x 5-7 µm, with a 1.5-2 µm thick, gelatinous perispore. Pycnidia black, immersed. Conidia straight or slightly curved, 3-6 x 0.5-1.2 µm. Photobiont trentepohlioid. Spot tests: thallus K-, C-, KC-, P-. Chemistry: without lichen substances.
Note: a mild-temperate to Mediterranean-Atlantic species found on steeply inclined faces of calciferous rocks near the coast, in rather shaded and humid situations. The record from Molise, in the mountains, is exceptional.
Growth form: Crustose
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)