Distribution: N - VG, Frl, Ven (Lazzarin 2000b), TAA, Lomb (Lazzarin 2000b, Brackel 2013), Piem (Matteucci & al. 2013), VA (Gazzano & al. 2009, 2009b), Emil (Fariselli & al. 2020), Lig (Lazzarin 2000b, Watson 2014). C - Tosc, Marc (Nimis & Tretiach 1999), Abr (Nimis & Tretiach 1999), Mol (Nimis & Tretiach 1999, Caporale & al. 2008), Sar. S - Camp (Aprile & al. 2003b, Nimis & Tretiach 2004, Garofalo & al. 2010), Pugl, Bas (Bartoli & Puntillo 1998), Cal (Puntillo 1996), Si (Nimis & al. 1994, Ottonello & al. 1994).
Description: Thallus squamulose, homoiomerous, slightly gelatinous when wet. Squamules brown-black to black, dispersed to crowded, attached by a central point, 0.3-1.2 cm diam., button-like, with an often lobulate to incised margin, not pruinose and not isidiate, attached by a central, compact bundle of rhizohyphae. Apothecia 2-10 or more per squamule, first immersed and urceolate, but soon expanded and clearly lecanorine, to 2 mm across, with a dark reddish brown, concave to flat disc, and a thick, usually smooth thalline margin. Epithecium brownish orange, 5-15 µm high; hymenium colourless, 80-150 µm high, the hymenial gel I+ blue, paraphyses moniliform, 3-4.3 µm thick, the upper cell clearly swollen and to 7 µm thick; hypothecium yellowish, 70-130 µm high. Asci 8-spored, clavate, thin-walled, with an amyloid apical cap. Ascospores 1-celled, hyaline broadly ellipsoid to ellipsoid, 7-15 x 4-10(-12) µm. Pycnidia immersed, globose. Conidia hyaline, ellipsoid, 2-4 x 0.5-1.5 µm. Photobiont cyanobacterial, chroococcoid, of a few cells 8-14 µm diam. surrounded by a gelatinous sheath which is yellowish brown to purple near the thallus surface. Spot tests: all negative. Chemistry: no lichen substances.
Note: on steeply inclined surfaces of limestone and dolomite with periodical water seepage after rain, below the subalpine belt. Some older records could refer to A. moedligense.