Distribution: N - VG, Ven (Nascimbene 2004, Nascimbene & al. 2005b, 2006c), Lomb (Jatta 1909-1911), Piem (Isocrono & al. 2004). C - Tosc, Laz (Munzi & al. 2013), Sar (Zedda 2002, 2002b). S - Camp (Aprile & al. 2003b), Pugl, Cal (Puntillo 1996), Si (Nimis & al. 1994, Ottonello & Puntillo 2009, Ottonello & al. 2011).
Description: Thallus crustose, thinly episubstratic, spreading, continuous to cracked-areolate, pale yellowish green to dark olive-green, sometimes evanescent. Apothecia biatorine, sessile, round, (0.4-)0.6-1.5(-2) mm across, usually scattered, clearly constricted at base, with an orange-yellow to yellow-red, shallowly concave then convex, epruinose disc and a paler, flesh-colored, prominent, entire or flexuose, persistent proper margin. Proper exciple colourless, 40-60 µm thick, paraplectenchymatous, composed of globose to angular cells with an outer layer of weakly vertically oriented hyphae; hymenium colourless, I+ blue, then rapidly dirty green and finally red-brown; paraphyses sparingly branched in upper part, 1.5-2.7 µm thick at mid-level, the apical cells c. 4.5 µm wide; hypothecium colourless. Asci 8-spored, unitunicate, thin-walled, narrowly cylindrical, without an amyloid ring around the apical pore, Catillaria-type, with uniseriate ascospores. Ascospores 1-septate, hyaline, fusiform to fusiform-ellipsoid, (6-)9-11(-14) x 2-3.5(-4.5) µm. Pycnidia more or less immersed, yellowish brown, the wall colourless. Conidia ellipsoid, 3-4(-5) x 1.3-2(-2.5) µm, not constricted in the middle. Photobiont trentepohlioid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: a mild-temperate to humid subtropical lichen found on bark and epiphytic liverworts in semi-natural, old, humid forests at low elevations; mostly Tyrrhenian in Italy. It is included in the Italian red list of epiphytic lichens under the “Least Concern” category (Nascimbene & al. 2013c).
Growth form: Crustose
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)