Synonyms: Acrocordia conoidea var. macrospora (A. Massal.) B. de Lesd.
Distribution: N - VG, Ven, Lomb, Lig (Lazzarin 2000b). C - Tosc, Laz (TSB 17641), Sar (Rizzi & al. 2011). S - Camp (Aprile & al. 2002, Catalano & al. 2016), Pugl, Cal (Puntillo 1996, Sérusiaux 1998), Si.
Description: Thallus crustose, episubstratic, grey to grey-brown, ecorticate, smooth or faintly rimose, especially around the perithecia. Perithecia black, 0.8-1 mm across, rather prominent, the ostiole not papillose. Involucrellum hemispherical, brown-black, spreading laterally; exciple globose, colourless or pale brownish; hymenial gel I-, K/I-; hamathecium of persistent, slender, sparingly branched or anastomosing, long-celled pseudoparaphyses; periphyses absent. Asci 8-spored, narrowly cylindrical, K/I-, fissitunicate, the apical dome with a broad ocular chamber surmounted by a hemispherical meniscus-like structure. Ascospores 1-septate, not or slightly constricted at septum, the septum thick and the cells equal, hyaline, ellipsoid with rounded ends, 19-29 x 9.5-12 μm, uniseriately arranged in the asci, surrounded by a perispore which appears verrucose in water, smooth in K. Pycnidia rare, black, 0.2-0.3 mm in diam. Conidia acrogenous, ellipsoid, simple, colourless. Photobiont trentepohlioid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: an apparently Mediterranean-Atlantic, mild-temperate species ranging from Macaronesia to Norway, found on base-rich or weakly calciferous siliceous rocks in sheltered situations below the montane belt. Certainly rare in Italy.
Growth form: Crustose
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)