Distribution: N - Piem (Ravera & al. 2016b). C - Tosc (Ravera 2006b).
Description: Thallus crustose, endosubstratic, poorly evident, probably non-lichenized. Perithecia black, numerous, scattered, subglobose, circular or ellipsoid, 0.09-0.23 x 0.09-0.11 mm. Perithecial wall of textura intricata, black, not continuous below the hamathecium; involucrellum dimidiate, dark reddish brown, K-, c. 20-25 μm thick, intermixed with c. 3 μm thick, dark hyphae, the amorphous pigment localized in the cell wall; exciple c. 7-10 μm, brown in upper part, colourless, to 5 μm thick and scarcely discernible at base, K-; pseudoparaphyses absent, but periphysoids present in the ostiolar region, branched, 5-10 x 1-1.5 μm, septate. Asci 8-spored, bitunicate, obclavate-obpyriform, with a typically fissitunicate dehiscence; endotunica gradually thickened to apex; ocular chamber rounded, the obconical structure in tholus I+ blue. Ascospores 1-septate, hyaline, constricted at septum, with a short upper cell and an elongate, pointed lower cell (tadpole-shaped), 11.7-14.8 x 3.6-4.9 μm, non-guttulate; mature spores often with a slight median constriction in the lower cell; perispore indistinct. Photobiont probably absent. Spot tests: all negative. Chemistry: without lichen substances.
Note: a recently-described, most probably non-lichenised species which grows as a pioneer on the smooth bark of twigs, especially of Castanea; hitherto known only from Tuscany and Piemonte, but in past perhaps confused with A. salicis.
Growth form: Fungus
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)