Description: Thallus crustose, thinly episubstratic, white or pale grey, continuous or cracked. Ascomata unknown. Pycnidia black, 0.2-0.6 mm across, 0.2-0.5 mm high, conical, with a globose base tapering into a narrow neck. Conidia pyriform-ellipsoid, with a truncate base, 5.5-6.5 x 2.5-3 µm, sometimes extruded as a long, white cirrus. Photobiont trentepohlioid. Spot tests: all negative. Chemistry: no lichen substances.
Note: a recently-described species, hitherto known only in the sterile state, with macropycnidia and conidia similar to those of A. polypori, but much larger. So far recorded only from a few sites rich in old-forest lichens in the United Kingdom, but perhaps more widespread. To be looked for in the most humid parts of Tyrrhenian Italy.
Growth form: Crustose
Reproductive strategy: mainly asexual, by thallus fragmentation
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)