Synonyms: Biatorina ceramonea A. Massal.; Biatorina proteiformis var. ceramonea (A. Massal.) A. Massal.; Biatorina rabenhorstii (Hepp) A. Massal.; Lecania actaea var. violacea B. de Lesd.; Lecania alborubra B. de Lesd.; Lecania algarbiensis Cout.; Lecania erysibe var. ceramonea (A. Massal.) Zahlbr.; Lecania erysibe var. rabenhorstii (Hepp) Mudd; Lecaniella rabenhorstii (Hepp) Jatta
Distribution: N - VG, Frl, Ven (Lazzarin 2000b), TAA, Lomb, Piem (Clerc & al. 1999), VA (Matteucci & al. 2013), Emil (Fariselli & al. 2020), Lig. C - Tosc, Laz, Sar. S - Camp (Ricciardi & al. 2000, Garofalo & al. 2010), Pugl, Si (Ottonello & Salone 1994, Ottonello & al. 1994, Caniglia & Grillo 2001, 2005, 2006, Grillo & Caniglia 2004).
Description: Thallus crustose, areolate, rather thick, yellowish brown to brownish grey, sometimes delimited by a whitish to pale brown prothallus. Areoles mostly sharply angular, 0.3-2.5 mm wide, flat, the edges often slightly curling upwards, the surface sometimes with 0.05 to 0.2 mm wide granules, epruinose. Apothecia usually numerous, crowded, broadly sessile, round to deformed, up to 0.8 mm across, with a pale yellowish brown to brownish black, occasionally dark-spotted, flat to convex-hemispherical, usually white-pruinose disc, and a thin, smooth to crenulate, whitish, not much raised thalline margin which becomes excluded in old apothecia. Epithecium colourless, mottled pale brown-orange or dark brown; hymenium colourless, (50-)60-75(-85) µm high; paraphyses strongly coherent, simple, 1.5-2 µm thick at mid-level, a few with strongly swollen, 3-6 µm wide apical cells; hypothecium colourless. Asci 8-spored, narrowly clavate, with a K/I+ blue tholus and a central non-amyloid area, Bacidia-type. Ascospores 1-septate, hyaline, not constricted at septum, ellipsoid, straight, thin-walled, 9-13(-16) x 4-5(-7) µm. Pycnidia rare, immersed, the wall colourless but brownish around ostiole. Conidia filiform, strongly curved, 16-22 x c. 0.8 µm. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: on more or less calciferous substrata, including concrete, tiles, cement etc., also in non-natural situations such as on walls in villages; closely related to Lecania inundata.
Growth form: Crustose
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)