Lecanora intricata (Ach.) Ach.
Thallus crustose, areolate, areoles flat, most often contiguous, areole margins crenulate or indented, yellow-greenish, grey-yellowish, prothallus when present, blackish. Apothecia numerous, 1-2 per areole, 0.5-1 mm diam., immersed or sessile, not constricted at the base, discs concave, then flat to slightly convex, emerald-green to dark green, brown-green, exciple slightly erumpent, flexuous, potentially excluded when old. Ascospores simple, ellipsoid, 10-14 x 5-7 µm. Photobiont: Trebouxia. Thallus: C-, K+ pale yellow, hardly visible, KC+ yellow, Pd-. Not especially maritime, and even montane, although found in various places on siliceous rocks from the xeric supralittoral zone. Not to be confused with the much more common Lecanora polytropa of which the areole margins are smooth and the apothecia more protruding, less dark green. Also, not to be confused with Lecanora sulphurea.*