Lecanora symmicta (Ach.) Ach.
Thallus crustose, but sometimes leprose, to 3-10 cm across, or in small patches, rather thin, granulose or areolate, pale green-yellowish, pale greyish, prothallus absent or indeterminate. Apothecia abundant, 0.5-0.8 mm diam., scattered or clustered, disc flat becoming slightly convex, pearly, pale ochre-yellow, beige-yellowish, darkening when old, exciple thin soon excluded. Utriform asci, 45-55 x 15-18 µm according to our measurements, with 8 spores. Simple spores, elliptical, 9-15 x 4-5 µm according to the literature, 10-16 x 3.5-5.5 µm according to our measurements.Photobiont: Trebouxia. C- or seldom C+/- orange, K-, KC+/- yellow, P-d, UV+ orange. Common, on acid barks (on Pinus occasionally), on dead ecorticate trees and on timber and timber works, wood poles near the seashore.
N.B. Resembles to Lecanora polytropa which is seldom found on timber works and poles near the seashore, and to Lecanora varia that shares the same habitat but with different apothecia, less yellowish, more sessile and with a crenulate and wavy exciple. Also looks a lot like Lecanora strobilina which has a bit smaller spores and is C-.