Lecanora compallens Herk & Aptroot
Thallus crustose, continuous, more or less immersed, whitish-glaucous, with numerous whitish to grey-glaucous warts, 0.1-0.2 mm diam. at their base, progressively covered with punctiform soralia, confluent to form an almost continuous soralia crust extending to the whole thallus, yellow-greenish with mint-green zones. Apothecia unknown. Photobiont: Trebouxia. Thallus: C-, K-, KC-, Pd- ; soredia : C-, K+ dull yellowish, Pd-. On well-lit barks of isolated trees, notably ornmental trees. N.B. Lecanora strobilina is a very close species with identical chemical reactions, but smaller and with apothecia (aborted -or 'embryo' - of apothecia were present on the specimen presented here). See Lecanora expallens, which is C+ yellow-orange. See also the sterile Psilolechia lucida form, but this species is seldom found on trees and even less frequently on bark.
N.B. Lecanora expallens, is very similar and differs only by its chemistry: C + yellow-orange, to the point that some authors group the two species together!