Lecanora conizaeoides Nyl. ex Crombie
Thallus crustose, 5-10 cm across, coarsely granular, more or less cracked, slightly powdery, composed of large granules more or less covered with soredia, green-greyish, green-yellowish when moist, greyish tinged green when dry. Apothecia scattered all over the thallus, more or less protruding, 0.5-1 mm diam., disc greenish tinged pink, pale green-ochraceous when moist, pale brown, pale leather-brown when dry, exciple large and thick, irregularly flexuous, crenulate to granular, concolourous to the thallus. Ascospores simple, very broadly ellipsoid, 8-14 x 5-8 µm. Photobiont: Trebouxia. Thallus: C-, K- or seldom pale yellow, Pd+ yellow > rusty, UV+ orange. On nutrient-rich and various acidic substrates, formerly abundant within cities on any kind of acidic substrates due to the high concentration in sulphur dioxide. Rarer since the improvement of air quality in cities and mostly restricted to barks (or wood) of worked conifer timber (Pinus). N.B. The sorediate form is the most frequent (= Lecanora conizaeoides morpho. conizaeoides) but a more scarce form without soredia, Lecanora conizaeoides morpho. variola growing mainly on bark of isolated Pinus may be found. In fact, all intermediate forms may be found. See also Lecanora strobilina of which the thallus is less granulose and Pd-. N.B. Sometimes, the host of Athelia arachnoidea.