Opegrapha gyrocarpa Flot.
Gyrographa gyrocarpa (Flot.) Ertz & Tehler
Thallus crustose, sometimes mosaic-forming, leprose, granular, moderately thick, more or less cracked, brown-yellow, brown-red, rusty, brown-pink, brown-orange, brown-chocolate, etc. with areas paler, pinkish, tinged orange or yellow, margin delimited by a black prothallus, mainly visible in case of contact with other species, covered with soralia, up to 1.5 mm diam., lemon-yellow, yellowish, yellow-orange, ochre-yellow, grey-pinkish, in some cases confluent and then generating a thick verrucose matt. Thallus often sterile but sometimes with small scattered lirellae, more or less gyrose or in piles, 0.5-1 mm long, black. Ascospores elongate, ellipsoid, 3-septate, 18-25 x 3-5 µm. Soralia: C+ red, KC+ red, K-, Pd-. Not especially maritime, frequent on damp vertical walls of shaded siliceous rocks and even more frequeltly on old walls. Not to be confused with some morphs of Belonia nidarosiensis which are C- and may well coexist. Most often this species is leaving with other close species easily mistaken like Opegrapha saxigena of which the thallus is more dark-brown, without soredia and Opegrapha (Enterographa) zonata that is sorediate, soredia lilac or pale, C-.*