Enterographa zonata (Körber) Källsten ex Torrente & Egea

    Thallus crustose, more or less thick, minutely warted or cracked, brownish, brown-chocolate, quite often grey-brown when immature and fresh, with pale lilac or violet tinge, prothallus black, conspicuous in case of mosaics, covered with abundant punctiform isolated soralia, 0.5-1 mm diam., pale brown, brown-violet, much paler when eroded or old and then contrasting with the dark thallus. Apothecia rare, only in places devoid of soralia, rounded or lirelliform, 0.2-0.4 x 0.1-0.3 mm  long, black, not divided and unbranched, disc slit-shaped, black. Ascospores fusiform, pointed at apices, 6-7-septate, 24-28 x 4-6 µm. Chemical spot tests negative. Rather rare, on damp shaded rocks, old damp and shaded walls. Most often in combination within mosaics with Opegrapha gyrocarpa  that is brown-orange or yellow-lemon and of which the soralia are less delimited and C+ red, much less frequently associated with Opegrapha saxigena of which soralia are absent from the dark thallus.*