Thallus: crustose, effuse, areolate, rimose-areolate or minutely and irregularly granular-warted or scurfy granular, but granules never discrete, rarely powdery, thin , up to 0.3 mm thick areoles: subangular, plane, contiguous, 0.2-0.8 mm across surface: pale gray, gray-green to pale brown often overgrown by green algae, dull, epruinose, sometimes leprose-like, not discolored when wet and only somewhat translucent; edges concolorous with the rest cortex: not developed, corticoid structures not found, the thallus filled with algae throughout medulla: indiscernible; algal layer: cells globose, 5-15 µm in diam. Apothecia: sessile or adnate, scattered to crowded, sometimes clustered, 0.2-0.4(-0.6) mm in diam. disc: pale beige, pale orange-pink, or pale to dark reddish brown, often some what piebald, flat to moderately convex, epruinose, when wet becoming darker with dark pigmented edge margin: colorless, or pale to dark pinkish brown amphithecium: absent parathecium: colorless or upper (outer) part pale to dark pinkish brown and K+ purple, with narrow, conglutinated hyphae often with expanded lumina (up to 5-7 x 2-2.5µm), sometimes with algae reaching the parathecium below epihymenium: colorless to slightly pinkish-brown hymenium: hyaline, (35-)40-45(-50) µm tall, colorless, or pale gray and K+ purple in dark apothecia; paraphyses and asci conglutinated in a hyaline gelatinous matrix; paraphyses: simple, c.1.5 µm wide in mid-hymenium cells, the apices up to 4 µm in diam., colorless or rarely brownish pigmented; hypothecium: colorless or pale straw-colored asci: cylindrical to clavate, Bacidia-type, 25-40 x 7-12 µm, 8-spored ascospores: hyaline, (1-)3(-5)-septate, narrowly fusiform, (11-)14-21(-28) x 2.5-3 µm Pycnidia: immersed, 50-80 µm in diam., pale, sometimes reddish-brown around the ostiole; conidiogenous cells: elongate, often abundantly present but easily overlooked conidia: filiform, strongly curved, 10-19 x 0.8-1.2 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on deeply shaded limestone rocks, mainly in dry underhangs and deep crevices World distribution: central and western Europe and northwestern Mexico Sonoran distribution: only known from one locality in Chihuahua. Notes: Lecania cuprea is characterized by its often piebald colored apothecia, its ±dark margin, its mostly 3-septate, narrowly fusiform ascospores, and its granular-warted or scurfy granular thallus, and it occurs on shaded calcareous rocks. The only species in the Sonoran region, with which it might be confused, is L. coeruleorubella (see notes under that species). According the description of Bacidia king manii, it could also be confused with that species; however, Stefan Ekman has established that B. kingmanii belongs to Lecidea (see treathment of Lecidea and Bacidia), as its ascospores are simple, and so there be no cofusion with that species.