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Description type:Original description 
Description:Thallus crustose, often superficial, poorly developed and inconspicuous, thin, rimoseareolate or consisting of dispersed warts, yellowish white to greenish or greyish, frequently sparse on a black prothallus. Apothecia lecanorine, disciform, sessile at first to slightly constricted at base with age, occurring singly or clustered in groups of 2-4 (-5), 0·2-0·5 mmdiam; disc moderately concave, flat to slightly convex, mostly epruinose, pale yellowish to greyish, often almost black. Apothecial margin level with disc to prominent, persistent, smooth, entire, rarely flexuose, epruinose, paler than the disc, concolorous with thallus. Amphithecium laterally 35-75 µm, basally 75-115 µm thick, corticate with a continuous and dense algal layer, c. 50 µm. Amphithecial cortex distinctly delimited, sometimes ±uniform in thickness to thickened at the base, laterally 12-25 µm, basally 20-50 µm thick, hyaline to pale brownish, consisting of strongly gelatinized, anticlinally arranged hyphae, with small yellowish to brownish granules (Pol+), soluble in K, insoluble in N. Parathecium indistinct, hyaline, without crystals (Pol-), gelatinous, 10-12 µm thick. Epihymenium shades of pale yellowish brown to olivaceous grey, granules small (Pol±), superficial, sometimes scanty, soluble in K, insoluble in N, K+ olive green to yellowish blackish, N± reddish. Hymenium hyaline, clear, 40-70 µm high. Subhymenium indistinct, hyaline, 12-25 µm high. Hypothecium not well developed, hyaline, with oil droplets, 12-20 µm high. Paraphyses simple to often weakly branched in uppermost part, slightly expanded apically, tips mostly brownish to blackish pigmented. Asci Lecanora-type, clavate to cylindrical, 8-spored, rarely with 12 spores. Ascospores hyaline, simple, broadly ellipsoid, 6-9 — 5-7 µm. Pycnidia not seen.
Chemistry. Thallus and apothecia K-, C-, Pd-. Usnic acid detected and an unidentified substance with Rf class 6, spot pale greyish yellow-green and UV+ pinkish before and after charring (epanorin?).
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