Description

 Thallus: crustose, poorly developed or composed of dispersed warts; areoles: rounded to slightly deformed or irregularly incised, 0.10-0.30 mm in diam., moderately to strongly convex, ecorticate but sometimes with a loose unorganised alga-free layer of various hyphae; surface: greenish or yellowish beige to ochre, dull, esorediate; Apothecia: rounded, rarely slightly irregular in outline, single, sessile with a constricted base, 0.3-0.6 mm in diam.; disc: beige, ochre or orange- to red-brown, sometimes with a faint green tinge, dull, flat to moderately convex, finely white pruinose especially when wet; margin: yellowish beige to ochre (concolorous with thallus areoles, if present), dull, strongly prominent and ±overlapping disc when young, persistent but often ±level with disc in old apothecia, without a parethecial ring; amphithecium: present, with algal cells ±equally distributed in medulla, laterally 40-85(-150) µm wide, basally 45-100(-145) µm wide, composed of hyaline, short-celled hyphae with lumina 1-2 µm wide, corticate; cortex: 15-30 µm wide, usually with an inner layer of periclinal hyphae and external ±anticlinally arranged hyphae with lumina of 1-2(-2.5) µm but sometimes reduced to a layer of periclinal hyphae and an outer gelatinous layer; parathecium: indistinct; epihymenium: sordid greenish ochre to orange-brown, with fine granules (soluble in K), 5-15 µm high; hymenium: hyaline, rarely faintly yellow, or with orange-brown stripes, 30-45(-50) µm tall; paraphyses: simple or weakly branched and anastomosing, hyaline, sometimes with brownish apical cells, with lumina basally 1-1.2 µm wide and apically 1-2 µm wide; subhymenium: hyaline, 20-50 µm thick; hypothecium: hyaline or faintly yellow, (5-)20-75 µm thick; asci: clavate, 8-spored; ascospores: hyaline, simple, narrowly ellipsoid to ellipsoid, (5.5-)6.6-10.9(-13) x (2.5-)3-3.7(-4) µm; Pycnidia: not observed; Spot tests: thallus K-, C-, KC-, P-; Secondary metabolites: ±usnic acid and ±isousnic acid.; Substrate and ecology: often endosubstratal, on bark of conifers; World distribution: North America and Europe; Sonoran distribution: Arizona.; Notes: Lecanora subintricata can be distinguished from L. albellula by slightly smaller, more regularly rounded apothecia, narrower ascospores and a shallower hymenium. In sections, the marginal cortex is usually thicker and of more regular width than in L. albellula. Apothecia with excluded margin may resemble those of L. symmicta, which has broader ascospores. Californian collections of this species may represent a different species.