Thallus: crustose, poorly developed or granular-warted with areoles often coalescing to form a scurfy or rimose crust areoles: (weakly to) strongly convex, 0.10-0.25 mm in diam., ecorticate but sometimes with a loose unorganised algal free layer of various hyphae surface: greenish to yellowish gray, dull, sometimes covered with terpenoid crystals, esorediate Apothecia: rounded or slightly irregular in outline, rarely single, mostly densely crowded, sessile with a weakly constricted base, 0.30-0.40(-0.90) mm in diam. disc: yellowish ochre to orange-brown, often with a pinkish hue, flat to moderately or rarely strongly convex, dull, finely white pruinose margin: white, pale gray or more rarely of same color as the thallus, weakly prominent, persistent or excluded, dull, without a parathecial ring amphithecium: present, with an algal layer, laterally 50-100 µm, basally (45-)60-180 µm wide, filled with small brownish granules (soluble in K), irregularly entangled, short-celled hyphae with lumina 1.5-2.0 µm wide, without a true cortex parathecium: hyaline, 15-45 µm wide epihymenium: greenish ochre to orange-brown, granular granules (soluble in K), 5-15 µm high hymenium: hyaline or rarely pale yellow or ochre, (35-)40-50 µm tall; paraphyses: simple or weakly, rarely moderately branched and anastomosing near base of hymenium, with lumina basally 0.7-1 µm wide and apically 1-1.5 µm wide; subhymenium: hyaline, 30-65 µm thick; hypothecium: hyaline or pale yellow, 35-135 µm thick asci: clavate, 8-spored ascospores: hyaline, simple, narrowly ellipsoid, (8.5-)10.6-12.4(-16.5) x (3-)3.3-3.8(-4.5) µm Pycnidia: not observed Spot tests: thallus K-, C-, KC-, P- Secondary metabolites: usnic acid, decarboxysquamatic acid and ±zeorin. Substrate and ecology: sometimes endosubstratal, mostly on twigs and pine scales, more rarely on trunks in lowland coastal regions World distribution: North Africa, North America and SW Europe Sonoran distribution: Southern California, Baja California and Baja California Sur Notes: Lecanora strobilina is closely related to L. americana, L. confusa, L. perconfusa and L. substrobilina. Diagnostic features are the content of decarboxysquamatic acid and comparatively small apothecia, which tend to exclude the thalline margin and become more or less biatorine in appearance. From L. confusa it can further be distinguished by narrower ascospores.