Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.

Thallus: foliose, 2-5 cm in diam., adnate, subdichotomously to irregularly lobate lobes: irregular, elongate, +plane, separate, sometimes crisped, 3-5 mm wide, 100-120 µm thick; apices: rotund, entire to irregularly cut and isidiate, occasionally upturned upper surface: brown to medium gray, shiny, smooth isidia: scattered to dense, usually laminal but sometimes marginal, granular to cylindrical to lobulate, simple or branched, concolorous with the thallus or darker internal anatomy: with upper and lower cortices consisting of a single layer of irregularly isodiametrical cells 7-14 µm in diam., internally with loosely interwoven chains of Nostoc and hyphae lower surface: pale to medium brown, wrinkled, with dense white tomentum of cylindrical hairs up to 1 mm long Apothecia: infrequent, laminal, sessile, 3-4 mm wide disc: light brown to dark red-brown, concave to plane to convex margin: thalline, concolorous with the thallus, entire or isidiate exciple: euparaplectenchymatous, 45-70 µm centrally hymenium: hyaline below and thinly brown above, 160-180 µm tall; paraphyses: unbranched, c. 1.5 µm wide, slightly inflated apically; subhymenium: pale yellow, 45-60 µm thick asci: cylindrico-clavate, 8-spored ascospores: hyaline, muriform, 3-7-septate transversely, 1-2-septate longitudinally, ellipsoid to subfusiform, 28-35 x 12-17 µm Pycnidia: not observed Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on bark in montane forests World distribution: warm tempearate parts of SW Europe, North and South America, and Australasia Sonoran distribution: Arizona, southern California and Chihuahua. Notes: Leptogium laceroides appears to be the isidiate counterpart of L. burgessii, that has secondary lobules and lacks the cylindrical/granular isidia found in L. laceroides.