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Peltula michoacanensis (B. de Lesd.) Wetmore
Family: Peltulaceae
Peltula michoacanensis image
Thallus: squamulose, widely scattered squamules: concave and cone shaped, 1-2 mm in diam., shallowly or deeply lobed; margins: ascending upper surface: tan-olive, not sorediate upper cortex: not developed but with a yellowish epinecral layer (up to 12 µm thick) medulla: composed of loosely to densely interwoven hyphae of elongated cells; algal layer: indistinctly delimited above lower cortex: 25-50 µm thick, 3-5 layers of globose hyphal cells lower surface: paler than the upper surface, attached by a central branched umbilicus Apothecia: one per squamule, immersed in the center of concave squamules; disc: light brown, according to Wetmore (1970), 0.5-1 mm in diam.; epihymenium: light brown, K-; hymenium: I+ wine-red (probably due to the reaction of ascus walls), 150-220 µm high, >100-spored ascospores: ellipsoid to bacilliform, 6.1-7.7 x 3.4-4.6 µm Pycnidia: immersed, chambered conidia: fusiform, 3.1-3.7 x 1.2-1.8 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on soil over acidic or calcareous rocks in deserts and other open, arid habitats World distribution: SW North America to central Mexico and India Sonoran distribution: desert areas of southern California.