The following taxa are newly reported from Pennsylvania: Absconditella sphagnorum, Cladonia cariosa, C. submitis, Coenogonium luteum, Dactylospora glaucomarioides (on Ochrolechia yasudae), Flakea papillata, Heterodermia squamulosa, Lecanora epanora, Lecidea nylanderi, Lichenochora galligena (on Physcia americana), Lithothelium septemseptatum, Megalospora porphyritis Opegrapha zonata, and Sarea difformis. A second population of Opegrapha bicolor, otherwise known only from the type locality in Monroe County and a disjunct population in Uganda, is reported. A modern collection of Pertusaria trachythallina is reported. Many of the species discussed are restricted to remnant high quality, undisturbed habitats in the study area.