Taxonomic Revision of the Lichen Genera <i>Pertusaria</i>, <i>Varicellaria</i>, and <i>Variolaria</i> (Pertusariales, Ascomycota) in South Korea.

The crustose lichen genus Pertusaria comprises over ca. 800 species worldwide. In total, 20 Pertusaria species were localized to the Mt. Sorak and Jeju-do in Korea. To date, information regarding the distribution of Pertusaria species in the South Korean peninsula is scarce. In this study, we collected Pertusaria species across South Korea and identified them based on morphological, chemical, and molecular characteristics. Of the 387 samples collected, we identified 24 taxa and 1 variety, of which 17 were previously recorded, and 6 taxa were newly found in South Korea (P. leioplaca, P. leucosora var. violascens, P. texana, P. thiospoda, P. thwaitesii, and P. xanthodes), 2 known species were transferred to Varicellaria (Varicellaria lactea and V. velata), one species was transferred to Variolaria as a new record (Variolaria multipunctoides) and one was a new species (P. jogyeensis J. S. Park & J.-S. Hur, sp. nov.). Characteristics of the newly discovered species, P. jogyeensis, are as follows: smooth to bumpy thallus, scattered to crowded poriform apothecia, blackish ostioles, definitely sunken, thin yellowish green rims around ostioles, 8-spored ascus, and the presence of perlatolic acid and thiophaninic acid (chlorinated xanthone). Phylogenetic studies on P. jogyeensis based on the mitochondrial small subunit sequence revealed proximity to P. flavicans and P. texana, and supported its classification as a new species within the genus Pertusaria. Additionally, we describe the chemical composition and morphology of all listed species in detail and provide an artificial key for identification.