A taxonomic revision of the lichen genus Lecanoropsis (Lecanoraceae)

Lecanora s. lat. is a genus of crustose lichens comprising c. 1000 recognized species and subdivided into several morphology-based groups. One of the groups that has rarely been studied by molecular methods is the L. saligna-group. This group includes corticolous and lignicolous species of Lecanora, usually containing isousnic or usnic acid (or both) as major secondary metabolites. We present here a systematic revision of 23 species belonging to the L. saligna-group with descriptions and an identification key. A phylogenetic analysis based on seven loci is also included in this work, comprising the majority of the recognized species ascribed to the L. saligna-group. Four new primer pairs for mitochondrial loci were designed and resulting sequences were included in the phylogenetic dataset. Previous phylogenetic analyses of the Lecanora Saligna-group had shown the monophyletic status of a “core” saligna-clade with two species formerly recognized as belonging to the L. saligna-group appearing as sister to this clade, with no phylogenetic support. The analysis including four more mitochondrial loci and one more nuclear locus, provides well-supported delimitation of the species within the L. saligna-group and confirms the monophyly of the “core” saligna-clade. We therefore propose the segregation of the species within this clade into the genus Lecanoropsis M. Choisy ex Ivanovich. Six species are described as new to science: Lecanoropsis austrocascadensis Hollinger & Ivanovich, L. coracina Ivanovich, Otte & Sheehy, L. iapyx Ivanovich & Hollinger, L. micans Ivanovich, Hollinger & Printzen, L. omissa Palice, Ivanovich & Printzen and L. prolificans Ivanovich, Hollinger & Printzen.