Towards a revised generic classification of lecanoroid lichens (Lecanoraceae, Ascomycota) based on molecular, morphological and chemical evidence

The phylogenetic relationship of lecanoroid lichens is studied using two data sets: 1) a 2-locus data set including 251 OTUs representing 150 species, and 2) a 6-locus data set with 82 OTUs representing 53 species. The genus Lecanora as currently circumscribed is shown to be highly polyphyletic and several genera, including Adelolecia, Arctopeltis, Bryonora, Carbonea, Frutidella, Lecidella, Miriquidica, Palicella, Protoparmeliopsis, Pyrrhospora, and Rhizoplaca are nested within Lecanora sensu lato. A core group of Lecanora is supported as monophyletic and includes species of the L. carpinea, L. rupicola, and L. subcarnea groups, and a core group of the L. subfusca group. Three monophyletic clades that are well supported in our analyses and well characterized by phenotypical characters are accepted here: 1) Myriolecis to accommodate the Lecanora dispersa group and Arctopeltis; 2) Protoparmeliopsis for the L. muralis group; and 3) Rhizoplaca is emended to include three placodioid taxa previously classified in Lecanora (L. novomexicana. L. opiniconensis, L. phaedrophthalma), whereas R. aspidophora and R. peltata are excluded from Rhizoplaca. The latter is transferred into Protoparmeliopsis. Lecidella is strongly supported as a monophyletic group. Our studies indicate the presence of additional clades of species currently placed in Lecanora sensu lato that warrant taxonomic recognition but additional data will be necessary before the circumscription of these entities is fully understood. 37 new combinations are proposed into the genera Myriolecis (30), Protoparmeliopsis (2), and Rhizoplaca (5).