First checklist of lichens and lichenicolous fungi from Mauritius, with phylogenetic analyses and description of new taxa

A first checklist of the lichens and lichenicolous fungi from the Republic of Mauritius is presented. It is based on older literature reports and on collections made by the authors, mainly in 2016, from the isles of Mauritius and Rodrigues. A total of 216 species are accepted, either as relevant specimens have recently been critically studied or revised by lichen taxonomists, or as we have collected and identified such material ourselves. A further 226 taxa have been reported from Mauritius but are not accepted here, either as no relevant herbarium material has recently been examined, or as previous records are dubious or erroneous; 111 taxa have been newly described from Mauritius in the past, plus 12 of which the Mauritian origin is dubious. Here we report 56 taxa as new for the island of Mauritius, and we describe two new genera (Baidera, Serusiauxia) and eight new species (Baidera mauritiana, Biatoropsis millanesiana, Chapsa alletii, Collemopsidium mauritiae, Nyungwea pyneei, Porina florensii, Pyrenula muriciliata, Serusiauxia inexpectata). Two new combinations are proposed: Loekoesia apostatica (≡ Lecanora apostatica) and Sticta flavireagens (≡ Stictina flavireagens). Phylogenetic analyses are presented for species of Arthoniales, Biatoropsis, Porinaceae, Pyrenulaceae and Teloschistales.