New species and new records of Meliolaceae from Panama

Three new species of Meliolaceae, Appendiculella monsterae on Monstera deliciosa (Araceae), Asteridiella nitidae on Buddleja nitida (Scrophulariaceae), and Irenopsis chrysophylli on Chrysophyllum sp. (Sapotaceae), are described based on material collected in Panama. Eighteen species of Meliolaceae are reported for the first time for Panama, which include four first records for the Americas, viz. Ast. formosensis, Meliola indica, and M. pisoniae, previously known only from Asia, and M. dissotidis hitherto known only from Africa. Six species of plants are cited as hosts for meliolaceous fungi for the first time. In a phylogenetic hypothesis based on 28S nrDNA sequences, the position of Meliolales, including Appendiculella, Asteridiella, Endomeliola, Irenopsis, and Meliola, is found to be basal to Sordariomycetidae, Hypocreomycetidae, and Xylariomycetidae within Sordariomycetes. The five genera of Meliolaceae form a strongly supported clade. We suggest adopting the concept of the subclass Meliolomycetidae. The monophyly of Asteridiella cannot be confirmed. A hypothetical close relationship between Asteridiella and Appendiculella is not supported, but Endomeliola appears closely related to a species of Asteridiella. Two Meliola species on the same host family are closely related.