Bambusicolous Fomitiporia revisited: multilocus phylogeny reveals a clade of host-exclusive species

is a genus of wood-inhabiting Hymenochaetaceae (Agaricomycetes) that includes pathogens and decomposers occurring on a wide array of plant substrates. Some species decay culms of woody bamboos, a poorly known biotic interaction. Four bambusicolous species of Fomitiporia are currently known. However, no studies concerning their phylogenetic relationships have been performed. In order to assess species boundaries and their relationships to each other, we conducted molecular phylogenetic analyses of nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and portions of nuc 28S rDNA (28S), RNA polymerase II second largest subunit (RPB2), and translation elongation factor 1-α (TEF1), as well as morphological analyses. Four species that occur on culms of woody bamboos, F. bambusarum, F. spinescens, F. uncinata, and the new species F. bambusipileata, grouped together in an exclusive clade within a primarily Neotropical lineage. The new species differs from all other species in the group by the pileate basidiomata. Hypotheses regarding host-exclusivity are discussed.