The phylogeny of selected Phylloporus species, inferred from NUC-LSU and ITS sequences, and descriptions of new species from the Old World

Abstract

The phylogeny of Phylloporus (Boletaceae) has not been well studied, and the taxonomic relationships of this genus have varied considerably among authors. The following study presents phylogenetic relationships of Phylloporus based on two nuclear ribosomal DNA regions, ITS and LSU. The ITS dataset includes 39 collections and the LSU dataset contains 50 collections of Phylloporus. A combined analysis of both genes did not resolve the deeper nodes in the phylogeny, but the results suggest that Phylloporus is monophyletic and a sister group of the Xerocomus subtomentosus group. The lamellate hymenophore configuration is a synapomorphy that distinguishes Phylloporus from the other genera in the family. The placement of a lamellate genus within Boletaceae suggests that hymenophore evolution is not well understood in the family. This is the first phylogeny of Phylloporus and includes 20 species from different geographic regions. Six taxa of Phylloporus from the Old World are here presented. Phylloporus cyanescens is a new combination for an Australasian taxon formerly named as a variety of P. bellus (Massee) Corner. Phylloporus pumilus is described from Indonesia, and 4 species are described from Thailand: P. castanopsidis, P. dimorphus, P. infuscatus, and P. rubiginosus.