A multi‑gene phylogeny clarifies species diversity, taxonomy, and divergence times of Ceriporia and other related genera in Irpicaceae (Polyporales, Basidiomycota)
Wang Cg
Abstract
Phylogenetic and morphological analyses on Ceriporia and other related genera in Irpicaceae were carried out.Ceriporia, Gloeoporus, and Meruliopsis characterised as resupinate, effusedreflexed or pileate polypores with poroid and smooth hymenophore, a monomitic hyphal structure, crystals, and an oily substance are contained in the Irpicaceae.Ceriporia and Meruliopsis are phylogenetically related as sister genera.They share resupinate to rarely effused-reflexed basidiomata with a white, buff to brightly colored hymenophore, a monomitic hyphal structure with simple septa on the generative hyphae, and ellipsoid, cylindrical to allantoid basidiospores.However, hymenial cystidia are present in most Meruliopsis species, while they are absent in most Ceriporia species.Gloeoporus is distinguished from Ceriporia and Meruliopsis by having a gelatinous hymenophore and generative hyphae, sometimes with clamp connections.Phylogenies on Ceriporia and other related genera were reconstructed using multiple loci DNA sequences, including the internal transcribed spacer regions (ITS), the large subunit of nuclear ribosomal RNA gene (nLSU), the largest subunit of RNA polymerase II (RPB1), the translation elongation factor 1α gene (TEF1) and the small subunit of nuclear ribosomal RNA gene (nSSU), as well as two combined datasets (ITS+nLSU) and (ITS+nLSU+RPB1+TEF1+nSSU). Eleven new species in Ceriporia are described and illustrated, four new combinations in the genus are proposed.Two new species in Gloeoporus and three in Meruliopsis are described and illustrated.Moreover, the evolutionary times of Ceriporia and other related genera in Irpicaceae were revealed based on conserved regions of five DNA fragments (ITS+nLSU+RPB1+TEF1+nSSU). Bayesian evolutionary analysis shows the divergence time of Irpicaceae emerged with a mean stem age of 169.1 Mya [95 % highest posterior density (HPD) of 124.66-231.04Mya], which occurred during the middle Jurassic.Ceriporia and Meruliopsis grouped and the initial diversification occurred during the early of the Cretaceous with a mean stem age of 113.99 Mya [95% highest posterior density (HPD) of 81.53-153.07Mya].Gloeoporus emerged earlier with a mean stem age of 142.84 Mya [95% highest posterior density (HPD) of 102.39-196.41Mya], which occurred during the early Cretaceous.