Taxonomy And Phylogeny Of Fomitiporella And Fulvifomes

Fomitiporella and Fulvifomes were established by Murrill within the Hymenochaetaceae in the early twentieth century,which can cause a white rot.As important pathogens of trees and decomposer in forest ecosystems,the taxonomy of Fomitiporella and Fulvifomes has important significance both in forest pathology and forest ecology.However,because of undefined taxonomic characteristics,their circumscriptions have been modified and re-delimited.Different opinions or disputes on taxonomy of these genera were existed among previous studies.Based on samples from all over the world,taxonomic and phylogenetic studies on Fomitiporella and Fulvifomes are carried out in the present study.In the morphology studies,the macro-and micro-morphological descriptions and drawings of 15 species in Fomitiporella and 24 species in Fulvifomes are provided,and identification keys for existed species in the two genera are proposed.The concepts of Fomitiporella and Fulvifomes are revised based on the current morphological study.Fomitiporella and Fulvifomes can be distinguished according to the presence or absence of pilei of basidiocarps.Fomitiporella is characterized by mostly resupinate and sometimes effused-reflexed basidiocarps with an indistinct subiculum(very thin to almost lacking).Fulvifomes resembles Fomitiporella,but has pileate basidiocarps.The macro-morphological characters of species in Fomitiporella and Fulvifomes are more or less homogeneous.In addition,species in each genus do not have host specificity,it is therefore difficult to distinguish the species within the genera.However,the hyphal structure,basidiospore shape and cystidioles are particularly important for species identification.Because of morphological similarity among species within Fomitiporella and Fulvifomes,it becomes confused in identification of similar species.However,phylogenetic analyses could provide DNA data for distinguishing them.Based on the internal transcribed spacer(ITS)regions and the nuclear large subunit(nLSU)regions,the phylogenetic trees are constructed with Maximum Parsimony(MP),Maximum Likelihood(ML)and Bayesian(BI)analyses.Phylogenetic studies show that Fomitiporella and Fulvifomes form two stable and independent lineages in Hymenochaetaceae.In addition,all species within Fomitiporella and Fulvifomes can be distinguished.In the present study,seven and eleven new species respectively in Fomitiporella and Fulvifomes are found:Fomitiporella americana,F.austroasiana,F.mangrovei,F.micropora,F.sinica,F.subinermis and F.vietnamensis,Fulvifomes australasicus,F.azonatus,F.caligoporus,F.centroamericanus,F.costaricense,F.floridanus,F.fundulicola,F.krugiodendri,F.nakasoneae,F.subindicus and F.submerrillii.In addition,these new species and their similar species are discussed.