The genus Thelonectria and closely related species with cylindrocarpon-like asexual states are a group of perithecial ascomycetes in the family Nectriaceae that occur as saprobes and in few cases as pathogens of hardw...The genus Thelonectria and closely related species with cylindrocarpon-like asexual states are a group of perithecial ascomycetes in the family Nectriaceae that occur as saprobes and in few cases as pathogens of hardwood trees,shrubs or other plants.Although a key component of forest ecosystems around the world,species relationships and distributions of these fungi are largely unknown.The objectives of this study were to:1)infer species rank phylogenetic relationships of the genus Thelonectria and closely related species with cylindrocarpon-like asexual states and test the monophyly of each of the groups studied;2)delimit taxa establishing taxon circumscriptions;3)resolve nomenclatural issues by identifying redundantly used names and synonyms;and 4)provide an updated outline to the genus,geographical distributions data and identification tools,specifically diagnostic keys and molecular data that can be used as molecular barcodes.The recovered consensus phylogeny resulted in a narrow circumscription of the genus Thelonectria,based on the type T.discophora,excluding one of the common species T.jungneri.According to the phylogenetic analyses,T.jungneri belongs in a segregate clade that should be recognized as a different genus.In the genus Thelonectria,a total of four new species and three new combinations are recognized.Additionally,three new genera,closely related to Thelonectria,are described to accommodate species displaying a morphological resemblance to those of Thelonectria:Cinnamomeonectria gen.nov.with C.cinnamomea as type species,Macronectria gen.nov.with M.jungneri as type species and including four additional newly described species,and Tumenectria gen.nov.with T.laetidisca as type species.展开更多
基金This study was funded by a grant from United States National Science Foundation(PEET program)DEB-0925696。
文摘The genus Thelonectria and closely related species with cylindrocarpon-like asexual states are a group of perithecial ascomycetes in the family Nectriaceae that occur as saprobes and in few cases as pathogens of hardwood trees,shrubs or other plants.Although a key component of forest ecosystems around the world,species relationships and distributions of these fungi are largely unknown.The objectives of this study were to:1)infer species rank phylogenetic relationships of the genus Thelonectria and closely related species with cylindrocarpon-like asexual states and test the monophyly of each of the groups studied;2)delimit taxa establishing taxon circumscriptions;3)resolve nomenclatural issues by identifying redundantly used names and synonyms;and 4)provide an updated outline to the genus,geographical distributions data and identification tools,specifically diagnostic keys and molecular data that can be used as molecular barcodes.The recovered consensus phylogeny resulted in a narrow circumscription of the genus Thelonectria,based on the type T.discophora,excluding one of the common species T.jungneri.According to the phylogenetic analyses,T.jungneri belongs in a segregate clade that should be recognized as a different genus.In the genus Thelonectria,a total of four new species and three new combinations are recognized.Additionally,three new genera,closely related to Thelonectria,are described to accommodate species displaying a morphological resemblance to those of Thelonectria:Cinnamomeonectria gen.nov.with C.cinnamomea as type species,Macronectria gen.nov.with M.jungneri as type species and including four additional newly described species,and Tumenectria gen.nov.with T.laetidisca as type species.