| Hymenogastraceae Vittad.is a worldwide widely distributed group of Agaricales,with important ecological and economic values.Traditionally,the Hymenogastraceae fungi are underground mycorrhizal fungi with nearly hemispheric basidiomata.However,with the application of molecular biology techniques in taxonomy,some agaricoid fungi have been classified into this family.Since 2012,our team had been paying attention to the study of this group,and carried out systematic taxonomic studies on several important agaricoid fungi of this family.In this paper,the phylogenetic relationships and interspecies relationships among the five genera were investigated by taking the genera Hymenogaster,Galerina,Phaeocollybia,Alnicola,Hebeloma and their related genera as the main research objects.For taxonomic studies,morphological observation of 336 specimens collected from 20 provinces(autonomous regions)in China and more than 300 specimens deposited in the Herbarium of Mycology of Jilin Agricultural University(HMJAU)were studied.102 specimens from other domestic herbarium were also examined.5genera of Hymenogastraceae were described.44 taxa including 1 species which belong to Hymenogaster,13 species which belong to Galerina,1 species which belong to Phaeocollybia,7 species which belong to Alnicola,and 22 species which belong to Hebeloma were described.Among them G.variibasidia T.Bau & X.L.Liu,Ph.guangxiensis T.Bau & X.L.Liu,H.subdunense T.Bau & X.L.Liu and H.cremeoalbum T.Bau & X.L.Liu are 4 new species.G.jaapii A.H.Sm.& Singer,G.physospora Singer,G.badipes(Pers.)K(?)hner,G.tibiicystis(G.F.Atk.)K(?)hner,G.sahleri(Quél.)K(?)hner,G.pseudomniophila K(?)hner,A.silvaenovae(D.A.Reid)Courtec.,A.badiofusca P.-A.Moreau,A.citrinella P.-A.Moreau & A.de Haan,H.parvisporum Sparre Pedersen,L(?)ss(?)e,Beker & U.Eberh,H.victoriense A.A.Holland & Pegler,H.youngii B.J.Rees,H.lactariolens(Clémen(?)on & Hongo)B.J.Rees & Orlovich,H.excedens(Peck)Sacc.,H.alpinicola A.H.Sm.,V.S.Evenson &Mitche,H.clavulipes Romagn.,H.grandisporum Beker,U.Eberh.& A.Ronikier,H.vaccinum Romagn.,H.louiseae Beker,Vesterh.& U.Eberh.,H.geminatum Beker,Vesterh.& U.Eberh.,H.fragilipes Romagn.,H.quercetorum Quadr.,H.subconcolor Bruchet,H.birrus(Fr.)Gillet [as ’birrum’],H.nanum Velen.,H.parvicystidiatum Beker,Vesterh.& U.Eberh.,H.theobrominum Quadr.are 28 species first recorded in China.Detailed morphological description,field habitat photographs and microstructural line diagrams were provided for each new species and newly recorded species.Supplementary descriptions and line drawings for some specimens examined in the herbarium were provided.Keys of species to Galerina,Alnicola and Hebeloma were compiled.Excluded the distribution of two incorrectly identified species in China,and two other species need further research due to lost of specimens.More than 300 new sequences were generated,and 150 self-tested sequences were selected for phylogenetic tree construction.Three phylogenetic trees constructed based on ITS sequence were used to study the subclassification and interspecific relationship of Galerina,Phaeocollybia,Alnicola and Hebeloma.It is confirmed that the genus Galerina can be divided into 5 subgenera,which supports the establishment of the subgenus Sideroides.And the genus Alnicola can be divided into 2 subgenera and the genus Hebeloma into 7 sections.Morphological identification of new species and new recordes was verified in both phylogenetic trees.In the phylogenetic tree which constructed by the combination sequences of ITS,LSU and rpb2,all the sequences were clustered into two large clade,Hymenogastraceae and Strophariaceae,which were in a parallel relationship.The Hymenogastraceae clade contained six stable clades: Phaeocollybia,Psilocybe,Flammula,Alnicola,Hymenogaster and Hebeloma.Species of Galerina divided into 3 clades.And the Gymnopilus clade clustered with Galerina-2 Clade.The Strophariaceae clade was divided into four distinct branches: Pholiota,Stropharia,Agrocybe and Deconica.In addition,the three symbiotic mycorrhizal genera in Hymenogastraceae clustered into one clade,and the saprophytic fungi clustered into another clade with the genus Phaeocollybia.Ecological habits and nutritional patterns are important basis for the study of the relationship between the genera of Hymenogastraceae.The phylogenetic tree constructed with multiple genes supports the classification of the subgenera for Galerina,Alnicola and Hebeloma. |
