Taxonomy And Phylogeny Of Hydnoid Fungi In Hericiaceae In China

Hericiaceae is a family of fungi belonging to Russulales,and currently comprises four hydnoid-fungi genera:Dentipellicula,Dentipellis,Dentipellopsis,Hericium;a corticioid-fungi genus:Laxitextum;two poroid-fungi genera:Pseudowrightoporia and Wrightoporiopsis.Taxa in the family are saprobic on rotten wood causing white rot.In this study,four hydnoid-fungi genera:Dentipelliculay Dentipellis,Dentipellopsis and Hericium,were identified regarding on the information of morphological features,substarate preferences,geographical distribution and phylogenetic analyses of DNA sequences.Most of the materials were kept in the herbarium of BJFC and IFP,and a small number of them were borrowed from DAOM.DNA sequences were used to constructe the phylogenetic trees by Maximum Parsimony,Maximum Likelihood and Bayesian methods.The study shows that there are two species of Dentipellicula(D.leptodon and D.taiwaniana)and six species of Dentipellis(D.coniferarum,D.fragilis,D.longiuscula,D.microspora,D.rhizomorpha and D.tropicalis)including two new,D.longiuscula and D.tropicalis;one species of Dentipellopsis(D.dacrydicola);four species of Hericium(H.abietis,H.coralloides,H.erinaceus,H.yumthangense),and H.yumthangense is a new Chinese record.Identification key for Hericiaceae is proposed.Detailed descriptions and microscopic structure drawings of all species belonging to four hydnoid-fungi genera are provided.The main bases for intergeneric classification are:the shape of basidiocarps;generative hyphae is cyanophilous or not;the thin or thick walls of basidiospores.The main bases for species level are:the shape of basidiocarps;branching types;the length and density of spines;the sterile structures,such as gloeocystidia,dendrohyphidia and cystidia,present or not;generative hyphae present or not;the size of basidiospores.Phylogenetic analysis based on ITS and nLSU sequences indicated that Hericiaceae divided into two major lineages.One lineage was composed of Dentipellis,Hericium and Laxitextum,while Dentipellicula,Dentipellopsis,Pseudowrightoporia and Wrightoporiopsis belonged to another,Dentipellis was polyphyletic,species in this genus separated into three clades:the core clade(represented by D.fragilis,D.longiuscula,D.ohiensis,D.rhizomorpha,D.tropicalis),D.coniferarum clade and D.microspora clade.