Taxonomy And Molecular Phylogeny Of Crepidotus In China

Crepidotus (Fr.) Staude is the second largest genus of Inocybaceae after Inocybe, withmore than200species estimated worldwide, which is widely distributed and plays animportant role in forest ecosystems. some species have high edible value, for instance,Crepidotus mollis (Schaeff.) Staude, other species can pruduce anti-cancer bioactivesubstances, which have potential applications in the field of medicine. Due to the small size,lagre number of species, complicated interspecific relationship and the rich variation inspecies level, it is considered difficult to be identified by most taxonomist. The number ofrecored species of Crepidotus in China in approximately1/7th of that in the world, but thegenus is still poorly studied over China. Based on a thinking of polyphasic taxonomy, weattempt to make taxonimic and phylogenetic studied on Crepidotus in the present thesis, byusing a combined method of morphology and molecular phylogeny. The macrocharactersand ecological traits will be obtained based on a thinking of polyphasic taxonomy andintensive field survey, additional specimens deposited in other herbariums will be alsoexamined. Base morphological studies, the representative taxa and lower rank will beselected to reconstruct the molecular based phylogenetic tree, three loci, nLSU, rpb2andITS were used in the phylogenetic studies. Morphological data, ecological data andmolecular data will be analyzed comprehensively:1) infer the evolutionary relationshipsamong genus and lower rank;2) improve the infrageneric framework of Crepidotus andallied genera;3) delimit the infrageneric taxa(subgenus, section, subsection ect.);4) sortout species recogniton, especially the enigmatic species.（1）Taxonomy: Some235specimens, collected by the author and colleagues and186specimens from Herbaria were examined, Thirty-six taxa (including species and variety)were identified, among which includes6new species and12new records. The new speciesare: Crepidotus jilinensis T. Bau&S.S. Yang, C. hainanensis T. Bau&S.S. Yang, C.albidus T. Bau&S.S. Yang, C. sinuosu T. Bau&S.S. Yang, C. cortiola T. Bau&S.S. Yang,C. lutescens T. Bau&S.S. Yang. New records are: C. alabamensis Murril, C. calolepis var.squamulosus (Cout.) Senn-Irlet, C. cinnabarinus Peck, C. epibryus (Fr.) Quél, C.autochthonus J.E. Lange, C. cesatii (Rabenh.) Sacc, C. lundellii Pilá, C. subverrucisporusPilát, C. vulgaris Hesler&A.H. Sm, C. carpaticus Pilát, C. ehrendorferi Hauskn.&Krisai, C. sublatifolius Hesler&A.H. Sm. Re-examination of the voucher specimens of therecorded taxa were performed, and3taxa (C. cystidiosus Hesler&A. H. Sm. ect.)wereexcluded from the Chinese Crepidotus mycobiota or from their certain distribution area.7taxa (C. kauffmanii Hesler&A. H. Smith.ect.) without citation of any supporting materialsor do not share the same morphological characters as that described in the westernliterature, so made them temporary as uncertain species. The morphological descriptions,illustrations and the keys to species were provided.（2）Molecular phylogeny: Three loci, nLSU, rpb2and ITS were used in thephylogenetic studies,120new sequences were generated. The monophyly of Crepidotussensu lato was re-confirmed by the analysis of Crepidotus and allied genera based on nLSUsequences. Wood inhabiting genera, Simocybe and Pleuroflammula were sister group toCrepidotus. However, Hohenbuchelia, Pleurotus, Conchomyces and Cortinarius, whichwere considered to be more closely related with, nested far away in the phylogenetic tree.Mono-and multi-locus analysis were performed in the reconstruction of infragenericframework. Seven major clades were detected in all of the analysis except for the tef1-sequecnes analysis, because the lack of sequence data for certain clades. The three loci(nLSU, rpb2and ITS) have made good performance in the separation of the major clades,however, some contradicts also exsits in the topological structure. More higher postprobability value trees were obtained when combined data of the three loci were used.However, they works with difference in revealing the subclades of the major clades, therpb2sequence introduced by the present study could reveal the subclades of Crepidotusclade, Autochthonus clade, Dochmiopus clade and Sphaerula clade. the ITS sequenceintroduced by the present study could reveal the subclades of Crepidotus clade andDochmiopus clade. At least three phylogenetic species were exsited in the I. lanatodiscacomplex, the major clades in the phylogenetic tree correlated with geographic distributionto some extent.