| Partial species of Mycena(Pers.)Roussel can form mycorrhiza with a variety of plants such as Gastrodia R.Br.,which have important significance to ecological and economic research.Mycena contains more than 600 species within 44 sections,and it is generally considered to be a difficult group in taxonomy of fungi due to the unclear phylogenetic relationship,disputes over framework and species division within the genus.The members of Mycena sect.Calodontes(Fr.Ex Berk.)Quél.,were well characterized by the purplish basidiomata and smooth cystidia,pileipellis,and stipitipellis,are the key groups in the morphological and phylogenetic framework of Mycena.A total of 20 species have been reported all over the world,mostly distributed in the north temperate zone and are saprophytic,some species are edible and medicinal,a few containing trace alkaloids can cause poisoning,and some found in subtropical or tropical area have biofluorescence.M.sect.Calodontes exhibits essential scientific research and economic value in the fields of Mycena systematic evolution,toxin research and so on,but many taxonomic questions that need to be solved: the circumscription of M.pura complex is ambiguous,few sequences are available,the phylogenetic framework is not clear,and the species diversity is seriously underestimated due to the severe shortage materials from China.Based on the above questions,we intend to conduct the taxonomic and phylogenetic studies of M.sect.Calodontes using ecological observation,morphological anatomy and phylogenetic analysis under a large number of collected and deposited specimens.In this study,three unlinked gene loci,namely the internal transcribed spacer(ITS),RNA polymerase II largest subunit(rpb1),and translation elongation factor-1 alpha(tef1-α),were used for phylogenetic analysis.Phylogenetic species were recognized based on the Genealogical Concordance Phylogenetic Species Recognition(GCPSR),and the morphological and anatomical results were combined to reveal the circumscription of M.pura complex,the species diversity,and phylogenetic relationship.Based on the polyphasic taxonomic study of 165 specimens collected by the author and 6 specimens from Italy,the results are summarized as follows:1 Circumscription and concepts in M.pura complexThe basidiomata color range in M.pura complex is so wide that it is difficult to distinguish accurately from other species by macromorphology.In this study,M.pura complex was confirmed to be polyphyletic in the basis of anatomy and polygenetic phylogeny analysis.The phylogenetic species in this complex are highly similar in microscopic morphology,there are some differences in color,size,and attachment of lamellae,but it is hard to form obvious and stable distinguishing characteristics.Based on the current phylogenetic results,8 new phylogenetic species of M.pura complex were revealed.In addition,the morphological comparison with other species in sect.Calodontes showed that the shape of cheilocystidia and pleurocystidia and the existence of pleurocystidia were critical characters to define the range of M.pura complex.The cheilo-and pleurocystidia of members in M.pura complex all were clavate,fusiform to utriform,and base contracted,while other species in sect.Calodontes had obvious differences in the shape of cystidia and the existence of pleurocystidia.2 Species diversity of sect.Calodontes in ChinaThe fieldwork of this study covered the whole latitudes of China,and a total of 165 specimens were collected.By morphological and phylogenetic analysis,11 new species in sect.Calodontes and 8 new phylogenetic species within M.pura complex were identified.Detailed morphological descriptions,discussion,habitat photographs,drawings,and microstructural photographs of each taxon were provided.There were 5new species had been published,M.polycystidiata Z.W.Liu,Y.P.Ge,L.Zou & Q.Na,M.rufobrunnea Z.W.Liu,Y.P.Ge & Q.Na,M.shengshanensis Z.W.Liu,Y.P.Ge & Q.Na,M.subulata Z.W.Liu,Y.P.Ge & Q.Na,and M.yuezhuoi Z.W.Liu,Y.P.Ge & Q.Na.According to the collection of specimens,the members of sect.Calodontes widely distributed from the cold temperate to the temperate zone,and gradually decreased from the warm temperate to the subtropical zone.Regarding habitat,the specimens were mostly found in coniferous or mixed coniferous-broadleaved forests.3 Phylogenetic relationship in sect.CalodontesITS+rpb1+tef1-α combined analysis was used for the first time to establish a framework within sect.Calodontes,the phylogenetic analysis failed to fully support the division of subsections based on morphology.The species within subsect.Marginatae had colored lamellae edge and amyloid spores,which are the most easily identified among the three subsections at present.However,only one specimen belonging this subsection was collected,which was described as new species.The members of subsect.Violacellae shared inamyloid basidiospores and absent pleurocystidia.M.pearsoniana in this subsection formed a highly supported clade with M.shengshanensis,M.subulata,and two new species,but basidiospores of other species were amyloid despite lack of pleurocystidia except M.pearsoniana.Subsect.Purae contained most species of sect.Calodontes,which had amyloid spores and colorless cheilo-and pleurocystidia.However,the mentioned above pleurocystidia absent and spores amyloid species also do not meet the division criteria of this subsection.At the same time,subsect.Purae was supported to be polyphyletic in this study,and the existing framework of sect.Calodontes has the limitation.This study carried out a systematic work on sect.Calodontes based on extensive collection and borrowing of specimens by morphological and phylogenetic analysis.A total of 11 new species and 8 new phylogenetic species of M.pura complex were identified,the circumscription of this complex was clarified,and the species diversity of sect.Calodontes was enriched,which provided the underlying data for the phylogenetic framework of this section,as well as theoretical basis for the development of edible fungi. |
