Molecular phylogeny of eastern Asian species of Amanita (Agaricales, Basidiomycota): taxonomic and biogeographic implications

The phylogenetic relationships, taxonomy and biogeography of the genus Amanita with emphasis on eastern Asian species were estimated using sequence data from both internal transcribed spacer (ITS) regions and large subunit (nLSU) of nuclear ribosomal DNA. The separation of the two traditionally accepted subgenera was not well supported. Each section of Amanita, Vaginatae, Caesareae, Phalloideae, Validae and Amidella was supported as monophyletic by different methods of analysis and data sets of different regions. The monophyly of section Lepidella remained unclear. A few biogeographic and taxonomic implications were inferred: (1) few species of Amanita are widely distributed throughout eastern Asia, Europe and North America. Samples of some previously recognized disjunct species in the Northern Hemisphere were not monophyletic. Thus, the putative intercontinental disjunct distributions of these species were not supported in this study; (2) biogeographic relationships between Amanita of eastern Asia and Europe are relatively close and several taxa are common to both regions, while paired or closely related species between eastern Asia and North America are relatively common, but rarely have been confirmed as disjunct populations of the same species by molecular data yet. A number of species of Amanita in North America labelled with names based on European materials should be regarded as distinct species; (3) a few genetically cryptic species of Amanita in southwestern China need to be delimited; and (4) variations in colour and morphology of the fruit bodies in A. parvipantherina from different localities should be interpreted as modifications of environment.