Within Agaricus subg. Minores, A. sect. Minores remains a little-studied section due generally to its delicate sporocarps often lacking taxonomically relevant morphological characters. To reconstruct the section, using the recent taxonomic system based on divergence times, and to evaluate the species diversity of A. sect. Minores in the Greater Mekong Subregion, 165 specimens were incorporated in phylogenetic analyses. A dated tree based on nuclear ITS, LSU and tef1-α sequence data allowed us to better circumscribe A. subg. Minores and to propose a new subgenus, A. subg. Minoriopsis, which is only known from tropical and subtropical regions of the Americas. A larger tree based on ITS sequences indicated that, with 81 phylogenetic species, the reconstructed section Minores is now one of the largest sections in the genus. Within A. subg. Minores, a new section, A. sect. Leucocarpi, and eleven new species are described from the Greater Mekong Subregion. Thirty-eight species of A. sect. Minores from this region of Asia were distributed in multiple clades that successively diverged over the past 24 million years. In contrast, species reported from Europe mostly grouped in a single non-tropical clade, suggesting a major species diversification following the middle Miocene climatic optimum.

The genus Agaricus is known for its medicinal and edible species but also includes toxic species that belong to section Xanthodermatei. Previous phylogenetic reconstruction for temperate species, based on sequence data of nuc rRNA gene (rDNA) internal transcribed spacers (ITS), has revealed two major groups in this section and a possible third lineage for A. pseudopratensis. Recent research in Agaricus has shown that classifications need improving with the addition of tropical taxa. In this study we add new tropical collections to section Xanthodermatei. We describe three species from collections made in Pakistan and Thailand and include them in a larger analysis using all available ITS data for section Xanthodermatei. Agaricus bisporiticus sp. nov. and A. fuscopunctatus sp. nov. are introduced based on molecular and morphological studies, whereas A. microvolvatulus is recorded for the first time in Asia. Specimens from Thailand however have a much larger pileus than the type specimens from Congo. In maximum likelihood (ML) and maximum parsimony (MP) phylogenetic analyses these three species cluster with A. pseudopratensis from the Mediterranean area and A. murinocephalus recently described from Thailand. In Agaricus section Xanthodermatei this new group is monophyletic and receives low bootstrap support whereas the two previously known groups receive strong support. Within the new group, the most closely related species share some traits, but we did not find any unifying morphological character; however the five species of the group share a unique short nucleotide sequence. Two putatively toxic species of section Xanthodermatei are now recognized in Pakistan and six in Thailand.

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http://www.diva-portal.org This is the published version of a paper published in Fungal diversity.

Micropsalliota embraces approximately 70 species which are mainly distributed in tropical and subtropical areas. In this study, two new species named Micropsalliota albella and M. purpureobrunneola are introduced from northern Thailand. Phylogenetic analyses based on ITS and LSU data shows their placement in Micropsalliota in two distinct lineages. Micropsalliota albella is characterized by the white, tiny basidiomes and utriform cheilocystidia. Micropsalliota purpureobrunneola is characterized by the pileus finely covered with purple to brownish-purple scales, oblong basidiospores and narrowly clavate cheilocystidia. Descriptions, colour photographs and illustrations of both new species are presented.

A chemical investigation on the fruiting bodies of Fomitopsis pinicola led to the isolation and identification of 28 lanostane triterpenoids including 11 new compounds (1−11) and 17 known analogues (12−28). Their structures were elucidated by extensive one-dimensional NMR, two-dimensional NMR, and MS spectra. All isolates were tested for their anti-inflammatory activity, protein tyrosine phosphatase 1B (PTP1B) inhibitory activity in vitro, and effect on glucose uptake in insulin-resistant HepG2 cells. Compounds 1, 4, 22, 23, and 27 inhibited the nitric oxide released from the LPS-induced RAW 264.7 cell assay with IC 50 values in the range of 21.4−27.2 μM. Compounds 18, 22, 23, and 28 showed strong PTP1B inhibitory activity with IC 50 values in the range of 20.5−29.9 μM, comparable to that of the positive control of oleanolic acid (15.0 μM). Compounds 18 and 22 were confirmed to be good competitive inhibitors of PTP1B by kinetic analysis. In addition, compounds 18, 22, and 28 were found to stimulate glucose uptake in the insulin-resistant HepG2 cells in the dose from 6.25 to 100 μM. These findings indicated the potential of F. pinicola in the development of functional food or medicine for the prevention and treatment of diabetes.

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Species diversity of Micropsalliota in China remains poorly known, especially in southwestern China, a hotspot of biodiversity. Based on morphological characteristics and molecular phylogenetic analyses using ITS and nrLSU sequences, three new species named Micropsalliota delicatula, M. dentatomarginata and M. digitatocystis are introduced from China. Phylogenetc analyses results indicated the unique phylogenetic positions of three new species in Micropsalliota. Full descriptions, photo plates, illustrations and a phylogenetic tree to show the placement of three new species are presented.