Two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOF MS) was employed to analyze the volatile flavor compounds (VOCs) of Tricholoma matsutake samples from six different geographical regions: CX (Chuxiong), DL (Dali), DQ (Diqing), JL (Yanji), SC (Xiaojin) and XZ (Linzhi). The result indicate that a total of 2730 kinds of VOCs were identified from the fruiting bodies of six T. matsutake samples. The primary types of volatile organic compounds identified were 349 alcohols, 92 aldehydes, 146 carboxylic_acids, 311 esters, 742 organoheterocyclic compounds, 630 hydrocarbons, 381 ketones, 51 organic acids, and 28 derivatives and organosulfur compounds. Furthermore, PCA and PLS-DA analysis from the GC×GC-ToF-MS showed that samples from different regions could be distinguished by their VOCs. Network analysis revealed that 33 aroma compounds were identified as markers for distinguishing the samples from the six regions. The sensory attributes sweet, fruity, green, waxy, and floral were found to be more significant to the flavor profile of T. matsutake. 1-Nonanol, 2-Nonanone, Nonanoic acid, ethyl ester, 1-Undecanol, 2-Undecanone, Octanoic acid, ethyl ester, 2H-Pyran, and tetrahy-dro-4-methyl-2-(2-methyl-1-propenyl)- primarily contribute to the differences in the aroma characteristics among six T. matsutake samples. The results also provide a theoretical and practical foundation for the flavor compounds of these precious edible fungi in different regions.

Bolete specimens collected in Baima Snow Mountain Nature Reserve, Yunnan Province, were identified as Pseudobaorangia lakhanpalii, based on morphological and phylogenetic analyses. The ITS sequences of our collections exhibited a high similarity with Boletus lakhanpalii (99.53% for KEF13271 and 99.44% for KEF13272). However, because of limited molecular data and complex taxonomic relationships of Boletaceae, the phylogenetic placement of B. lakhanpalii could not be clearly determined. This study conducted a phylogenetic analysis by combining nrLSU, RPB2 and TEF1-α genes, and the results showed that this species has a close phylogenetic relationship with Baorangia, sharing some morphological characteristics, but also having several highlighting differences. Therefore, a new genus Pseudobaorangia is proposed with P. lakhanpalii as the type species and its detailed description is provided.

Stropharia daliensis sp. nov., collected from Dali, Yunnan, China, is proposed based on morphological and molecular analyses. It is characterized by its viscid to glutinous basidiomata, light reddish-brown to reddish-orange pileus covered with white to light yellow squamules, stipe evanescent annulus in the upper part of the stipe, below the annulus densely covered light yellow triangular squamules, acanthocytes absent. Phylogenetic analysis of the ITS and nrLSU confirmed the phylogenetic placement of the new species. A comprehensive description, line drawings of microstructures, and comparisons with morphologically similar species are provided in this paper.

The genus Aureonarius belongs to the family Cortinariaceae. In this study, phylogenetic inferences of Aureonarius were conducted based on sequences from a multi-locus dataset (ITS, nrLSU, RPB1, RPB2). A new species of Aureonarius discovered in Yunnan province of China was described based on morphological and molecular evidence. Aureonarius baimaensis is characterized by its medium-sized basidiomata; brownish-orange to reddish-brown tinge pileus and a pastel yellow tinge in the context; smooth central surface, with yellowish white to butter yellow finely fibrils near the edge; it typically has sterile lamella edges composed of smaller clavate cells. Morphological description, illustrations, and phylogenetic result of the new species are provided, as well as their comparisons to related taxa.

Callistosporium jianchuanense sp. nov., collected in Yunnan Province, Dali Bai Autonomous Prefecture, Jianchuan County, Laojunshan Mountain, is proposed based on phylogenetic analyses using ITS and nrLSU and morphological evidence. This new species is characterized by its small-sized basidiomata, an olive grey to olive green pileus covered with grey to black squamules, margins with partial veil remnants, non-striate, hygrophanous lamellae that turn black upon injury. A description, line drawings of microstructures, color images of basidiomata, and phylogenetic analysis results of the new species are provided, along with comparisons with similar species.