Proposal of one new family, seven new genera and seventy new basidiomycetous yeast species mostly isolated from Tibet and Yunnan provinces, China

Functional adaptation of PM2.5 microbiomes to varying environmental conditions in Northeast Asia: Ulaanbaatar, Seoul, and Noto

This study examined the bacterial and fungal communities associated with PM2.5 collected from three geographically distinct locations in Northeast Asia-Ulaanbaatar (high pollution), Seoul (moderate pollution), and Noto (low pollution)-which collectively represent a gradient of urbanization and environmental conditions during the spring sampling period from March 15 to April 7, 2022. Ulaanbaatar exhibited the highest abundance of both bacteria and fungi, yet exhibited the lowest fungal diversity. In contrast, Noto exhibited the lowest microbial abundance but the highest fungal diversity, while Seoul displayed intermediate values. Dominant bacterial genera, including Caldalkalibacillus, Halomonas, and Nesterenkonia, demonstrated notable resilience across all three locations, highlighting their adaptability to diverse environmental conditions. The dominant fungal genera were Cladosporium and Candida. Analyses revealed significant correlations between microbial community structures and environmental factors. In Ulaanbaatar, microbial communities were strongly associated with meteorological parameters such as temperature, humidity, and wind speed. In Seoul, stronger correlations were observed with polycyclic aromatic hydrocarbons (PAHs). Noto exhibited weaker correlations with both meteorological factors and organic compounds. Across all sites, bacteria consistently showed broader niche breadths compared to fungi, reflecting their greater metabolic versatility and resource utilization capacity. Both bacterial and fungal niche breadths generally increased at intermediate concentrations of alkanes and DCAs but declined at extreme concentrations, suggesting optimal survival ranges. These findings highlight the complex interplay of environmental factors and pollutants in shaping microbial community structures and functional diversity across diverse geographical settings during the spring season.

Five new epiphytic species of Vishniacozyma (Bulleribasidiaceae, Tremellales) from China

The genus Vishniacozyma, globally distributed, encompasses numerous epiphytic and endophytic species. In this study, five new species are proposed to accommodate eleven yeast strains isolated from leaves of different plants: V.diospyri sp. nov. (holotype CICC 33574T), V.guiyangensis sp. nov. (holotype CICC 33569T), V.pingtangensis sp. nov. (holotype CICC 33596T), V.eriobotryae sp. nov. (holotype GDMCC 2.312T), and V.tianchiensis sp. nov. (holotype CICC 33617T) using phenotypic and phylogenetic characters. Phylogenetic analysis was based on the internal transcribed spacer (ITS) region and the D1/D2 domain of the large subunit (LSU) rRNA gene. Illustrations and descriptions of these five taxa are provided, along with comparative analyses with closely related species within the genus. This research highlights the considerable diversity of Vishniacozyma species in China and contributes valuable data for future investigations in fungal systematics and evolution.

Two new arthroconidial yeast species from bark and pit mud in China

A study on yeast species from the genera Geotrichum and Magnusiomyces in southwest and central China was conducted based on morphological and molecular phylogenetic analyses using the ITS region and the D1/D2 domain of the LSU rRNA gene. The research identified two new yeast species: Geotrichumhubeiense and Magnusiomycespitmudophilus. The study contributed to understanding arthroconidial yeast diversity in fermentation and natural environments and paved the way for future taxonomic and ecological studies. Descriptions, illustrations, and phylogenetic analysis results of the two new taxa are provided.

Peltigera lichens as sources of uncharacterized cultured basidiomycete yeasts

Lichens represent one of the most successful examples of symbiosis. They are constituted by the association between a dominant fungus (i.e., the mycobiont), one or more photosynthetic partners (algae or cyanobacteria), and harbor an array of associated microorganisms, including bacteria and fungi. The associated fungal communities in lichens, known as the "lichen mycobiome", are composed of both ascomycetes and basidiomycetes, including filamentous and yeast taxa. Recently, basidiomycete yeasts have received considerable attention as a much-overlooked source of diversity within the lichen mycobiome, with hypothesized roles in lichen symbiosis. This study surveyed the diversity of cultivable basidiomycete yeasts associated with Peltigera lichens across southern Chile. A phylogenetic study based on sequences of 179 yeast isolates allowed the identification of 29 taxa from 13 genera in the classes Agaricostilbomycetes, Cystobasidiomycetes, Microbotryomycetes, and Tremellomycetes, with the latter being the most represented. This research revealed several yeast species, including members of the genera Boekhoutia and Goffeauzyma, in lichens for the first time, thereby expanding our understanding of lichen-associated fungal diversity. In addition, four new cultivable species isolated from Peltigera are formally described. These are Boekhoutia peltigerae sp. nov., Cystobasidium chilense sp. nov., Genolevuria patagonica sp. nov. and Pseudotremella navarinensis sp. nov. These results highlight the role of lichens as reservoirs of uncharacterized basidiomycete yeasts.

Meira qingyuanensis sp. nov., an anamorphic yeast species isolated from plant leaves

Two yeast strains, NYNU 224191 and NYNU 22411, were isolated from plant leaves of Cyclobalanopsis jenseniana and Schisandra sp. harvested from Qingyuan Mountain, Quanzhou City, Fujian Province, southeast China. Molecular phylogenetic analyses demonstrated that these two strains represent a novel species in the genus Meira. They are more closely related to M. marina, M. nashicola, M. plantarum and M. pileae than other Meira species based on phylogenetic analysis of the internal transcribed spacer (ITS) region and the D1/D2 domain of the large subunit (LSU) rRNA gene. The novel species differed from its closest relatives, M. marina, M. nashicola, M. plantarum and M. pileae, by 1.8-2% sequence divergence (11-12 substitutions and 1-2 gaps) in the D1/D2 domain and over 6.7% sequence divergence (40-60 substitutions and 53-77 gaps) in the ITS region, respectively. We propose the name Meira qingyuanensis sp. nov. (Holotype CICC 33567; Mycobank MB 855328) for the new species, which differs phenotypically from M. marina, M. plantarum and M. pileae in its ability to assimilate methyl-α-d-glucoside and the inability to assimilate salicin, and from M. nashicola in its ability to assimilate nitrate and nitrite and grow at 30 °C.

The Hidden Global Diversity of the Yeast Genus Carlosrosaea: A Biodiversity Databases Perspective

Biodiversity gaps in microorganisms, such as yeasts, blur our understanding of microbial diversity, introducing biases in their biogeography, ecology, and taxonomy. The genus Carlosrosaea is a potential plant growth booster, yet it is still a little-known yeast group. Considering that databases like GBIF and GenBank are powerful tools for exploring biodiversity data, we aimed to map the geographic distribution, ecological patterns, and taxonomic potential of the genus Carlosrosaea. We found 176 records of the genus, with about 70% associated with plant material, mostly leaves. Furthermore, 55% of the records pertained to the tropical region and only 12% to the temperate. The data indicates the existence of more than a dozen possible new species of the genus, cataloged yet undescribed. This study advances our understanding of the geographic, ecological, and taxonomic aspects of Carlosrosaea. It also highlights how public databases and literature reviews provide accessible ways to analyze information about microbial groups with limited data.

Classes and phyla of the kingdom Fungi

Fungi are one of the most diverse groups of organisms with an estimated number of species in the range of 2–3 million. The higher-level ranking of fungi has been discussed in the framework of molecular phylogenetics since Hibbett et al., and the definition and the higher ranks (e.g., phyla) of the ‘true fungi’ have been revised in several subsequent publications. Rapid accumulation of novel genomic data and the advancements in phylogenetics now facilitate a robust and precise foundation for the higher-level classification within the kingdom. This study provides an updated classification of the kingdom Fungi, drawing upon a comprehensive phylogenomic analysis of Holomycota, with which we outline well-supported nodes of the fungal tree and explore more contentious groupings. We accept 19 phyla of Fungi, viz. Aphelidiomycota, Ascomycota, Basidiobolomycota, Basidiomycota, Blastocladiomycota, Calcarisporiellomycota, Chytridiomycota, Entomophthoromycota, Entorrhizomycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota, Sanchytriomycota, and Zoopagomycota. In the phylogenies, Caulochytriomycota resides in Chytridiomycota; thus, the former is regarded as a synonym of the latter, while Caulochytriomycetes is viewed as a class in Chytridiomycota. We provide a description of each phylum followed by its classes. A new subphylum, Sanchytriomycotina Karpov is introduced as the only subphylum in Sanchytriomycota. The subclass Pneumocystomycetidae Kirk et al. in Pneumocystomycetes, Ascomycota is invalid and thus validated. Placements of fossil fungi in phyla and classes are also discussed, providing examples.

Vishniacozyma floricola sp. nov., a flower-related tremellomycetous yeast species from Europe

During the course of two independent studies conducted in Hungary and Spain, four conspecific yeast strains were isolated from flowers of different plant species. DNA sequences of two barcoding regions, the D1/D2 domain of the LSU rRNA gene and the internal transcribed spacer (ITS) region (ITS1-5.8S rRNA gene-ITS2), revealed that the four strains represent an undescribed Vishniacozyma (family Bulleribasidiaceae, Basidiomycota) species. In terms of pairwise sequence similarities and according to our phylogenetic analyses of the concatenated DNA sequences of the ITS region and the D1/D2 domain of the LSU rRNA gene, the undescribed species is most closely related to Vishniacozyma melezitolytica, a yeast species of phylloplane origin. The novel species differs from the type strain of V. melezitolytica by 8 substitutions and 3 insertion/deletion (indels) and 11 substitutions and 5 indels along the D1/D2 domain of the LSU rRNA gene and the ITS region, respectively. In addition to the DNA sequence divergences, the two species differ in some physiological characters as well. We propose the species Vishniacozyma floricola sp. nov. to accommodate the above-noted strains (holotype, NCAIM Y.02320; isotype, CBS 18939; MycoBank number, 856028).