Diversity of Wickerhamomyces (Wickerhamomycetaceae, Saccharomycetales) in China with the description of four new species.

Wickerhamomyces is a well-known genus of the family Wickerhamomycetaceae in the class Ascomycetes. These fungi can survive in a variety of substrates and environments and perform many valuable roles in both industrial processes and the natural ecosystems. During our investigation of yeast diversity associated with plant materials, 53 Wickerhamomyces isolates were obtained from rotting wood and plant leaves collected in Fujian, Guizhou, Henan, and Yunnan Provinces of China. Isolates were identified as 14 Wickerhamomyces species, including 1 species known previously to occur in China (W. anomalus), 9 new record species in China (W. arborarius, W. ciferrii, W. edaphicus, W. lynferdii, W. pijperi, W. subpelliculosa, W. xylosica, W. strasburgensis, and W. sydowiorum), and 4 novel species (W. guiyangensis sp. nov., W. paramyanmarensis sp. nov., W. quanzhouensis sp. nov., and W. phyllophilus sp. nov.). This study presents a detailed account of these new species, illustrating their morphology and analyzing their phylogenetic relationships with other Wickerhamomyces species. Our study is the first comprehensive study on Wickerhamomyces species associated with plant materials from tropical and subtropical China. The results of this study update our understanding of the phylogenetic relationships, systematics, and ecology of Wickerhamomyces.

Two new Erythrobasidium species inhabiting the phyllosphere discovered in the Baotianman Nature Reserve in China.

The genus Erythrobasidium is kind of species-scarce and undersampling basidiomycetes. Currently, only six species have been accepted into the genus and the diversity still remains incompletely understood. In this study, five Erythrobasidium strains were isolated in the surface of plant leaves collected from the Baotianman Nature Reserve, Henan Province, central China. Phylogenetic analyses of the small ribosomal subunit (SSU) rRNA gene, the internal transcribed spacer (ITS) region, the D1/D2 domain of the large subunit (LSU) rRNA gene, and the translation elongation factor 1-α (TEF1-α) gene coupled with morphological studies were employed to characterize and identify these isolates. As a result of these, two new species, namely E. turpiniae sp. nov. and E. nanyangense sp. nov., were delimited and proposed based on morphological and molecular evidence. A detailed description and illustration of both new species, as well as their differences with the close relatives in the genus are provided. An identification key for Erythrobasidium species is also provided. This study provides further insights into our understanding of Erythrobasidium species.

Two new phyllospheric species of Colacogloea (Colacogloeaceae, Pucciniomycotina) identified in China.

During our ongoing survey of basidiomycetous yeasts associated with plant leaves in virgin forest, five Colacogloea strains were isolated in the Baotianman Nature Reserve, Henan Province, central China. Phenotypes from cultures and a phylogeny based on the internal transcribed spacer (ITS) regions and the D1/D2 domains of the large subunit (LSU) rRNA gene were employed to characterize and identify these isolates. As a result, two new species, namely Colacogloeaceltidissp. nov. and C.pararetinophilasp. nov., are introduced herein. In the phylogeny of combined ITS and LSU dataset, the new species C.celtidissp. nov. formed a clade with the unpublished Colacogloea strain (KBP: Y-6832), and together these formed the sister group to C.armeniacae, while C.pararetinophilasp. nov. was retrieved as a sister to C.retinophila. A detailed description and illustration of both new species, as well as the differences between them and their closest relatives in the genus are provided. Results from the present study will add to our knowledge of the biodiversity of Colacogloea in China.

Spencerozyma pingqiaoensis sp. nov., a yeast species isolated from the external surface of rice leaves in China.

Four strains (NYNU 178247, NYNU 178251, DMKU-PAL160 and DMKU-PAL137) representing a novel yeast species were isolated from the external surfaces of rice and pineapple leaves collected in China and Thailand. Phylogenetic analysis based on the concatenated sequences of the internal transcribed spacer (ITS) regions and the D1/D2 domains of the large subunit rRNA gene revealed that the novel species belonged to the genus Spencerozyma. The D1/D2 sequence of the novel species differed from its closest relative, Spencerozyma acididurans SYSU-17T, by 3.2 % sequence divergence. The species also differed from Spencerozyma crocea CBS 2029T and Spencerozyma siamensis DMKU13-2T, by 3.0-6.9 % sequence divergence in the D1/D2 sequences out of 592 bp. In the ITS regions, the novel species displayed 19.8-29.2% sequence divergence from S. acididurans SYSU-17T, S. crocea CBS 2029T and S. siamensis DMKU13-2T out of 655 bp. Furthermore, the novel species could also be differentiated from the closely related species by some physiological characteristics. The species name of Spencerozyma pingqiaoensis sp. nov. (Holotype CBS 15238, Mycobank MB 844734) is proposed to accommodate these four strains.

Multi-gene phylogeny and taxonomy of the genus Bannoa with the addition of three new species from central China.

The genus Bannoa is a small group of ballistoconidium-forming yeasts in the family Erythrobasidiaceae (Cystobasidiomycetes). Prior to this study, seven species belonging to this genus have been described and published. In this study, phylogenetic analyzes of Bannoa based on the combined sequences of the small ribosomal subunit (SSU) rRNA gene, the internal transcribed spacer (ITS) regions, the D1/D2 domains of the large subunit rRNA gene (LSU) and the translation elongation factor 1-α gene (TEF1-α) were conducted. Three new species, namely B. ellipsoidea, B. foliicola, and B. pseudofoliicola, were delimited and proposed based on morphological and molecular evidence. B. ellipsoidea was found to be closely related to the type strains of B. guamensis, B. hahajimensis, and B. tropicalis, but with 0.7-0.9% divergence (4-5 substitutions) in the LSU D1/D2 domains and 3.7-4.1% divergence (19-23 substitutions and one-two gaps) in the ITS regions. B. foliicola was found to belong to the same clade as B. pseudofoliicola from which it differed by 0.4% divergence (two substitutions) in the LSU D1/D2 domains and 2.3% divergence (13 substitutions) in the ITS regions. The distinguishing morphological characteristics of the three new species, with respect to closely related taxa, are discussed. The identification of these new taxa significantly increases the number of Bannoa that have been described on the surface of plant leaves. Additionally, a key for the identification of Bannoa species is provided.

Corrigendum: Phylogenetic and genomic analyses of two new species of Clavispora (Metschnikowiaceae, Saccharomycetales) from Central China.

[This corrects the article DOI: 10.3389/fmicb.2022.1019599.].

Phylogenetic and genomic analyses of two new species of Clavispora (Metschnikowiaceae, Saccharomycetales) from Central China.

Species in the genus Clavispora have previously been reported primarily in the northeast and northwest regions of China; the species diversity of Clavispora in central China is not currently clear. In this study, phylogenetic inferences of Clavispora based on sequences of a single-locus (LSU D1/D2) and a two-locus (LSU D1/D2 and ITS) were conducted. Two new species isolated from rotting wood in central China, namely Clavispora xylosa sp. nov. and Clavispora paralusitaniae sp. nov., were delimited and proposed based on morphological and molecular evidence. Cl. xylosa was closely related to C. thailandica CBS 10610T, but with 11.5% divergence in the LSU D1/D2 domains and 11.5% divergence in the ITS regions. Cl. paralusitaniae was a sister to Cl. lusitaniae CBS 6936T from which it differs with 4.7% divergence in the LSU D1/D2 domains and 5.4% divergence in the ITS regions. Description of Cl. xylosa sp. nov. and Cl. paralusitaniae sp. nov. was also supported by morphological comparisons and genomic analyses between the two new species and their closest relatives, C. thailandica CBS 10610T and Cl. lusitaniae CBS 6936T. These results indicate a potentially great diversity of Clavispora spp. inhabiting rotting wood in central China, ripe for future discovery.

Four new species of Trichomonascaceae (Saccharomycetales, Saccharomycetes) from Central China.

Trichomonascaceae is the largest family of ascomycetous yeast in the order Saccharomycetales. In spite of the extensive body of research on Trichomonascaceae in China, there remain new species to be discovered. Here, we describe four new species isolated from several rotting wood samples from Henan Province, Central China. Phylogenetic analysis of a combined ITS and nrLSU dataset with morphological studies revealed four new species in the Trichomonascaceae: Diddensiellaluoyangensis, Sugiyamaellacylindrica, Su.robnettiae, and Zygoascusdetingensis. Clustering in the Diddensiella clade, D.luoyangensis' closest neighbour was D.transvaalensis. Meanwhile, Su.cylindrica clustered in the Sugiyamaella clade closest to Su.marilandica and Su.qingdaonensis. Also clustering in the Sugiyamaella clade, Su.robnettiae was most closely related to Su.chuxiongensis. Finally, Z.detingensis occupied a distinct and separated basal branch from the other species of the genus Zygoascus. These results indicate a high species diversity of Trichomonascaceae.

Kodamaeahongheensis f.a., sp. nov., Kodamaeaovata f.a., sp. nov. and Kodamaeayamadae f.a., sp. nov., three new yeast species of Kodamaea (Saccharomycetales, Debaryomycetacae) from China.

Kodamaea includes a growing number of interesting yeasts of the family Debaryomycetacae that are widely distributed in temperate, subtropical and tropical regions of different continents. During recent yeast collections in Henan and Yunnan Province in China, several isolates of Kodamaea were obtained from rotting wood, all of which represent undescribed taxa. Based on morphological and phylogenetic analyses (ITS and LSU rDNA), three new species are proposed: K.hongheensis f.a., sp. nov., K.ovata f.a., sp. nov. and K.yamadae f.a., sp. nov. In addition, sixteen Candida species, which are members of the Kodamaea clade based on phylogenetic analysis, are transferred to Kodamaea as new combinations. Our results indicate high species diversity of Kodamaea waiting to be discovered in rotting wood from tropical and subtropical China.

New species of Yamadazyma from rotting wood in China.

Yamadazyma is one of the largest genera in the family Debaryomycetaceae (Saccharomycetales, Saccharomycetes) with species mainly found in rotting wood, insects and their resulting frass, but also recovered from flowers, leaves, fruits, tree bark, mushrooms, sea water, minerals, and the atmosphere. In the present study, several strains obtained from rotting wood in Henan and Yunnan Provinces of China were isolated. Based on morphology and a molecular phylogeny of the rDNA internal transcribed spacer region (ITS) and the D1/D2 domain of the large subunit (LSU) rDNA, these strains were identified as three new species: Yamadazymaluoyangensis, Y.ovata and Y.paraaseri; and three previously described species, Y.insectorum, Y.akitaensis, and Y.olivae. The three new species are illustrated and their morphology and phylogenetic relationships with other Yamadazyma species are discussed. Our results indicate a high undiscovered diversity of Yamadazyma spp. inhabiting rotting wood in China.

Diversity of the genus Sugiyamaella and description of two new species from rotting wood in China.

Species of the genus Sugiyamaella (Trichomonascaceae, Saccharomycetales), found in rotting wood in China, were investigated using morphology and the molecular phylogeny of a combined ITS and nrLSU dataset. Nine taxa were collected in China: two were new species (viz. Sugiyamaella chuxiong sp. nov. and S. yunanensis sp. nov.) and seven were known species, S. americana, S. ayubii, S. novakii, S. paludigena, S. valenteae, S. valdiviana and S. xiaguanensis. The two new species are illustrated and their morphology and phylogenetic relationships with other Sugiyamaella species are discussed. Our results indicate a potentially great diversity of Sugiyamaella spp. inhabiting rotting wood in China just waiting to be discovered.

Five new additions to the genus Spathaspora (Saccharomycetales, Debaryomycetaceae) from southwest China.

Spathaspora is an important genus of d-xylose-fermenting yeasts that are poorly studied in China. During recent yeast collections in Yunnan Province in China, 13 isolates of Spathaspora were obtained from rotting wood and all represent undescribed taxa. Based on morphological and phylogenetic analyses (ITS and nuc 28S), five new species are proposed: Spathaspora elongata, Sp. mengyangensis, Sp. jiuxiensis, Sp. parajiuxiensis and Sp. rosae. Our results indicate a high species diversity of Spathaspora waiting to be discovered in rotting wood from tropical and subtropical southwest China. In addition, the two Candida species, C. jeffriesii and C. materiae, which are members of the Spathaspora clade based on phylogeny, are transferred to Spathaspora as new combinations.

Mrakia panshiensis sp. nov. a new member of the Cystofilobasidiales from soil in China, and description of the teleomorphic-stage of M. arctica.

In a study on the fungal diversity in Northeast China, twelve yeast isolates were obtained from soils collected in three provinces, Helongjiang, Jilin and Liaoning. Morphological assessment and phylogenetic analyses of the nuc rDNA internal transcribed spacer (ITS) region and the D1/D2 domains of the nuc 28S rDNA (nuc 28S) gene of the 12 cultures placed them in the genus Mrakia, namely Mrakia aquatica, Mrakia arctica, Mrakia frigida, Mrakia gelida and Mrakia robertii. A total of three isolates represented a hitherto undescribed species, which is described here as M. panshiensis sp. nov. (MB 834813). The species M. panshiensis sp. nov. shares several morphological characters with M. niccombsii, M. aquatica, M. fibulata and M. hoshinonis. These species can be distinguished based on physiological traits and pairwise rDNA sequence similarities. The study also describes for the first time the formation of teliospores by previously described M. arctica.

Three new Scheffersomyces species associated with insects and rotting wood in China.

Three species of Scheffersomyces were identified during a diversity study of yeasts. All three are associated with insects and rotting wood in China. Phylogenetic analyses of a genomic dataset combining ITS and nrLSU revealed that these new collections are distinct from known species, thus three new species are introduced i.e. S. jinghongensis, S. paraergatensis, and S. anoplophorae. In our phylogenetic analyses, Scheffersomyces jinghongensis possesses a strong independent lineage and is closely related to S. titanus. S. paraergatensis is closely related to S. ergatensis, while S. anoplophorae is related to S. stambukii. Several differences in physiological traits and molecular data indicate that S. jinghongensis, S. paraergatensis, and S. anoplophorae are three newly identified species.

Blastobotrys baotianmanensis sp. nov. and Blastobotrys xishuangbannaensis f.a., sp. nov., two novel yeast species associated with insects and rotting wood.

Five yeast strains were isolated from the gut of the groundbeetle Pterostichus gebleri and rotting wood, which were collected from two different localities in China. These strains were identified as representing two novel species of the genus Blastobotrys through comparison of sequences in the D1/D2 domains of the LSU rRNA gene and other taxonomic characteristics. Blastobotrys baotianmanensis sp. nov. produces two to three spherical ascospores per ascus, and is most closely related to the type strains of B. elegans, B. capitulata, B. arbuscula, and an undescribed species represented by strain BG02-7-20-006A-3-1. Blastobotrys baotianmanensis sp. nov. differed from these strains by 3.6-8.4 % divergence (21-46 substitutions and 0-4 gaps) in the D1/D2 sequences. Blastobotrys xishuangbannaensis f.a., sp. nov. is closely related to B. nivea, B. elegans and B. aristata but the formation of ascospores was not observed on various sporulation media, and it differed from its relatives by 6.2-8.5 % divergence (34-43 substitutions and 2-6 gaps) in the D1/D2 sequences. The holotype of Blastobotrys baotianmanensis sp. nov. is NYNU 1581 and the holotype of Blastobotrys xishuangbannaensis f.a., sp. nov. is NYNU 181030.

Metschnikowia baotianmanensis f.a., sp. nov., a new yeast species isolated from the gut of the rhinoceros beetle Allomyrina dichotoma.

Four strains, NYNU 15610, NYNU 15612, NYNU 15613 and NYNU 15615, of a novel ascomycetous yeast were isolated from the gut of Allomyrina dichotoma (Coleoptera: Scarabeidae) collected from two different localities in Henan Province, Central PR China. The four strains shared identical sequences in both of the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer regions. Sequence analyses revealed that this novel species represents a member of the genus Metschnikowia. It differed from its closest known species Metschnikowia zobellii, Metschnikowiaaustralis and Metschnikowia bicuspidata, by 8.4-9.2 % sequence divergence (33-40 nt substitutions and 7-12 gaps over 509 bases) in the D1/D2 sequences. The formation of ascospores was not observed on various sporulation media. In contrast to M. zobellii, M. australis and M. bicuspidata, the novel yeast species was unable to assimilate succinate, ethanol, ethylamine, cadaverine and 10 % NaCl plus 5 % glucose, but was able to grow in vitamin-free medium. The name Metschnikowia baotianmanensis f.a., sp. nov. is proposed to accommodate these strains, with NYNU 15613 as the holotype.

Saturnispora galanensis sp. nov., a yeast species isolated from rotting wood.

Three strains of a novel yeast species were isolated from rotting wood in the Xishuangbanna Tropical Rainforest, Yunnan Province, PR China. Sequence analysis of the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions showed that the novel species represents a member of the genus Saturnispora. It differed from its closest known species, Saturnispora sekii CBS 10931T, by 1.3 % nucleotide substitutions in the D1/D2 domains and by 2.2 % nucleotide substitutions in the ITS regions, respectively. In contrast to Saturnispora sekii, the novel yeast species was unable to assimilate glycerol, dl-lactate, succinate and citrate, and grow at 37 °C. The name Saturnispora galanensis sp. nov. is proposed to accommodate these strains, with NYNU 1797 as the holotype.

Candida yunnanensis sp. nov. and Candida parablackwelliae sp. nov., two yeast species in the Candida albicans/Lodderomyces clade.

During studies on the yeast communities associated with rotting wood in the Xishuangbanna Tropical Rainforest in PR China, four novel yeast strains were found. Phylogenetic analysis based on the concatenated sequences of the D1/D2 domains of the large subunit rRNA gene and the ITS regions showed that these strains represented two novel species in the Candida albicans/Lodderomyces clade. The novel species, represented by strains NYNU 17948 and NYNU 17981, formed a clade with Candida maltosa and Candida baotianmanensis, with 1-1.8% sequence divergence in the D1/D2 domains and 8.9-10% sequence divergence in the ITS regions. The other novel species, represented by NYNU 17105 and NYNU 17763, is most closely related to Candida blackwelliae with 0.7 % sequence divergence in the D1/D2 domains and 6.9 % sequence divergence in the ITS regions. The two novel species could be distinguished from their closest described species in terms of physiological traits. The two novel species are described as Candida yunnanensis sp. nov. (holotype NYNU 17948) and Candida parablackwelliae sp. nov. (holotype NYNU 17763).

Wickerhamomyces menglaensis f.a., sp. nov., a yeast species isolated from rotten wood.

Five strains, NUNU 16637, NYNU 16645, NYNU 1673, NYNU 1680 and NYNU 1689, of a novel ascomycetous yeast were isolated from the Xishuangbanna tropical rainforest, Yunnan Province, PR China. The five strains shared identical sequences in both of the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions. Sequence analysis showed that they represent undescribed yeast species belonging to the genus Wickerhamomyces. They differed from their closest known species, Wickerhamomyces xylosivorus NBRC 111553T, by 3.4 % sequence divergence (14 substitutions and six gaps out of 584 bp) in the D1/D2 domains and by 9.6 % sequence divergence (28 substitutions and 24 gaps over 543 bp) in the ITS regions, respectively. The five strains of novel species reproduced asexually; no sexual reproduction could be found. In contrast to W. xylosivorus, the novel yeast species were able to assimilate l-arabinose, inulin, soluble starch, d-mannitol and citrate, and unable to assimilate trehalose, raffinose, 5-keto-d-gluconate, d-gluconate, ethanol, ethylamine and cadaverine. Growth was observed at 35 °C. The name Wickerhamomyces menglaensis f.a., sp. nov. is proposed to accommodate these strains, with NYNU 1673 as the holotype.