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A set of four strains representing a novel basidiomycetous yeast species Rhodotorula sampaioana f. a., sp. nov. were isolated from two different habitats, subsurface waters of Lake Negra in Argentina, and the gut of a xylophagous termite in India. Phylogenetic analyses of LSU and ITS sequences showed that they belonged to the genus Rhodotorula of the order Sporidiobolales (subphylum Pucciniomycotina) and the closest known relative being R. kratochvilovae. The new species differed from R. kratochvilovae CBS 7436 (AF071436, AF444520) by nine nucleotide substitutions and one deletion (1.7 % sequence variation) in a 593 bp D1/D2 region, and by five nucleotide substitutions and three deletions (1.3 %) in a 592 bp ITS region, respectively. Several morphological and physiological differences were also observed between R. kratochvilovae and the strains obtained during this study. These data support the proposal of Rhodotorula sampaioana as a novel species, with CRUB 1124 as the holotype, CBS 10798 as ex-type, and NFCCI 4872 as an additional strain. The GenBank accession numbers of the LSU and ITS sequences of Rhodotorula sampaioana f. a., sp. nov. are EF595748 and MW879331. The MycoBank number is MB 838533.

The identity of Achroomyces effusus is re-established with the use of morphological and DNA methods, and a neotype is selected. The species is conspecific with Colacogloea peniophorae, the generic type of Colacogloea, and has a priority over it. A new combination, C. effusa, is proposed.

Funding Information: We thank Prof. Jian-Yun Zhuang for his advice on nomenclatural matters. We thank Dr. Alexander Idnurm for his kindly providing the sequences and informations of strain IAM13481 and his critical comments for this manuscript, Dr. Aleksey Kachalkin for his sharing the physilogical data of strain KBP Y-5548 and Masako Takashima for her sharing the physilogical data of strain TY-217. We also thank Ana Pontes and Cl?udia Carvalho for editing illustrations of Kondoa myxariophila and for ITS sequencing, respectively. This study was supported by grants No. 31570016 from the National Natural Science Foundation of China (NSFC) and national project on scientific groundwork No. 2014FY210400 from the Ministry of Science and Technology of China. The authors are solely responsible for the content of this work. Nearly 500 basidiomycetous yeast species were accepted in the latest edition of The Yeasts: A Taxonomic Study published in 2011. However, this number presents only the tip of the iceberg of yeast species diversity in nature. Possibly more than 99 % of yeast species, as is true for many groups of fungi, are yet unknown and await discovery. Over the past two decades nearly 200 unidentified isolates were obtained during a series of environmental surveys of yeasts in phyllosphere and soils, mainly from China. Among these isolates, 107 new species were identified based on the phylogenetic analyses of nuclear ribosomal DNA (rDNA) [D1/D2 domains of the large subunit (LSU), the small subunit (SSU), and the internal transcribed spacer region including the 5.8S rDNA (ITS)] and protein-coding genes [both subunits of DNA polymerase II (RPB1 and RPB2), the translation elongation factor 1-α (TEF1) and the mitochondrial gene cytochrome b (CYTB)], and physiological comparisons. Forty-six of these belong to 16 genera in the Tremellomycetes (Agaricomycotina). The other 61 are distributed in 26 genera in the Pucciniomycotina. Here we circumscribe eight new genera, three new families and two new orders based on the multi-locus phylogenetic analyses combined with the clustering optimisation analysis and the predicted similarity thresholds for yeasts and filamentous fungal delimitation at genus and higher ranks. Additionally, as a result of these analyses, three new combinations are proposed and 66 taxa are validated. publishersversion published

Fungi of the order Pucciniales are obligate plant biotrophs causing rust diseases. They exhibit a complex life cycle with the production of up to five spore types, infection of two unrelated hosts and an overwintering stage. Transcription factors (TFs) are key regulators of gene expression in eukaryote cells. In order to better understand genetic programs expressed during major transitions of the rust life cycle, we surveyed the complement of TFs in fungal genomes with an emphasis on Pucciniales. We found that despite their large gene numbers, rust genomes have a reduced repertoire of TFs compared to other fungi. The proportions of C2H2 and Zinc cluster - two of the most represented TF families in fungi-indicate differences in their evolutionary relationships in Pucciniales and other fungal taxa. The cold shock protein (CSP) family showed a striking expansion in Pucciniomycotina with specific duplications in the order Pucciniales. The survey of expression profiles collected by transcriptomics along the life cycle of the poplar rust fungus revealed TF genes related to major biological transitions, e.g. response to environmental cues and host infection. Particularly, poplar rust CSPs were strongly expressed in basidia produced after the overwintering stage suggesting a possible role in dormancy exit. Expression during transition from dormant telia to basidia confirmed the specific expression of the three poplar rust CSP genes. Their heterologous expression in yeast improved cell growth after cold stress exposure, strengthening their implication in dormancy exit. This study addresses for the first time TF involved in developmental transition in the rust life cycle opening perspectives to further explore molecular regulation in the biology of the Pucciniales.

A long-standing question about the early evolution of club fungi (phylum Basidiomycota) is the relationship between the three major groups, Pucciniomycotina, Ustilaginomycotina and Agaricomycotina. It is unresolved whether Agaricomycotina are more closely related to Ustilaginomycotina or to Pucciniomycotina. Here we reconstructed the branching order of the three subphyla through two sources of phylogenetic signals, i.e. standard phylogenomic analysis and alignment-free phylogenetic approach. Overall, beyond congruency within the frame of standard phylogenomic analysis, our results consistently and robustly supported the early divergence of Ustilaginomycotina and a closer relationship between Agaricomycotina and Pucciniomycotina. Keywords: Fungi, Basidiomycota, Phylogenetics, Phylogenomics, CVTree

Infections caused by Rhodotorula spp. are increasing worldwide. This study identified, through the light of the new taxonomic advances on the subphylum Pucciniomycotina, 16 isolates from blood cultures and compared their antifungal susceptibility on microdilution and gradient diffusion methods. Internal transcriber spacer sequencing identified Rhodotorula mucilaginosa (n = 12), Rhodotorula toruloides (n = 2), Rhodotorula dairenensis (n = 1), and Cystobasidium minutum (n = 1). Amphotericin B was the most effective drug. A good essential agreement was observed on MIC values of amphotericin B and voriconazole determined by the two methods. Therefore, the gradient method is useful for susceptibility tests of R. mucilaginosa against these drugs. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-019-00191-2) contains supplementary material, which is available to authorized users.

The Basidiomycota constitutes a major phylum of the kingdom Fungi and is second in species numbers to the Ascomycota. The present work provides an overview of all validly published, currently used basidiomycete genera to date in a single document. An outline of all genera of Basidiomycota is provided, which includes 1928 currently used genera names, with 1263 synonyms, which are distributed in 241 families, 68 orders, 18 classes and four subphyla. We provide brief notes for each accepted genus including information on classification, number of accepted species, type species, life mode, habitat, distribution, and sequence information. Furthermore, three phylogenetic analyses with combined LSU, SSU, 5.8s, rpb1, rpb2, and ef1 datasets for the subphyla Agaricomycotina, Pucciniomycotina and Ustilaginomycotina are conducted, respectively. Divergence time estimates are provided to the family level with 632 species from 62 orders, 168 families and 605 genera. Our study indicates that the divergence times of the subphyla in Basidiomycota are 406–430 Mya, classes are 211–383 Mya, and orders are 99–323 Mya, which are largely consistent with previous studies. In this study, all phylogenetically supported families were dated, with the families of Agaricomycotina diverging from 27–178 Mya, Pucciniomycotina from 85–222 Mya, and Ustilaginomycotina from 79–177 Mya. Divergence times as additional criterion in ranking provide additional evidence to resolve taxonomic problems in the Basidiomycota taxonomic system, and also provide a better understanding of their phylogeny and evolution.

Strain SYSU-17, representing a novel acid-tolerant yeast species which can grow at pH 2.0 weakly, was isolated from acid mine drainage collected in a tailing impoundment of the Fankou Lead/Zinc Mine, Guangdong Province, PR China. Phylogenetic analysis of strain SYSU-17 based on the internal transcribed spacer (ITS) region and the D1/D2 domains of the large subunit ribosomal RNA (LSU rRNA) gene suggested that strain SYSU-17 was a novel species belonging to the genus Spencerozyma (class Microbotryomycetes, subphylum Pucciniomycotina). It differed from the type strain of the closest related species, Spencerozyma crocea CBS 2029T, by 0.7 % sequence divergence (three gaps and one nucleotide substitution out of 594 bp) in the D1/D2 domains of the LSU rRNA gene and 7.6 % sequence divergence (32 gaps and 22 nucleotide substitutions out of 714 bp) in the ITS region. In contrast to the physiological properties of S. crocea, the novel yeast species was unable to assimilate galactose, d-ribose, xylitol, succinate, d-xylose, ethanol, nitrate and nitrite. The name Spencerozyma acididurans sp. nov. is proposed and SYSU-17 is designated as the holotype.

The diversity of yeasts has grown rapidly as the discovery of new species has benefited from intensified sampling and largely improved identification techniques. An environmental study typically reports the isolation of yeast species, some of which are new to science. Rare species represented by a few isolates often do not result in a taxonomic description. Nucleic acid sequences from these undescribed yeasts remain in public sequence databases, often without a proper taxonomic placement. This study presents a constrained phylogenetic analysis for many rare yeasts from unpublished but publicly available DNA sequences and from studies previously conducted by the authors of this work. We demonstrate that single isolates are an important source of taxonomic findings such as including new genera and species. Independent surveys performed during the last 20 years on a large geographic scale yielded a number of single strains, which were proved to be conspecific in the phylogenetic analyses presented here. The following new species were resolved and described: Vustinia terrea Kachalkin, Turchetti & Yurkov gen. nov. et sp. nov.; Udeniomyces caspiensis Kachalkin sp. nov.; Udeniomyces orazovii Kachalkin sp. nov.; Tausonia rosea Kachalkin sp. nov.; Itersonilia diksonensis Kachalkin sp. nov.; Krasilnikovozyma fibulata Glushakova & Kachalkin, Kwoniella fici Turchetti sp. nov.; Heterocephalacria fruticeti f.a. Carvalho, Roehl, Yurkov & Sampaio sp. nov.; Heterocephalacria gelida f.a. Turchetti & Kachalkin sp. nov.; Heterocephalacria hypogea f.a. Carvalho, Roehl, Yurkov & Sampaio sp. nov.; Heterocephalacria lusitanica f.a. Inacio, Carvalho, Roehl, Yurkov & Sampaio sp. nov.; Piskurozyma arborea Yurkov, Kachalkin, Masinova & Baldrian sp. nov.; Piskurozyma silvicultrix Turchetti, Masinova, Baldrian & Yurkov sp. nov.; Piskurozyma stramentorum Yurkov, Masinova & Baldrian sp. nov.; Naganishia nivalis Turchetti sp. nov.; and Yurkovia nerthusi Yurkov & Begerow, sp. nov. In addition, two new combinations were proposed Krasilnikovozyma curviuscula (Babeva, Lisichkina, Reshetova & Danilevich) Yurkov, Kachalkin & Sampaio comb. nov. and Hannaella taiwanensis (F.L. Lee & C.H. Huang) Yurkov comb. nov. The order Cyphobasidiales T. Spribille & H. Mayrhofer is rejected in favor of the older name Erythrobasidiales R. Bauer, Begerow, J.P. Sampaio, M. Weiss & Oberwinkler. Other potential novel species identified in this paper await future description. Phylogenetic placement of yet unpublished sequences is believed to facilitate species descriptions and improve classification of yeasts from environmental sequence libraries.

Sampling campaigns in Greenland and Svalbard were executed to explore fungal diversity in cold habitats. Three very abundant groups of strains were discovered, consisting either of recently described or of yet-undescribed psychrophilic and oligotrophic yeasts and dimorphic fungi, accounting for around 50 % of the total cultivable diversity of basidiomycetes in our studies. The occurrence of these taxa has also been demonstrated by culture-independent methods. Based on phylogenetic analyses of ribosomal gene cluster sequences (D1/D2 domains of 28S (LSU), 18S (SSU), ITS with 5.8S rDNA) and sequences of protein-coding genes for elongation factor one alpha (TEF), cytochrome b (CYTB) and two subunits of the RNA polymerase II (RPB1 and RPB2) obtained from pure cultures, the isolated taxa presented in this study belong to Basidiomycota, subphylum Pucciniomycotina, class Microbotryomycetes, family Camptobasidiaceae. The dataset of the sequences supported the recognition of three species: Camptobasidium gelus, Camptobasidium arcticum sp. nov. (ex-type strain EXF-12713) and Psychromyces glacialis gen. and sp. nov. (ex-type strain EXF-13111). Camptobasidium gelus was found in the Svalbard and Greenland samples, while representatives of the here proposed new species, C. arcticum, were found only in the Greenland Ice Sheet. Psychromyces gen. nov. was erected for the dimorphic/filamentous isolates found in Svalbard and Greenland glacial environments. The taxon, for which the invalid name ‘Rhodotorula svalbardensis’ has been used, belongs to this genus. Based on ribosomal genes, Camptobasidium arcticum and Psychromyces glacialis are related, phylogenetically most closely related to the genera Glaciozyma and Cryolevonia. Seven genes phylogeny restricted to taxa with available sequences, supported the placement of Psychromyces to Camptobasidiaceae.

The lichenicolous ‘heterobasidiomycetes’ belong in the Tremellomycetes (Agaricomycotina) and in the Pucciniomycotina. In this paper, we provide an introduction and review of these lichenicolous taxa, focusing on recent studies and novelties of their classification, phylogeny and evolution. Lichen-inhabiting fungi in the Pucciniomycotina are represented by only a small number of species included in the genera Chionosphaera, Cyphobasidium and Lichenozyma. The phylogenetic position of the lichenicolous representatives of Chionosphaera has, however, never been investigated by molecular methods. Phylogenetic analyses using the nuclear SSU, ITS, and LSU ribosomal DNA markers reveal that the lichenicolous members of Chionosphaera form a monophyletic group in the Pucciniomycotina, distinct from Chionosphaera and outside the Chionosphaeraceae. The new genus Crittendenia is described to accommodate these lichen-inhabiting species. Crittendenia is characterized by minute synnemata-like basidiomata, the presence of clamp connections and aseptate tubular basidia from which 4–7 spores discharge passively, often in groups. Crittendenia, Cyphobasidium and Lichenozyma are the only lichenicolous lineages known so far in the Pucciniomycotina, whereas Chionosphaera does not include any lichenicolous taxa.

Austropuccinia psidii, originating in South America, is a globally invasive fungal plant pathogen that causes rust disease on Myrtaceae. Several biotypes are recognized, with the most widely distributed pandemic biotype spreading throughout the Asia-Pacific and Oceania regions over the last decade. Austropuccinia psidii has a broad host range with more than 480 myrtaceous species. Since first detected in Australia in 2010, the pathogen has caused the near extinction of at least three species and negatively affected commercial production of several Myrtaceae. To enable molecular and evolutionary studies into A. psidii pathogenicity, we assembled a highly contiguous genome for the pandemic biotype. With an estimated haploid genome size of just over 1 Gb (gigabases), it is the largest assembled fungal genome to date. The genome has undergone massive expansion via distinct transposable element (TE) bursts. Over 90% of the genome is covered by TEs predominantly belonging to the Gypsy superfamily. These TE bursts have likely been followed by deamination events of methylated cytosines to silence the repetitive elements. This in turn led to the depletion of CpG sites in TEs and a very low overall GC content of 33.8%. Compared to other Pucciniales, the intergenic distances are increased by an order of magnitude indicating a general insertion of TEs between genes. Overall, we show how TEs shaped the genome evolution of A. psidii and provide a greatly needed resource for strategic approaches to combat disease spread.

Malassezia species are lipophilic yeasts that are members of the normal mycobiota of the skin and mucosal sites of a variety of homeothermic animals. They are also among the few basidiomycetous fungi, such as some Cryptococcus spp., Rhodotorula spp., and Trichosporon spp., that can produce disease in man and animals. However, in contrast with these other species, which are quite often involved in disseminated infections in immunosuppressed patients, Malassezia yeasts are associated mainly with certain skin diseases [1]. This special lipophilic group of yeasts is unique among the fungi. Phylogenetically, they form a well-defined cluster of skinliving yeasts, surrounded by plant pathogens and phylloplaneinhabiting fungi (e.g., Ustilago, Tilletiopsis). However, the taxonomic position of the genus Malassezia in the classes of the phylum Basidiomycota is not yet totally well defined. Moreover, the sexual form of these yeasts is still unknown. Recently, a region corresponding to the mating type locus (MAT) has been identified for these yeasts, and it has been suggested that if there is an extant sexual cycle for some of these yeasts that it is more likely to be bipolar, with just two mating types, rather than tetrapolar, with many mating types [2]. In the last higher-level fungal phylogenetic classification revision [3], the monophyletic genus Malassezia was the only genus included in the order Malasseziales, which has an uncertain taxonomic position in the subphylum Ustilagomycotina (e.g., smut fungi). Very recently, the class Malasseziomycetes has been proposed to accommodate these fungi (2013, provided from an anonymous reviewer; unreferenced). They are taxonomically distant to the orders which include the other commented pathogenic basidiomycetous yeasts of the genera Cryptococcus (Filobasidiales) and Trichosporon in Agaricomycotina (e.g., mushrooms) and of the polyphyletic genus Rhodotorula (Sporidiobolales and Cystobasidiales) in Pucciniomycotina (e.g., rust fungi).

Our understanding of the systematics of red yeasts has greatly improved with the availability of sequence data and it is now clear that the majority of these fungi belong to three different classes of Pucciniomycotina (Basidiomycota): Agaricostilbomycetes, Cystobasidiomycetes, and Microbotryomycetes. Despite improvements in phylogenetic placement, the taxonomy of these fungi has long been in need of revision and still has not been entirely resolved, partly due to missing taxa. In the present study, we present data of culture-based environmental yeast isolation, revealing several undescribed species of Symmetrospora, which was recently introduced to accommodate six species previously placed in the asexual genera Sporobolomyces and Rhodotorula in the gracilis/marina clade of Cystobasidiomycetes. Based on molecular phylogenetic analyses of three rDNA loci, morphology, and biochemical studies, we formally describe the following new species: Symmetrospora clarorosea sp. nov. from leaf surfaces in Portugal and the USA; S. pseudomarina sp. nov. from leaf surfaces in Brazil, and the USA and decaying wood in the USA; and S. suhii sp. nov. from a beetle gut in the USA, leaf surfaces in Brazil and marine water in the Taiwan and Thailand. Finally, we propose a new combination for Sporobolomyces oryzicola based on our molecular phylogenetic data, Symmetrospora oryzicola comb. nov.

Red yeasts, primarily species of Rhodotorula, Sporobolomyces, and other genera of Pucciniomycotina, are traditionally considered proficient systems for lipid and terpene production, and only recently have also gained consideration for the production of a wider range of molecules of biotechnological potential. Improvements of transgene delivery protocols and regulated gene expression systems have been proposed, but a dearth of information on compositional and/or structural features of genes has prevented transgene sequence optimization efforts for high expression levels. Here, the codon compositional features of genes in six red yeast species were characterized, and the impact that evolutionary forces may have played in shaping this compositional bias was dissected by using several computational approaches. Results obtained are compatible with the hypothesis that mutational bias, although playing a significant role, cannot alone explain synonymous codon usage bias of genes. Nevertheless, several lines of evidences indicated a role for translational selection in driving the synonymous codons that allow high expression efficiency. These optimal synonymous codons are identified for each of the six species analyzed. Moreover, the presence of intragenic patterns of codon usage, which are thought to facilitate polyribosome formation, was highlighted. The information presented should be taken into consideration for transgene design for optimal expression in red yeast species.

Classiculasinensis, isolated from decaying leaves from Mozigou, Chongqing Municipality, China, is described as a new species. The new species is a member of basidiomycetous aquatic hyphomycetes which represent a small proportion of all aquatic hyphomycetes. This species falls within the genus Classicula (Classiculaceae, Pucciniomycotina) and is closely related to C.fluitans, based on multiple gene sequence analyses. Morphologically, it is characterised by the apical, hyaline, obclavate or navicular conidia with several hair-like lateral appendages and by its holoblastic and monoblastic conidiogenesis, with a flat un-thickened conidiogenous locus. Clamp connections and haustorial branches were often observed in culture.

Two new heterobasidiomycetes species belonging to the genera Helicogloea and Spiculogloea (Pucciniomycotina) are described from Belgium. Helicogloea jozefii sp. nov. and Spiculogloea inaequalis sp. nov. are proposed with descriptions and illustrations of macroand microscopical features. The latter species grows as an intrahymenial parasite in Sistotrema spp. Identification keys to the new species are provided for each genus. The newly described species are compared to morphologically similar species and their ecology is briefly discussed. A type study of H. graminicola is included.

Species of Coleosporium (Pucciniales) are rust fungi that typically alternate between pines and angiosperms. In North America, species of Coleosporium often infect Solidago (goldenrods), although their taxonomy on these hosts is unresolved. Joseph. C. Arthur and George B. Cummins regarded these as a single species, Coleosporium solidaginis (fide Arthur) or C. asterum (fide Cummins), but later inoculation studies demonstrated the presence of more than one species, distinguishable by their aecial hosts. A more recent taxonomic study of Coleosporium found that specimens on Solidago identified as C. asterum in North America were not conspecific with the type, which is from Japan, prompting the present study. Herein, we conducted a systematic study on ca. 60 collections of Coleosporium infecting species of Asteraceae from North America using regions of ribosomal DNA and morphology of teliospores and basidia. Our data indicate at least three species of Coleosporium occur on Solidago in North America, C. solidaginis, C. montanum comb. nov., which is proposed for the taxon that has commonly been identified as C. asterum in North America, and C. delicatulum, all of which can be differentiated by morphology of their basidia. In addition, the challenges of marker selection for molecular barcoding of rust fungi is discussed.

The rust fungi (Pucciniales) are the most speciose natural group of plant pathogens, members of which possess the most complex lifecycles in Fungi. How natural selection works on the Pucciniales has been the subject of several hypotheses in mycology. This study uses molecular age estimation using sequence data from multiple loci, and cophylogeny reconciliation analyses to test hypotheses regarding how the aecial and telial stages in the lifecycle of rust fungi may have differentially impacted their diversification. Molecular age estimates show that the timing of diversification in the Pucciniales correlates with the diversification of their gymnosperm and angiosperm hosts. Host reconciliation analyses suggest that systematic relationships of hosts from the aecial stage of the Pucciniales lifecycle better reflect the systematic relationships among the Pucciniales. The results demonstrate the relative importance of this stage on the overall evolution of the Pucciniales and supports hypotheses made by Leppik over half a century ago. This study represents the first evaluation of how different life stages in the Pucciniales shape the evolution of these fungi. Key words: Basidiomycota, Biogenic radiation, Biological specialization, Hologenetic ladder hypothesis, Melampsorineae, Phytopathogenic fungi, Pucciniaceae, Pucciniomycotina, Uredinales

Recent results in taxonomic, phylogenetic and ecological studies of basidiomycetous yeast research are remarkable. Here, Pucciniomycotina with yeast stages are reviewed. The phylogenetic origin of single-cell basidiomycetes still remains unsolved. But the massive occurrence of yeasts in basal basidiomycetous taxa indicates their early evolutionary presence. Yeasts in Cryptomycocolacomycetes, Mixiomycetes, Agaricostilbomycetes, Cystobasidiomycetes, Septobasidiales, Heterogastridiomycetes, and Microbotryomycetes will be discussed. The apparent loss of yeast stages in Tritirachiomycetes, Atractiellomycetes, Helicobasidiales, Platygloeales, Pucciniales, Pachnocybales, and Classiculomycetes will be mentioned briefly for comparative purposes with dimorphic sister taxa. Since most phylogenetic papers suffer considerably from the lack of adequate illustrations, plates for representative species of orders have been arranged. The structural qualities are the prerequisites for specific functions that cannot be expressed by phylogenetic dendrograms.

In this paper, we provide a phylogenetic overview of Basidiomycota and related phyla in relation to ten years of DNA based phylogenetic studies since the AFTOL publications in 2007. We selected 529 species to address phylogenetic relationships of higher-level taxa using a maximum-likelihood framework and sequence data from six genes traditionally used in fungal molecular systematics (nrLSU, nrSSU, 5.8S, tef1-α, rpb1 and rpb2). These species represent 18 classes, 62 orders, 183 families, and 392 genera from the phyla Basidiomycota (including the newly recognized subphylum Wallemiomycotina) and Entorrhizomycota, and 13 species representing 13 classes of Ascomycota as outgroup taxa. We also conducted a molecular dating analysis based on these six genes for 116 species representing 17 classes and 54 orders of Basidiomycota and Entorrhizomycota. Finally we performed a phyloproteomics analysis from 109 Basidiomycota species and 6 outgroup taxa using amino-acid sequences retrieved from 396 orthologous genes. Recognition of higher taxa follows the criteria in Zhao et al (Fungal Divers 78:239–292, 2016): (i) taxa must be monophyletic and statistically well-supported in molecular dating analyses, (ii) their respective stem ages should be roughly equivalent, and (iii) stem ages of higher taxa must be older than those of lower level taxa. The time-tree indicates that the mean of stem ages of Basidiomycota and Entorrhizomycota are ca. 530 Ma; subphyla of Basidiomycota are 406–490 Ma; most classes are 358–393 Ma for those of Agaricomycotina and 245–356 Ma for those of Pucciniomycotina and Ustilaginomycotina; most orders of those subphyla split 120–290 Ma. Monophyly of most higher-level taxa of Basidiomycota are generally supported, especially those taxa introduced in the recent ten years: phylum Entorrhizomycota, classes Malasseziomycetes, Moniliellomycetes, Spiculogloeomycetes, Tritirachiomycetes and orders Amylocorticiales, Golubeviales, Holtermanniales, Jaapiales, Lepidostromatales, Robbauerales, Stereopsidales and Trichosporonales. However, the younger divergence times of Leucosporidiales (Microbotryomycetes) indicate that its order status is not supported, thus we propose combining it under Microbotryales. On the other hand, the families Buckleyzymaceae and Sakaguchiaceae (Cystobasidiomycetes) are raised to Buckleyzymales and Sakaguchiales due to their older divergence times. Cystofilobasidiales (Tremellomycetes) has an older divergence time and should be amended to a higher rank. We however, do not introduce it as new class here for Cystofilobasidiales, as DNA sequences from these taxa are not from their respective types and thus await further studies. Divergence times for Exobasidiomycetes, Cantharellales, Gomphales and Hysterangiales were obtained based on limited species sequences in molecular dating study. More comprehensive phylogenetic studies on those four taxa are needed in the future because our ML analysis based on wider sampling, shows they are not monophyletic groups. In general, the six-gene phylogenies are in agreement with the phyloproteomics tree except for the placements of Wallemiomycotina, orders Amylocorticiales, Auriculariales, Cantharellales, Geastrales, Sebacinales and Trechisporales from Agaricomycetes. These conflicting placements in the six-gene phylogeny vs the phyloproteomics tree are discussed. This leads to future perspectives for assessing gene orthology and problems in deciphering taxon ranks using divergence times.

Kuehneola japonica and K. warburgiana are the only species of genus Kuehneola that parasitize plants belonging to genus Rosa (Rosaceae). Systematic revision of the genus Phragmidium and related genera by molecular phylogenetic analyses using nuc rDNA internal transcribed spacer (5.8S-ITS2 = ITS2) and nuc rDNA 28S (28S) sequences indicated that K. japonica and K. warburgiana belong to a group of Phragmidium species that also occur on Rosa. Morphological and molecular phylogenetic analyses revealed that these Kuehneola species were transferred to Phragmidium and renamed as P. japonicum and P. warburgianum. Two new Phragmidium species were also discovered on Rosa from China that could be distinguished from other species in the genus based on aeciospore or urediniospore morphology and phylogenetic placement. The first species, P. jiangxiense, is characterized by a urediniospore surface structure with stout spines that are basally embedded in the wrinkled spore wall. The second species, P. leucoaecium, is characterized by an aeciospore surface structure with irregularly elongated verrucae. Taxonomic descriptions and illustrations are provided.

Resolving deep divergences in the tree of life is challenging even for analyses of genome-scale phylogenetic data sets. Relationships between Basidiomycota subphyla, the rusts and allies (Pucciniomycotina), smuts and allies (Ustilaginomycotina), and mushroom-forming fungi and allies (Agaricomycotina) were found particularly recalcitrant both to traditional multigene and genome-scale phylogenetics. Here, we address basal Basidiomycota relationships using concatenated and gene tree-based analyses of various phylogenomic data sets to examine the contribution of several potential sources of bias. We evaluate the contribution of biological causes (hard polytomy, incomplete lineage sorting) versus unmodeled evolutionary processes and factors that exacerbate their effects (e.g., fast-evolving sites and long-branch taxa) to inferences of basal Basidiomycota relationships. Bayesian Markov Chain Monte Carlo and likelihood mapping analyses reject the hard polytomy with confidence. In concatenated analyses, fast-evolving sites and oversimplified models of amino acid substitution favored the grouping of smuts with mushroom-forming fungi, often leading to maximal bootstrap support in both concatenation and coalescent analyses. On the contrary, the most conserved data subsets grouped rusts and allies with mushroom-forming fungi, although this relationship proved labile, sensitive to model choice, to different data subsets and to missing data. Excluding putative long-branch taxa, genes with high proportions of missing data and/or with strong signal failed to reveal a consistent trend toward one or the other topology, suggesting that additional sources of conflict are at play. While concatenated analyses yielded strong but conflicting support, individual gene trees mostly provided poor support for any resolution of rusts, smuts, and mushroom-forming fungi, suggesting that the true Basidiomycota tree might be in a part of tree space that is difficult to access using both concatenation and gene tree-based approaches. Inference-based assessments of absolute model fit strongly reject best-fit models for the vast majority of genes, indicating a poor fit of even the most commonly used models. While this is consistent with previous assessments of site-homogenous models of amino acid evolution, this does not appear to be the sole source of confounding signal. Our analyses suggest that topologies uniting smuts with mushroom-forming fungi can arise as a result of inappropriate modeling of amino acid sites that might be prone to systematic bias. We speculate that improved models of sequence evolution could shed more light on basal splits in the Basidiomycota, which, for now, remain unresolved despite the use of whole genome data.

Symmetrospora coprosmae is a red yeast from the subphylum Pucciniomycotina in the phylum Basidiomycota. Here, we present the first genome sequence of S. coprosmae strain UCD350, from an isolate collected from soil in Ireland. The genome size is 20.2 Mb.

Sixteen cold-adapted reddish-pigmented yeast strains were obtained from environmental samples. According to the PCR-based detection of classical yeast markers combined with phylogenetic studies, the yeasts belong mainly to the genera Rhodotorula, Sporobolomyces and Cystobasidium, all within the subphylum Pucciniomycotina. All strains produced carotenoids within a 0.25&ndash, 10.33 mg/L range under non-optimized conditions. Noteworthily, among them, representatives of the Cystobasidium genus were found, of particular value are the strains C. laryngis and C. psychroaquaticum, poorly described in the literature to date. Interestingly, carotenoid production with representatives of Cystobasidium was improved 1.8- to 10-fold at reduced temperature. As expected, most of the isolated yeasts biosynthesized extracellular lipases, but within them also one proteolytic and four cellulolytic strains were revealed. We succeeded in isolating strain Cystofilobasidium macerans WUT145 with extraordinarily high cellulolytic activity at 22&deg, C (66.23 &plusmn, 0.15 &micro, mol/mg protein&middot, min) that is described here for the first time. Consequently, a set of yeasts capable of producing both carotenoids and extracellular enzymes was identified. Taking into account those abilities, the strains might be applicable for a development of carotenoids production on an agro-industrial waste, e.g., lignocellulose.

The parsley hawthorn Crataegus marshallii Eggleston (Rosaceae, Maloideae) is a small tree native to the southeastern United States and is a less common but prized ornamental, known for its bright fruit and flaking bark. In March of 2020, a stem gall with visible aecia on the lower surface was observed on an ornamental parsley hawthorn in Gainesville, Alachua County, Florida, U.S.A. The affected stem was collected and brought to the Florida Department of Agriculture and Consumer Services – Division of Plant Industry headquarters in Gainesville for identification (FDACS-DPI, 2020-104160). Aecia tubular, whitish, occurred on twigs (caulicolous), producing terminal swellings, mostly short and up to 1.5 mm high with white peridium containing bright orange spores in masses. Aeciospores were semigloboid to globoid, with bright orange contents, 26 to 34 µm in diameter (n = 20)—color and size are considered diagnostic features (EPPO 2006)—wall was densely verrucose, hyaline, and 2 to 4 µm thick. The morphological characteristics are consistent with those of Gymnosporangium clavipes Cooke & Peck (Pucciniaceae, Pucciniomycotina) described by Kern (1973). A voucher was deposited in the Florida Department of Agriculture and Consumer Services DPI Herbarium (PIHG, specimen number 14893). The morphological identification was confirmed by molecular identification. Following DNA extraction, we performed PCR amplification and Sanger sequencing of the internal transcribed spacer (ITS) and the large subunit (LSU) (primer pairs ITS1/LR5, MW148514) of the rRNA genes (Aime 2006); phylogenetic analysis carried out in RAxMLv8.0.0 (Stamatakis 2014). Because of the inclination among Crataegus species to hybridize and the ornamental nature of the specimen, host identification was confirmed both morphologically and molecularly (ITS, primer pairs ITS1A/ITS4, MW148513, Lo et al. 2009) with 98 to 99% identity to C. marshallii sequences available in GenBank (MN215977, EF127037, EU683925), and it was placed within the other C. marshallii specimens in a broader phylogenetic estimate including sequence data from other available species of Crataegus (not shown). In agreement with the phylogenetic analysis, NCBI megaBLAST searches (Chen et al. 2015) of the resulting fungal sequences revealed 99% identity (ITS and LSU) to G. clavipes CUP-18207 (GenBank accession nos. MN605770, MN605692) and 99.65% identity (ITS and LSU, respectively; GenBank accession no. KT821552) against the strain of G. clavipes PUR N11552, first report of this rust occurring on another Rosaceae species, Pyrus calleryana Decaisne, in the United States (Creswell et al. 2016). Given the heteroecious and nonculturable nature of this pathogen, Koch’s postulates were not performed. This finding represents, to the best of our knowledge, the first record of G. clavipes in parsley hawthorn, and it adds to its broad range of known rosaceous hosts, having already been reported in 18 other species of Crataegus (Farr and Rossman 2020).

Early diverging taxa of Ascomycota and Basidiomycota share similarities in subcellular characters of the spindle pole body (SPB), nuclear division, and septal pore apparatus, but our understanding of character evolution is incomplete because of the limited number of structural studies within the earliest diverging subphyla of Dikarya, Taphrinomycotina and Pucciniomycotina. Two species of Helicogloea (Atractiellomycetes) were analyzed for these characters and provide data on SPB and nuclear division for an additional class of Pucciniomycotina. A detailed analysis of septal pore apparatus for the Helicogloea species permits comparisons with those of other Pucciniomycotina and Ascomycota. The endogenous origin of hyphal branches is shown to occur in a third class of Pucciniomycotina. The full set of characters supports a close relationship between Atractiellomycetes and Pucciniomycetes.

Among fungi isolated from healthy root mycobiomes of Populus, we discovered a new endorrhizal fungal species belonging to the rust lineage Pucciniomycotina, described here as Atractiella rhizophila. We characterized this species by transmission electron microscopy (TEM), phylogenetic analysis, and plant bioassay experiments. Phylogenetic sequence analysis of isolates and available environmental and reference sequences indicates that this new species, A. rhizophila, has a broad geographic and host range. Atractiella rhizophila appears to be present in North America, Australia, Asia, and Africa and is associated with trees, orchids, and other agriculturally important species, including soybean, corn, and rice. Despite the large geographic and host range of this species sampling, A. rhizophila appears to have exceptionally low sequence variation within nuclear rDNA markers examined. With inoculation studies, we demonstrate that A. rhizophila is nonpathogenic, asymptomatically colonizes plant roots, and appears to foster plant growth and elevated photosynthesis rates.

The genus Bannoa consists of four described species associated with dead leaves in southwestern Japan. In this study, we describe three new species, Bannoa guamensis, B. rosea, and B. tropicalis, from the South Pacific island of Guam and Guyana in South America. Isolates were obtained from surfaces of diseased and healthy leaves of plants in the Euphorbiaceae, Asteraceae, and Poaceae. DNA sequences from four gene regions, including nuc rDNA internal transcribed spacer ITS1‐5.8S‐ITS2 (ITS), D1–D2 domains of nuc 28S rDNA (28S), nuc 18S rDNA (18S), and a portion of tef1, which encodes translation elongation factor 1-alpha, were produced for phylogenetic analysis. Intercompatibility tests were performed, and subsequent development of clamp connections and basidia were documented for B. tropicalis. Potential life history strategies and association with diseased leaves, including rust-infected leaves, were evaluated across the genus. This is the first report of a species of Bannoa from South America.

Carotenoid-containing yeasts in Sporidiobolales (Microbotryomycetes, Pucciniomycotina, Basidiomycota) have been reported from contrasting ecosystems, including marine, soil, phylloplane, polar ice, and many others. Here, we present several analyses drawing on 583 new isolates collected from various substrates around the globe and publicly available sequences from numerous published environmental studies. We provide a multilocus phylogenetic reconstruction of the order, estimates for total species richness, a snapshot of global distribution patterns, and analysis of niche preferences in Sporidiobolales, emphasizing their occurrence in commercial crops and food products. We evaluated loci commonly used in fungal phylogenetics, finding that RNA polymerase II subunits 1 and 2 (RPB1, RPB2) are of little utility in this group. We have reconfirmed the monophyly of Sporidiobolales with three well-supported genera, which are, in descending order of number of species, Rhodotorula, Sporobolomyces, and Rhodosporidiobolus. From our data, we estimate ca. 260 species in Sporidiobolales, of which 42 are described, and ca. 52,000 species in Pucciniomycotina. The majority of data regarding Sporidiobolales are from North America and Europe, highlighting severe knowledge gaps for most of South and Central America and Africa.

With the change to one scientific name for pleomorphic fungi, generic names typified by sexual and asexual morphs have been evaluated to recommend which name to use when two names represent the same genus and thus compete for use. In this paper, generic names in Pucciniomycotina and Ustilaginomycotina are evaluated based on their type species to determine which names are synonyms. Twenty-one sets of sexually and asexually typified names in Pucciniomycotina and eight sets in Ustilaginomycotina were determined to be congeneric and compete for use. Recommendations are made as to which generic name to use. In most cases the principle of priority is followed. However, eight generic names in the Pucciniomycotina, and none in Ustilaginomycotina, are recommended for protection: Classicula over Naiadella, Gymnosporangium over Roestelia, Helicobasidium over Thanatophytum and Tuberculina, Melampsorella over Peridermium, Milesina over Milesia, Phragmidium over Aregma, Sporobolomyces over Blastoderma and Rhodomyces, and Uromyces over Uredo. In addition, eight new combinations are made: Blastospora juruensis, B. subneurophyla, Cronartium bethelii, C. kurilense, C. sahoanum, C. yamabense, Milesina polypodii, and Prospodium crusculum combs. nov. ISSN:2210-6340 ISSN:2210-6359

The orchid genus Teagueia Luer (Orchidaceae, subtribe Pleurothallidinae) presents an extraordinary example of recent local evolutionary radiation. In principle, mutualisms might affect the origin of plant species via an effect on speci- ation. As orchids depend on mycorrhizal fungi for seed ger- mination and early plantlet development we tested whether certain mycorrhizal fungi are acting as drivers of this radiation in Teagueia species. Sampling was carried out near Baños in east Andean Ecuador. Roots were collected from a total of 11 flowering individuals of eight morphospecies (referred to as Teagueia spp). The whole ITS1-5.8S- ITS2 nrDNA region and part of the 28S nrDNA were amplified, cloned and se- quenced. Molecular phylogeny of the obtained sequences re- vealed four phylogenetic species of Tulasnellaceae and one of Atractiellales (Pucciniomycotina, Basidiomycota) associated with Teagueia spp. Tulasnelloid fungi were detected in all samples. Up to three different phylogenetic species of mycobionts were found associated with one Teagueia species. We found that co-occurring Teagueia species share mycobionts. All detected mycobionts had wide geographical distribution. Based on the available evidence we conclude that the extraordinary local radiation of Teagueia is most likely driven by other factors than by mycorrhizal fungi, but that mycorrhiza may be a key factor for the coexistence of so many closely related orchid species.

Little is known about the biodiversity of marine yeast from New Zealand. Marine yeasts were isolated from various seaweed surfaces sampled at three locations in the Wellington Region. DNA sequencing of the internal transcribed spacer (ITS) regions was conducted, and the resultant sequence data were used in isolate identification. Yeasts isolated during this investigation were not unique; 71 isolates that are frequently detected in marine and terrestrial environments worldwide were identified from a range of seaweed genera. Furthermore, high ITS sequence similarity was observed between yeasts isolated during this investigation and those from geographically distant locations. These findings may indicate that marine yeasts are ubiquitous at a global level, although evidence is insufficient as to whether yeasts demonstrate biogeographic distribution patterns. Yeasts isolated during this investigation may have ecological implications in New Zealand's marine environment. Yeast isolates identified from s...

In most fungi, sexual reproduction is bipolar; that is, two alternate sets of genes at a single mating-type (MAT) locus determine two mating types. However, in the Basidiomycota, a unique (tetrapolar) reproductive system emerged in which sexual identity is governed by two unlinked MAT loci, each of which controls independent mechanisms of self/nonself recognition. Tetrapolar-to-bipolar transitions have occurred on multiple occasions in the Basidiomycota, resulting, for example, from linkage of the two MAT loci into a single inheritable unit. Nevertheless, owing to the scarcity of molecular data regarding tetrapolar systems in the earliest-branching lineage of the Basidiomycota (subphylum Pucciniomycotina), it is presently unclear if the last common ancestor was tetrapolar or bipolar. Here, we address this question, by investigating the mating system of the Pucciniomycotina yeast Leucosporidium scottii. Using whole-genome sequencing and chromoblot analysis, we discovered that sexual reproduction is governed by two physically unlinked gene clusters: a multiallelic homeodomain (HD) locus and a pheromone/receptor (P/R) locus that is biallelic, thereby dismissing the existence of a third P/R allele as proposed earlier. Allele distribution of both MAT genes in natural populations showed that the two loci were in strong linkage disequilibrium, but independent assortment of MAT alleles was observed in the meiotic progeny of a test cross. The sexual cycle produces fertile progeny with similar proportions of the four mating types, but approximately 2/3 of the progeny was found to be nonhaploid. Our study adds to others in reinforcing tetrapolarity as the ancestral state of all basidiomycetes.

The first records of Occultifur corticiorum, Spiculogloea occulta, S. subminuta (Pucciniomycotina), Phragmoxenidium mycophilum and Serendipita sigmaspora (Agaricomycotina) from Norway and Sweden are presented, and morphological characters and ecology of these species are discussed. In addition, Spiculogloea limonispora and S. minuta are reported as new to Russia, and Serendipita evanescens as new to USA.

Background Rhodotorula toruloides is an outstanding producer of lipids and carotenoids. Currently, information on the key metabolic pathways and their molecular basis of regulation remains scarce, severely limiting efforts to engineer it as an industrial host. Results We have adapted Agrobacterium tumefaciens-mediated transformation (ATMT) as a gene-tagging tool for the identification of novel genes in R. toruloides. Multiple factors affecting transformation efficiency in several species in the Pucciniomycotina subphylum were optimized. The Agrobacterium transfer DNA (T-DNA) showed predominantly single-copy chromosomal integrations in R. toruloides, which were trackable by high efficiency thermal asymmetric interlaced PCR (hiTAIL-PCR). To demonstrate the application of random T-DNA insertions for strain improvement and gene hunting, 3 T-DNA insertional libraries were screened against cerulenin, nile red and tetrazolium violet respectively, resulting in the identification of 22 mutants with obvious phenotypes in fatty acid or lipid metabolism. Similarly, 5 carotenoid biosynthetic mutants were obtained through visual screening of the transformants. To further validate the gene tagging strategy, one of the carotenoid production mutants, RAM5, was analyzed in detail. The mutant had a T-DNA inserted at the putative phytoene desaturase gene CAR1. Deletion of CAR1 by homologous recombination led to a phenotype similar to RAM5 and it could be genetically complemented by re-introduction of the wild-type CAR1 genome sequence. Conclusions T-DNA insertional mutagenesis is an efficient forward genetic tool for gene discovery in R. toruloides and related oleaginous yeast species. It is also valuable for metabolic engineering in these hosts. Further analysis of the 27 mutants identified in this study should augment our knowledge of the lipid and carotenoid biosynthesis, which may be exploited for oil and isoprenoid metabolic engineering. Electronic supplementary material The online version of this article (10.1186/s12866-018-1151-6) contains supplementary material, which is available to authorized users.

Stypella vermiformis is a heterobasidiomycete producing minute gelatinous basidiocarps on rotten wood of conifers in the Northern Hemisphere. In the current literature, Stypella papillata, the genus type of Stypella (described from Brazil), is treated as a taxonomic synonym of S. vermiformis. In the present paper, we revise the type material of S. papillata and a number of specimens addressed to S. vermiformis. As a result, the presumed synonymy of S. papillata and S. vermiformis is rejected and the genus Stypella is restricted to the single species S. papillata. Morphological and molecular phylogenetic studies of specimens from the Northern Hemisphere corresponding to the current concept of S. vermiformis uncovered three species from two newly described genera. S. vermiformis s.str. is distributed in temperate Europe and has small-sized basidia and basidiospores, and it is placed in a new genus, Mycostilla. Another genus, Stypellopsis, is created for two other species, the North American Stypellopsis farlowii, comb. nov., and the North European Stypellopsis hyperborea, sp. nov. Basidia and basidiospores of Stypellopsis spp. are larger than in Mycostilla vermiformis but other morphological characters are very similar. In addition, Spiculogloea minuta (Spiculogloeomycetes, Pucciniomycotina) is reported as new to Norway, parasitising basidiocarps of M. vermiformis and Tulasnella spp.

The taxonomy of the corticioid fungi from the class Atractiellomycetes (Pucciniomycotina, Basidiomycetes) currently addressed to the genus Helicogloea, is revised based on morphological and nuclear ribosomal DNA (ITS and LSU) data. The genus is restricted to 25 species with semitranslucent, gelatinous basidiocarps lacking differentiated cystidia and clamps on hyphae, of which 11 are described as new to science. The asexual genus Leucogloea is placed as a synonym of Helicogloea s. str. Since the type species of Saccoblastia, S. ovispora, is combined to Helicogloea, a new genus, Saccosoma, is introduced to encompass Saccoblastia farinacea and six related species, one of which is described as new. In contrast to Helicogloea in the strict sense, the basidiocarps of Saccosoma are arid, not gelatinized, and hyphae are clamped. The third lineage of the corticioid Atractiellomycetes is represented by the Bourdotigloea vestita complex. Species of Bourdotigloea are devoid of clamps but often possess well-differentiated cystidia, as well as long, cylindrical-fusiform basidiospores. Bourdotigloea encompasses nine species, of which six are described here as new. corticioid species phylogeny rust fungi taxonomy

Resolving deep divergences in the fungal tree of life remains a challenging task even for analyses of genome-scale phylogenetic datasets. Relationships between Basidiomycota subphyla, the rusts (Pucciniomycotina), smuts (Ustilaginomycotina) and mushroom forming fungi (Agaricomycotina) represent a particularly challenging situation that posed problems to both traditional multigene and genome-scale phylogenetic studies. Here, we address basal Basidiomycota relationships using three different phylogenomic datasets, concatenated and gene tree-based analyses and examine the contribution of several potential sources of uncertainty, including fast-evolving sites, putative long-branch taxa, model violation and missing data. We inferred conflicting results with different datasets and under different models. Fast-evolving sites and oversimplified models of amino acid substitution favored the grouping of smuts with mushroom-forming fungi, often leading to maximal bootstrap support in both concatenation and Astral analyses. The most conserved datasets grouped rusts with mushroom forming fungi, although this relationship proved labile, sensitive to model choice, different data subsets and missing data. Excluding putative long branch taxa, genes with the highest proportions of missing data and/or genes with strong signal failed to reveal a consistent trend toward one or the other topology, suggesting that additional sources of conflict are at play too. Our analyses suggest that topologies uniting smuts with mushroom forming fungi can arise as a result of inappropriate modeling of amino acid sites that might be prone to systematic bias. While concatenated analyses yielded strong but conflicting support, individual gene trees mostly provided poor support for rusts, smuts and mushroom-forming fungi, suggesting that the true Basidiomycota tree might be in a part of the tree space that is difficult to access using both concatenation and gene tree based approaches. Thus, basal Basidiomycota relationships remain unresolved and might represent a phylogenetic problem that remains contentious even in the genomic era.

Sterols, a class of lipids found in the cellular membranes of all eukaryotes, have vital roles in regulating membrane fluidity and permeability. While animal cells contain cholesterol in their membranes, plant cells contain phytosterols such as campesterol, sitosterol, and stigmasterol. The sterol ergosterol, discovered more than a century ago from the ergot fungus Claviceps purpurea [1], is a common component of many plant and human pathogenic fungi and is required for fungal growth. Fungal plant pathogens—in particular, the smut (Ustilaginomycotina subphyla) and the powdery mildew (Pezizomycotina subphyla) fungi—contain ergosterol in their membranes, while the rust fungi (Pucciniomycotina subphyla) synthesise slightly different forms of sterols [2]. In contrast to most pathogenic fungi, the oomycete pathogens from the order Peronosporales, such as Phytophthora and Pythium, are sterol auxotrophs. Therefore, these organisms acquire sterols externally, most likely from host membranes during pathogenesis [3].

Interactive identification keys for Australian smut fungi (Ustilaginomycotina and Pucciniomycotina, Microbotryales) and rust fungi (Pucciniomycotina, Pucciniales) are available online at http://collections.daff.qld.gov.au. The keys were built using Lucid software, and facilitate the identification of all known Australian smut fungi (317 species in 37 genera) and 100 rust fungi (from approximately 360 species in 37 genera). The smut and rust keys are illustrated with over 1,600 and 570 images respectively. The keys are designed to assist a wide range of end-users including mycologists, plant health diagnosticians, biosecurity scientists, plant pathologists, and university students. The keys are dynamic and will be regularly updated to include taxonomic changes and incorporate new detections, taxa, distributions and images. Researchers working with Australian smut and rust fungi are encouraged to participate in the on-going development and improvement of these keys.

An unusual fungus producing minute orange stilboid sporocarps was found on a palm leaf mid-rib in a Neotropical forest. Morphological observations could not place this collection into any previously described species or genus and, due to an absence of sexual structures, even higher level placement was uncertain. Phylogenetic analysis of a portion of the large subunit and the internal transcribed spacer of the nuclear ribosomal DNA indicated that this fungus is related to Heterogastridium pycnidioideum and belongs to Heterogastridiales, Microbotryomycetes (Pucciniomycotina). A new genus and species, Pycnopulvinus aurantiacus, are proposed here to accommodate this fungus.

Basidiomycota is one of the phyla of kingdom Fungi. This phylum contains besides non-pathogenic species and mushrooms, the important plant pathogens, smuts and rusts, and has been recently divided into three subphyla: Ustilaginomycotina, Pucciniomycotina, and Agaricomycotina (James et al. Nature 443:818-822, 2006; Hibbert et al. Mycological Research 111:509-547, 2007). Although the monophyletic origin of Basidiomycota appears practically undisputed, the phylogenetic relationships of the three subphyla have been considered somewhat uncertain (James et al. Nature 443:818-822, 2006). Previously, we described a hypothetical evolutionary scheme of the fungal cell wall (Ruiz-Herrera and Ortiz-Castellanos FEMS Yeast Research 10:225-243, 2010) that coincided with the accepted evolution tree of kingdom fungi (Cavalier-Smith Proceedings of the Royal Society of London B 271:1251-1262, 2004; James et al. Nature 443:818-822, 2006; Hibbert et al. Mycological Research 111:509-547, 2007). Based on the results of that study, we have now made an analysis of the phylogenetic relationships of the enzymes involved in the synthesis of the cell wall polysaccharides in Basidiomycota. According to our data, there is a close relationship of the wall-synthesizing enzymes with the accepted taxonomy of the group, with a few exceptions, noticeably the absence of chitin synthase IIb subclass in Pucciniomycotina, the duplication of chitin synthase class III in the same group, and the duplication of the gene encoding β-1,3-glucan synthase (Gls) in Agaricomycotina. These results give some clues on the evolution of the cell wall in Basidiomycota.

Microbotryum bistortum, M. dianthorum, M. superbum and M. langerheimii, rare species of smut fungi are reported from new localities in Poland, mostly in protected areas. Dianthus superbus subsp. superbus is a new host for M. superbum observed. Taxonomical status of M. carthusianorum and M. superbum is discussed in the paper.

Paratritirachium is a recently described, monotypic, basidiomycete genus in the Pucciniomycotina with one described asexual species, P. cylindroconium. Three strains of an undescribed species of Paratritirachium were isolated from flare pit soils from Alberta, Canada, using a heat treatment method. Both asexual and sexual propagules were produced in culture. Asexual reproduction was characterized by unbranched or sparingly branched conidiophores and sympodial, slightly vesicular conidiogenous cells producing aseptate conidia. Distinctive curved basidia were commonly produced in culture, yielding two pale brown, thick-walled and oval basidiospores. The basidiospores were heat-resistant and germinated only when exposed to heat. Phylogenetic analyses using the internal transcribed spacer (ITS) region and the combined small and large ribosomal subunits confirmed that these isolates are a new species of Paratritirachium, described in this study as P. curvibasidium, and that Paratritirachium should be classified in the class Tritirachiomycetes, order Tritirachiales, and family Tritirachiaceae. Transmission electron microscopy revealed simple, uniperforate septa, similar to those of a Tritirachium species, supporting the placement of Paratritirachium in the class Tritirachiomycetes. This study provides the first description of sexual reproduction in the Tritirachiomycetes and the first report of basidiospore germination after heat treatment at a high temperature (75 °C).

The yeasts that thrive in polar and subpolar areas have to be adapted to extreme environments with low temperatures and the consequential desiccation due to freezing of water into ice crystals, with relatively high concentrations of ions, generally low levels of nutrients and, sometimes, high UV irradiation and hypoxia. Yeast communities in polar areas include circumpolar, endemic and cosmopolitan species. Although some endemic yeast species show psychrophilic behaviour, the majority of them are psychrotolerant yeasts that can adapt to growth across a wide range of temperatures. Most investigations on yeasts in polar and subpolar areas have remained limited to their biodiversity and the quantification of rare or new species. Comparative taxonomic studies of polar and subpolar habitats from Antarctic, Arctic and sub-Arctic have shown that the yeast communities belong prevalently to Basidiomycota, in contrast to the general fungal community distribution, which shows Ascomycota as the dominant phylum. The reviews on yeast diversity in cold habitats worldwide that have been published in recent years have reported the unambiguous prevalence of the former basidiomycetous genera Cryptococcus and Rhodotorula. But the recent taxonomic revision of the Pucciniomycotina and Tremellomycetes taxa positioned these polyphyletic genera into many new taxa, thus modifying the known taxonomical picture and ecological significance of the yeast distribution in polar and subpolar ecosystems. To overcome the problems associated with the quantification of unculturable microbial communities, the new high-throughput sequencing of both DNA and RNA is proving to be a valuable tool in deciphering the microbial diversity in cold environments.

Rust fungi (Pucciniales) are the most speciose and the most complex group of plant pathogens. Historically, rust taxonomy was largely influenced by host and phenotypic characters, which are potentially plastic. Molecular systematic studies suggest that the extant diversity of this group was largely shaped by host jumps and subsequent shifts. However, it has been challenging to reconstruct the evolutionary history for the order, especially at deeper (family-level) nodes. Phylogenomics offer a potentially powerful tool to reconstruct the Pucciniales tree of life, although researchers working at this vanguard still face unprecedented challenges working with nonculturable organisms that possess some of the largest and most repetitive genomes now known in kingdom fungi. In this chapter, we provide an overview of the current status and special challenges of rust genomics, and we highlight how phylogenomics may provide new perspectives and answer long-standing questions regarding the biology of rust fungi.

A total of five strains were isolated from two different hybrid rice seeds samples (Oryza sativa L. Shenliangyou 5814 and Yliangyou 900) in Sanya city, Hainan province, China. Sequence analysis and physiological characteristics indicated that these strains were identical and represented a novel species. Molecular phylogenetic analysis of the D1/D2 domain of the large subunit rRNA gene and the internal transcribed spacer regions revealed that this new species is located in the Microsporomyces clade, with four closely related species, namely, M. magnisporus, M. orientalis, M. bloemfonteinensis, and M. pini. The novel species differed from these four described species in ability to assimilate sorbose, cellobiose, lactose, D-arabinose, and maltose. Based on these results, the following novel yeast species is proposed: Microsporomyces hainanensis sp. nov. with the type strain of Z8(T) (CICC 33066(T) = CBS 14092(T)) belongs to phylum Basidiomycota, subphylum Pucciniomycotina, class Cystobasidiomycetes, family Microsporomycetaceae. The new species were registered in MycoBank under MB 815471.