A monograph of Aspergillus section Candidi

Diaporthe species on palms - integrative taxonomic approach for species boundaries delimitation in the genus Diaporthe, with the description of D. pygmaeae sp. nov

The application of traditional morphological and ecological species concepts to closely related, asexual fungal taxa is challenging due to the lack of distinctive morphological characters and frequent cosmopolitan and plurivorous behaviour. As a result, multilocus sequence analysis (MLSA) has become a powerful and widely used tool to recognise and delimit independent evolutionary lineages (IEL) in fungi. However, MLSA can mask discordances in individual gene trees and lead to misinterpretation of speciation events. This phenomenon has been extensively documented in Diaporthe, and species identifications in this genus remains an ongoing challenge. However, the accurate delimitation of Diaporthe species is critical as the genus encompasses several cosmopolitan pathogens that cause serious diseases on many economically important plant hosts. In this regard, following a survey of palm leaf spotting fungi in Lisbon, Portugal, Diaporthe species occurring on Arecaceae hosts were used as a case study to implement an integrative taxonomic approach for a reliable species identification in the genus. Molecular analyses based on the genealogical concordance phylogenetic species recognition (GCPSR) and DNA-based species delimitation methods revealed that speciation events in the genus have been highly overestimated. Most IEL identified by the GCPSR were also recognised by Poisson tree processes (PTP) coalescent-based methods, which indicated that phylogenetic lineages in Diaporthe are likely influenced by incomplete lineage sorting (ILS) and reticulation events. Furthermore, the recognition of genetic recombination signals and the evaluation of genetic variability based on sequence polymorphisms reinforced these hypotheses. New clues towards the intraspecific variation in the common loci used for phylogenetic inference of Diaporthe species are discussed. These results demonstrate that intraspecific variability has often been used as an indicator to introduce new species in Diaporthe, which has led to a proliferation of species names in the genus. Based on these data, 53 species are reduced to synonymy with 18 existing Diaporthe species, and a new species, D. pygmaeae, is introduced. Thirteen new plant host-fungus associations are reported, all of which represent new host family records for Arecaceae. This study has recognised and resolved a total of 14 valid Diaporthe species associated with Arecaceae hosts worldwide, some of which are associated with disease symptoms. This illustrates the need for more systematic research to examine the complex of Diaporthe taxa associated with palms and determine their potential pathogenicity. By implementing a more rational framework for future studies on species delimitation in Diaporthe, this study provides a solid foundation to stabilise the taxonomy of species in the genus. Guidelines for species recognition, definition and identification in Diaporthe are included. Taxonomic novelties: New species: Diaporthe pygmaeae D.S. Pereira & A.J.L. Phillips. New synonyms: Diaporthe afzeliae Monkai & Lumyong, Diaporthe alangii C.M. Tian & Q. Yang, Diaporthe araliae-chinensis S.Y. Wang et al., Diaporthe australiana R.G. Shivas et al., Diaporthe australpacifica Y.P. Tan & R.G. Shivas, Diaporthe bombacis Monkai & Lumyong, Diaporthe caryae C.M. Tian & Q. Yang, Diaporthe chimonanthi (C.Q. Chang et al.) Y.H. Gao & L. Cai, Diaporthe conferta H. Dong et al., Diaporthe diospyrina Y.K. Bai & X.L. Fan, Diaporthe durionigena L.D. Thao et al., Diaporthe etinsideae Y.P. Tan & R.G. Shivas, Diaporthe eucalyptorum Crous & R.G. Shivas, Diaporthe fujianensis Jayaward. et al., Diaporthe fusiformis Jayaward. et al., Diaporthe globoostiolata Monkai & Lumyong, Diaporthe hainanensis Qin Yang, Diaporthe hongkongensis R.R. Gomes et al., Diaporthe hubeiensis Dissan. et al., Diaporthe infecunda R.R. Gomes et al., Diaporthe italiana Chethana et al., Diaporthe juglandigena S.Y. Wang et al., Diaporthe lagerstroemiae (C.Q. Chang et al.) Y.H. Gao & L. Cai, Diaporthe lithocarpi (Y.H. Gao et al.) Y.H. Gao & L. Cai, Diaporthe lutescens S.T. Huang et al., Diaporthe machili S.T. Huang et al., Diaporthe megabiguttulata M. Luo et al., Diaporthe middletonii R.G. Shivas et al., Diaporthe morindae M. Luo et al., Diaporthe nannuoshanensis S.T. Huang et al., Diaporthe nigra Brahman. & K.D. Hyde, Diaporthe orixae Q.T. Lu & Zhen Zhang, Diaporthe passifloricola Crous & M.J. Wingf., Diaporthe pimpinellae Abeywickrama et al., Diaporthe pseudoinconspicua T.G.L Oliveira et al., Diaporthe pungensis S.T. Huang et al., Diaporthe rhodomyrti C.M. Tian & Qin Yang, Diaporthe rosae M.C. Samar. & K.D. Hyde, Diaporthe rumicicola Manawas et al., Diaporthe salicicola R.G. Shivas et al., Diaporthe samaneae Monkai & Lumyong, Diaporthe subcylindrospora S.K. Huang et al., Diaporthe tectonae Doilom et al., Diaporthe tectonigena Doilom et al., Diaporthe theobromatis H. Dong et al., Diaporthe thunbergiicola Udayanga & K.D. Hyde, Diaporthe tuyouyouiae Y.P. Tan et al., Diaporthe unshiuensis F. Huang et al., Diaporthe vochysiae S.A. Noriler et al., Diaporthe xishuangbannaensis Hongsanan & K.D. Hyde, Diaporthe xylocarpi M.S. Calabon & E.B.G. Jones, Diaporthe zaobaisu Y.S. Guo & G.P. Wang, Diaporthe zhaoqingensis M. Luo et al. Citation: Pereira DS, Phillips AJL (2024). Diaporthe species on palms - integrative taxonomic approach for species boundaries delimitation in the genus Diaporthe, with the description of D. pygmaeae sp. nov. Studies in Mycology 109: 487-594. doi: 10.3114/sim.2024.109.08.

Biotechnological potential of salt tolerant and xerophilic species of Aspergillus

Xerophilic fungi occupy versatile environments owing to their rich arsenal helping them successfully adapt to water constraints as a result of low relative humidity, high-osmolarity, and high-salinity conditions. The general term xerophilic fungi relates to organisms that tolerate and/or require reduced water activity, while halophilic and osmophilic are applied to specialized groups that require high salt concentrations or increased osmotic pressure, respectively. Species belonging to the family Aspergillaceae, and especially those classified in Aspergillus subgenus Aspergillus (sections Restricti and Aspergillus) and Polypaecilum, are particularly enriched in the group of osmophilic and salt-tolerant filamentous fungi. They produce an unprecedently wide spectrum of salt tolerant enzymes including proteases, peptidases, glutaminases, γ-glutamyl transpeptidases, various glycosidases such as cellulose-decomposing and starch-degrading hydrolases, lipases, tannases, and oxidareductases. These extremophilic fungi also represent a huge untapped treasure chest of yet-to-be-discovered, highly valuable, biologically active secondary metabolites. Furthermore, these organisms are indispensable agents in decolorizing textile dyes, degrading xenobiotics and removing excess ions in high-salt environments. They could also play a role in fermentation processes at low water activity leading to the preparation of daqu, meju, and tea. Considering current and future agricultural applications, salt-tolerant and osmophilic Aspergilli may contribute to the biosolubilization of phosphate in soil and the amelioration salt stress in crops. Transgenes from halophile Aspergilli may find promising applications in the engineering of salt stress and drought-tolerant agricultural crops. Aspergilli may also spoil feed and food and raise mycotoxin concentrations above the permissible doses and, therefore, the development of novel feed and food preservation technologies against these Aspergillus spp. is also urgently needed. On the other hand, some xerophilic Aspergilli have been shown to be promising biological control agents against mites. KEY POINTS: • Salt tolerant and osmophilic Aspergilli can be found in versatile environments • These fungi are rich resources of valuable enzymes and secondary metabolites • Biotechnological and agricultural applications of these fungi are expanding.

Phylogenomics reveals extensive misidentification of fungal strains from the genus Aspergillus

Modern taxonomic classification is often based on phylogenetic analyses of a few molecular markers, although single-gene studies are still common. Here, we leverage genome-scale molecular phylogenetics (phylogenomics) of species and populations to reconstruct evolutionary relationships in a dense data set of 710 fungal genomes from the biomedically and technologically important genus Aspergillus. To do so, we generated a novel set of 1,362 high-quality molecular markers specific for Aspergillus and provided profile Hidden Markov Models for each, facilitating their use by others. Examining the resulting phylogeny helped resolve ongoing taxonomic controversies, identified new ones, and revealed extensive strain misidentification (7.59% of strains were previously misidentified), underscoring the importance of population-level sampling in species classification. These findings were corroborated using the current standard, taxonomically informative loci. These findings suggest that phylogenomics of species and populations can facilitate accurate taxonomic classifications and reconstructions of the Tree of Life.IMPORTANCEIdentification of fungal species relies on the use of molecular markers. Advances in genomic technologies have made it possible to sequence the genome of any fungal strain, making it possible to use genomic data for the accurate assignment of strains to fungal species (and for the discovery of new ones). We examined the usefulness and current limitations of genomic data using a large data set of 710 publicly available genomes from multiple strains and species of the biomedically, agriculturally, and industrially important genus Aspergillus. Our evolutionary genomic analyses revealed that nearly 8% of publicly available Aspergillus genomes are misidentified. Our work highlights the usefulness of genomic data for fungal systematic biology and suggests that systematic genome sequencing of multiple strains, including reference strains (e.g., type strains), of fungal species will be required to reduce misidentification errors in public databases.

Re-Identification of Aspergillus Subgenus Circumdati Strains in Korea Led to the Discovery of Three Unrecorded Species

Aspergillus is one of the largest and diverse genera of fungi with huge economical, biotechnological, and social significance. Taxonomically, Aspergillus is divided into six subgenera comprising 27 sections. In this study, 235 strains of Aspergillus subgenus Circumdati (section: Candidi, Circumdati, Flavi, Flavipedes, Nigri, and Terrei) preserved at the Korean Agricultural Culture Collection (KACC) were analyzed and re-identified using a combined dataset of partial β-tubulin (BenA), Calmodulin (CaM) gene sequences and morphological data. We confirmed nineteen species to be priorly reported in Korea (A. neotritici, A. terreus, A. floccosus, A. allahabadii, A. steynii, A. westerdijkiae, A. ochraceus, A. ostianus, A. sclerotiorum, A. luchuensis, A. tubingensis, A. niger, A. welwitschiae, A. japonicus, A. nomius, A. tamarii, A. parasiticus, A. flavi, and A. oryzae). Among the studied strains, three species (A. subalbidus, A. iizukae, and A. uvarum), previously unreported or not officially documented, were discovered in Korea, to the best of our knowledge. We have given a detailed description of the characteristic features of the three species, which remain uncharted in Korea.

Fungi involved in rhinosinusitis in arid regions: insights from molecular identification and antifungal susceptibility

Fungal rhinosinusitis (FRS) is a common problem worldwide, with an increasing burden in arid climate regions. Aspergillus species are the most common causative agents involved. In the present study, we investigated the prevalence, molecular characterization, and antifungal susceptibility of opportunists causing FRS in Sudan on the basis of strains collected over a period of 5 years. β-Tubulin and calmodulin sequencing were used for species identification, and antifungal susceptibility profiles were evaluated by the protocol of the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Predominant species belonged to the Aspergillus flavus complex (n = 244), A. terreus complex (n = 16), A. fumigatus complex (n = 7), and other fungi (n = 17). Molecular identification of 94 strains of Aspergillus revealed the following species: A. flavus (n = 88), A. terreus (n = 1), A. citrinoterreus (n = 2), A. fumigatus (n = 1), A. caespitosus (n = 1), and A. sydowii (n = 1). Several A. flavus and an A. fumigatus isolates showed reduced susceptibility to azoles (minimum inhibitory concentrations above the clinical breakpoints or epidemiological cutoff values). Despite several mutations revealed in cyp51A of these isolates, none could be directly linked to azole resistance. Molecular identification of fungi causing FRS is useful to identify cryptic species and for epidemiologic studies. IMPORTANCE Fungal rhinosinusitis (FRS) is a significant clinical problem in arid regions. This study provides new insights into the prevalence, etiology, and antifungal susceptibility of FRS pathogens in Sudan, where the disease burden is high. Aspergillus species, particularly the A. flavus complex, were identified as the primary FRS pathogens in the region, with some evidence of antifungal resistance. The molecular identification of fungal species causing FRS is useful for detecting antifungal resistance, identifying cryptic species, and characterizing the epidemiology of the disease. The emergence of Azole resistance Aspergilli in Sudan highlights the need for continued surveillance and appropriate use of antifungal agents. These findings have important implications for clinical management, public health policy, and future research on FRS. Publishing this study in Microbiology Spectrum would enable other researchers and clinicians to build on these findings, ultimately improving the diagnosis, treatment, and prevention of FRS.

Seven New Species of Eurotiales (Ascomycota) Isolated from Tidal Flat Sediments in China

Tidal flats have been reported to contain many microorganisms and play a critical role in maintaining biodiversity. In surveys of filamentous fungi from tidal flat sediments in China, seven new species of Eurotiales were discovered and described. Morphological characteristics and DNA sequence analyses of combined datasets of the BenA, CaM, and RPB2 regions support their placements and recognition as new species. Aspergillus liaoningensis sp. nov. and A. plumeriae sp. nov. belong to sections Candidi and Flavipedes of subgenus Circumdati, and A. subinflatus sp. nov. is a member of section Cremei of subgenus Cremei. Penicillium danzhouense sp. nov., P. tenue sp. nov., and P. zhanjiangense sp. nov. are attributed to sections Exilicaulis and Lanata-Divaricata of subgenus Aspergilloides. Talaromyces virens sp. nov. is in section Talaromyces. Detailed descriptions and illustrations of these novel taxa are provided. Their differences from close relatives were compared and discussed.

OMICS and Other Advanced Technologies in Mycological Applications

Fungi play many roles in different ecosystems. The precise identification of fungi is important in different aspects. Historically, they were identified based on morphological characteristics, but technological advancements such as polymerase chain reaction (PCR) and DNA sequencing now enable more accurate identification and taxonomy, and higher-level classifications. However, some species, referred to as "dark taxa", lack distinct physical features that makes their identification challenging. High-throughput sequencing and metagenomics of environmental samples provide a solution to identifying new lineages of fungi. This paper discusses different approaches to taxonomy, including PCR amplification and sequencing of rDNA, multi-loci phylogenetic analyses, and the importance of various omics (large-scale molecular) techniques for understanding fungal applications. The use of proteomics, transcriptomics, metatranscriptomics, metabolomics, and interactomics provides a comprehensive understanding of fungi. These advanced technologies are critical for expanding the knowledge of the Kingdom of Fungi, including its impact on food safety and security, edible mushrooms foodomics, fungal secondary metabolites, mycotoxin-producing fungi, and biomedical and therapeutic applications, including antifungal drugs and drug resistance, and fungal omics data for novel drug development. The paper also highlights the importance of exploring fungi from extreme environments and understudied areas to identify novel lineages in the fungal dark taxa.

Consolidation of Chloridium: new classification into eight sections with 37 species and reinstatement of the genera Gongromeriza and Psilobotrys

Chloridium is a little-studied group of soil- and wood-inhabiting dematiaceous hyphomycetes that share a rare mode of phialidic conidiogenesis on multiple loci. The genus has historically been divided into three morphological sections, i.e. Chloridium, Gongromeriza, and Psilobotrys. Sexual morphs have been placed in the widely perceived genus Chaetosphaeria, but unlike their asexual counterparts, they show little or no morphological variation. Recent molecular studies have expanded the generic concept to include species defined by a new set of morphological characters, such as the collar-like hyphae, setae, discrete phialides, and penicillately branched conidiophores. The study is based on the consilience of molecular species delimitation methods, phylogenetic analyses, ancestral state reconstruction, morphological hypotheses, and global biogeographic analyses. The multilocus phylogeny demonstrated that the classic concept of Chloridium is polyphyletic, and the original sections are not congeneric. Therefore, we abolish the existing classification and propose to restore the generic status of Gongromeriza and Psilobotrys. We present a new generic concept and define Chloridium as a monophyletic, polythetic genus comprising 37 species distributed in eight sections. In addition, of the taxa earlier referred to Gongromeriza, two have been redisposed to the new genus Gongromerizella. Analysis of published metabarcoding data showed that Chloridium is a common soil fungus representing a significant (0.3 %) proportion of sequence reads in environmental samples deposited in the GlobalFungi database. The analysis also showed that they are typically associated with forest habitats, and their distribution is strongly influenced by climate, which is confirmed by our data on their ability to grow at different temperatures. We demonstrated that Chloridium forms species-specific ranges of distribution, which is rarely documented for microscopic soil fungi. Our study shows the feasibility of using the GlobalFungi database to study the biogeography and ecology of fungi. Taxonomic novelties: New genus: Gongromerizella Réblová; New sections: Chloridium section Cryptogonytrichum Réblová, Hern.-Restr., M. Kolařík & F. Sklenar, Chloridium section Gonytrichopsis Réblová, Hern.-Restr., M. Kolařík & F. Sklenar, Chloridium section Metachloridium Réblová, Hern.-Restr., M. Kolařík & F. Sklenar, Chloridium section Volubilia Réblová, Hern.-Restr., M. Kolařík & F. Sklenar; New species: Chloridium bellum Réblová & Hern.-Restr., Chloridium biforme Réblová & Hern.-Restr., Chloridium detriticola Réblová & Hern.-Restr., Chloridium gamsii Réblová & Hern.-Restr., Chloridium guttiferum Réblová & Hern.-Restr., Chloridium moratum Réblová & Hern.-Restr., Chloridium peruense Réblová & Hern.-Restr., Chloridium novae-zelandiae Réblová & Hern.-Restr., Chloridium elongatum Réblová & Hern.-Restr., Chloridium volubile Réblová & Hern.-Restr.; New varieties: Chloridium bellum var. luteum Réblová & Hern.-Restr., Chloridium detriticola var. effusum Réblová & Hern.-Restr., Chloridium chloridioides var. convolutum Réblová & Hern.-Restr.; New combinations: Chloridium section Gonytrichum (Nees & T. Nees) Réblová, Hern.-Restr., M. Kolařík & F. Sklenar, Chloridium section Mesobotrys (Sacc.) Réblová, Hern.-Restr., M. Kolařík & F. Sklenar, Chloridium section Pseudophialocephala (M.S. Calabon et al.) Réblová, Hern.-Restr., M. Kolařík & F. Sklenar, Chloridium simile (W. Gams & Hol.-Jech.) Réblová & Hern.-Restr., Chloridium chloridioides (W. Gams & Hol.-Jech.) Réblová & Hern.-Restr., Chloridium subglobosum (W. Gams & Hol.-Jech.) Réblová & Hern.-Restr., Chloridium fuscum (Corda) Réblová & Hern.-Restr., Chloridium ypsilosporum (Hol.-Jech.) Réblová & Hern.-Restr., Chloridium costaricense (G. Weber et al.) Réblová & Hern.-Restr., Chloridium cuneatum (N.G. Liu et al.) Réblová & Hern.-Restr., Fusichloridium cylindrosporum (W. Gams & Hol.-Jech.) Réblová, Gongromeriza myriocarpa (Fr.) Réblová, Gongromeriza pygmaea (P. Karst.) Réblová, Gongromerizella lignicola (F. Mangenot) Réblová, Gongromerizella pachytrachela (W. Gams & Hol.-Jech) Réblová, Gongromerizella pini (Crous & Akulov) Réblová; New name: Chloridium pellucidum Réblová & Hern.-Restr.; Epitypifications (basionyms): Chaetopsis fusca Corda, Gonytrichum caesium var. subglobosum W. Gams & Hol.-Jech.; Lectotypification (basionym): Gonytrichum caesium Nees & T. Nees. Citation: Réblová M, Hernández-Restrepo M, Sklenář F, Nekvindová J, Réblová K, Kolařík M (2022). Consolidation of Chloridium: new classification into eight sections with 37 species and reinstatement of the genera Gongromeriza and Psilobotrys. Studies in Mycology 103: 87-212. doi: 10.3114/sim.2022.103.04.