An online resource for marine fungi

Colonization and Biodegradation Potential of Fungal Communities on Immersed Polystyrene vs. Biodegradable Plastics: A Time Series Study in a Marina Environment

Plastic pollution of the ocean is a major environmental threat. In this context, a better understanding of the microorganisms able to colonize and potentially degrade these pollutants is of interest. This study explores the colonization and biodegradation potential of fungal communities on foamed polystyrene and alternatives biodegradable plastics immersed in a marina environment over time, using the Brest marina (France) as a model site. The methodology involved a combination of high-throughput 18S rRNA gene amplicon sequencing to investigate fungal taxa associated with plastics compared to the surrounding seawater, and a culture-dependent approach to isolate environmentally relevant fungi to further assess their capabilities to utilize polymers as carbon sources. Metabarcoding results highlighted the significant diversity of fungal communities associated with both foamed polystyrene and biodegradable plastics, revealing a dynamic colonization process influenced by the type of polymer and immersion time. Notably, the research suggests a potential for certain fungal species to utilize polymers as a carbon source, emphasizing the need for further exploration of fungal biodegradation potential and mechanisms.

An overview of Melanommataceae (Pleosporales, Dothideomycetes): Current insight into the host associations and geographical distribution with some interesting novel additions from plant litter

Melanommataceous species exhibit high diversity with a cosmopolitan distribution worldwide and show a prominent saprobic lifestyle. In this study, we explored five saprobic species collected from plant litter substrates from terrestrial habitats in China and Thailand. A combination of morphological characteristics and multi-locus phylogenetic analyses was used to determine their taxonomic classifications. Maximum Likelihood and Bayesian Inference analyses of combined LSU, SSU, ITS and tef1-α sequence data were used to clarify the phylogenetic affinities of the species. Byssosphaeriapoaceicola and Herpotrichiazingiberacearum are introduced as new species, while three new host records, Bertiellafici, By.siamensis and Melanommapopulicola are also reported from litter of Cinnamomumverum, Citrustrifoliata and Fagussylvatica, respectively. Yet, despite the rising interest in the melanommataceous species, there is a considerable gap in knowledge on their host associations and geographical distributions. Consequently, we compiled the host-species associations and geographical distributions of all the so far known melanommataceous species.

Loggerhead Sea Turtles as Hosts of Diverse Bacterial and Fungal Communities

Research on microbial communities associated with wild animals provides a valuable reservoir of knowledge that could be used for enhancing their rehabilitation and conservation. The loggerhead sea turtle (Caretta caretta) is a globally distributed species with its Mediterranean population categorized as least concern according to the IUCN Red List of Threatened Species as a result of robust conservation efforts. In our study, we aimed to further understand their biology in relation to their associated microorganisms. We investigated epi- and endozoic bacterial and endozoic fungal communities of cloaca, oral mucosa, carapace biofilm. Samples obtained from 18 juvenile, subadult, and adult turtles as well as 8 respective enclosures, over a 3-year period, were analysed by amplicon sequencing of 16S rRNA gene and ITS2 region of nuclear ribosomal gene. Our results reveal a trend of decreasing diversity of distal gut bacterial communities with the age of turtles. Notably, Tenacibaculum species show higher relative abundance in juveniles than in adults. Differential abundances of taxa identified as Tenacibaculum, Moraxellaceae, Cardiobacteriaceae, and Campylobacter were observed in both cloacal and oral samples in addition to having distinct microbial compositions with Halioglobus taxa present only in oral samples. Fungal communities in loggerheads' cloaca were diverse and varied significantly among individuals, differing from those of tank water. Our findings expand the known microbial diversity repertoire of loggerhead turtles, highlighting interesting taxa specific to individual body sites. This study provides a comprehensive view of the loggerhead sea turtle bacterial microbiota and marks the first report of distal gut fungal communities that contributes to establishing a baseline understanding of loggerhead sea turtle holobiont.

Marine Fungal Diversity and Dynamics in the Gulf of Trieste (Northern Adriatic Sea)

Fungi contribute to different important ecological processes, including decomposition of organic matter and nutrient cycling, but in the marine environment the main factors influencing their diversity and dynamics at the spatial and temporal levels are still largely unclear. In this study, we performed DNA metabarcoding on seawater sampled monthly over a year and a half in the Gulf of Trieste (northern Adriatic Sea), targeting the internal transcribed spacer (ITS) and the 18S rRNA gene regions. The fungal communities were diverse, very dynamic, and belonged predominantly to marine taxa. Samples could be clustered in two groups, mainly based on the high (> 30%) or low relative proportion of the ascomycetes Parengyodontium album, which emerged as a key taxon in this area. Dissolved and particulate organic C:N ratio played important roles in shaping the mycoplankton assemblages, suggesting that differently bioavailable organic matter pools may be utilized by different consortia. The proportion of fungal over total reads was 31% for ITS and 0.7% for 18S. ITS had the highest taxonomic resolution but low power to detect early divergent fungal lineages. Our results on composition, distribution, and environmental drivers extended our knowledge of the structure and function of the mycobiome of coastal waters.

Sunken Riches: Ascomycete Diversity in the Western Mediterranean Coast through Direct Plating and Flocculation, and Description of Four New Taxa

The Mediterranean Sea stands out as a hotspot of biodiversity, whose fungal composition remains underexplored. Marine sediments represent the most diverse substrate; however, the challenge of recovering fungi in culture hinders the precise identification of this diversity. Concentration techniques like skimmed milk flocculation (SMF) could represent a suitable solution. Here, we compare the effectiveness in recovering filamentous ascomycetes of direct plating and SMF in combination with three culture media and two incubation temperatures, and we describe the fungal diversity detected in marine sediments. Sediments were collected at different depths on two beaches (Miracle and Arrabassada) on the Spanish western Mediterranean coast between 2021 and 2022. We recovered 362 strains, and after a morphological selection, 188 were identified primarily with the LSU and ITS barcodes, representing 54 genera and 94 species. Aspergillus, Penicillium, and Scedosporium were the most common genera, with different percentages of abundance between both beaches. Arrabassada Beach was more heterogeneous, with 42 genera representing 60 species (Miracle Beach, 28 genera and 54 species). Although most species were recovered with direct plating (70 species), 20 species were exclusively obtained using SMF as a sample pre-treatment, improving our ability to detect fungi in culture. In addition, we propose three new species in the genera Exophiala, Nigrocephalum, and Queenslandipenidiella, and a fourth representing the novel genus Schizochlamydosporiella. We concluded that SMF is a useful technique that, in combination with direct plating, including different culture media and incubation temperatures, improves the chance of recovering marine fungal communities in culture-dependent studies.

Family matters inside the order Agaricales: systematic reorganization and classification of incertae sedis clitocyboid, pleurotoid and tricholomatoid taxa based on an updated 6-gene phylogeny

The phylogenetic position of several clitocyboid/pleurotoid/tricholomatoid genera previously considered incertae sedis is here resolved using an updated 6-gene dataset of Agaricales including newly sequenced lineages and more complete data from those already analyzed before. Results allowed to infer new phylogenetic relationships, and propose taxonomic novelties to accommodate them, including up to ten new families and a new suborder. Giacomia (for which a new species from China is here described) forms a monophyletic clade with Melanoleuca (Melanoleucaceae) nested inside suborder Pluteineae, together with the families Pluteaceae, Amanitaceae (including Leucocortinarius), Limnoperdaceae and Volvariellaceae. The recently described family Asproinocybaceae is shown to be a later synonym of Lyophyllaceae (which includes also Omphaliaster and Trichocybe) within suborder Tricholomatineae. The families Biannulariaceae, Callistosporiaceae, Clitocybaceae, Fayodiaceae, Macrocystidiaceae (which includes Pseudoclitopilus), Entolomataceae, Pseudoclitocybaceae (which includes Aspropaxillus), Omphalinaceae (Infundibulicybe and Omphalina) and the new families Paralepistaceae and Pseudoomphalinaceae belong also to Tricholomatineae. The delimitation of the suborder Pleurotineae (= Schizophyllineae) is discussed and revised, accepting five distinct families within it, viz. Pleurotaceae, Cyphellopsidaceae, Fistulinaceae, Resupinataceae and Schizophyllaceae. The recently proposed suborder Phyllotopsidineae (= Sarcomyxineae) is found to encompass the families Aphroditeolaceae, Pterulaceae, Phyllotopsidaceae, Radulomycetaceae, Sarcomyxaceae (which includes Tectella), and Stephanosporaceae, all of them unrelated to Pleurotaceae (suborder Pleurotineae) or Typhulaceae (suborder Typhulineae). The new family Xeromphalinaceae, encompassing the genera Xeromphalina and Heimiomyces, is proposed within Marasmiineae. The suborder Hygrophorineae is here reorganized into the families Hygrophoraceae, Cantharellulaceae, Cuphophyllaceae, Hygrocybaceae and Lichenomphaliaceae, to homogenize the taxonomic rank of the main clades inside all suborders of Agaricales. Finally, the genus Hygrophorocybe is shown to represent a distinct clade inside Cuphophyllaceae, and the new combination H. carolinensis is proposed. Taxonomic novelties: New suborder: Typhulineae Vizzini, Consiglio & P. Alvarado. New families: Aphroditeolaceae Vizzini, Consiglio & P. Alvarado, Melanoleucaceae Locq. ex Vizzini, Consiglio & P. Alvarado, Paralepistaceae Vizzini, Consiglio & P. Alvarado, Pseudoomphalinaceae Vizzini, Consiglio & P. Alvarado, Volvariellaceae Vizzini, Consiglio & P. Alvarado, Xeromphalinaceae Vizzini, Consiglio & P. Alvarado. New species: Giacomia sinensis J.Z. Xu. Stat. nov.: Cantharellulaceae (Lodge, Redhead, Norvell & Desjardin) Vizzini, Consiglio & P. Alvarado, Cuphophyllaceae (Z.M. He & Zhu L. Yang) Vizzini, Consiglio & P. Alvarado, Hygrocybaceae (Padamsee & Lodge) Vizzini, Consiglio & P. Alvarado, Lichenomphaliaceae (Lücking & Redhead) Vizzini, Consiglio & P. Alvarado. New combination: Hygrophorocybe carolinensis (H.E. Bigelow & Hesler) Vizzini, Consiglio & P. Alvarado. New synonyms: Sarcomyxineae Zhu L. Yang & G.S. Wang, Schizophyllineae Aime, Dentinger & Gaya, Asproinocybaceae T. Bau & G.F. Mou. Incertae sedis taxa placed at family level: Aphroditeola Redhead & Manfr. Binder, Giacomia Vizzini & Contu, Hygrophorocybe Vizzini & Contu, Leucocortinarius (J.E. Lange) Singer, Omphaliaster Lamoure, Pseudoclitopilus Vizzini & Contu, Resupinatus Nees ex Gray, Tectella Earle, Trichocybe Vizzini. New delimitations of taxa: Hygrophorineae Aime, Dentinger & Gaya, Phyllotopsidineae Zhu L. Yang & G.S. Wang, Pleurotineae Aime, Dentinger & Gaya, Pluteineae Aime, Dentinger & Gaya, Tricholomatineae Aime, Dentinger & Gaya. Resurrected taxa: Fayodiaceae Jülich, Resupinataceae Jülich. Citation: Vizzini A, Alvarado P, Consiglio G, Marchetti M, Xu J (2024). Family matters inside the order Agaricales: systematic reorganization and classification of incertae sedis clitocyboid, pleurotoid and tricholomatoid taxa based on an updated 6-gene phylogeny. Studies in Mycology 107: 67-148. doi: 10.3114/sim.2024.107.02.

Rambellisea gigliensis and Rambellisea halocynthiae, gen. et spp. nov. (Lulworthiaceae) from the Marine Tunicate Halocynthia papillosa

In this study, 15 Lulworthiales strains isolated from the marine tunicate Halocynthia papillosa collected in the central Tyrrhenian Sea were characterized using a polyphasic approach (morpho-physiological, molecular, and phylogenetic analyses). Based on multi-locus phylogenetic inference and morphological characters, a new genus, Rambellisea, and two new species, R. halocynthiae and R. gigliensis (Lulworthiales), were proposed. Multi-locus phylogenetic analyses using the nuclear ribosomal regions of DNA (nrITS1-nr5.8S-nrITS2, nrLSU, and nrSSU) sequence data strongly supported the new taxa. Phylogenetic inference, estimated using Maximum Likelihood and Bayesian Inference, clearly indicates that Rambellisea gen. nov. forms a distinct clade within the order Lulworthiales. Moreover, the two new species were separated into distinct subclades, solidly supported by the analyses. This is the first report of Lulworthiales species isolated from animals.

Why Are There So Few Basidiomycota and Basal Fungi as Endophytes? A Review

A review of selected studies on fungal endophytes confirms the paucity of Basidiomycota and basal fungi, with almost 90% attributed to Ascomycota. Reasons for the low number of Basidiomycota and basal fungi, including the Chytridiomycota, Mucoromycota, and Mortierellomycota, are advanced, including isolation procedure and media, incubation period and the slow growth of basidiomycetes, the identification of non-sporulating isolates, endophyte competition, and fungus-host interactions. We compare the detection of endophytes through culture-dependent methods and culture-independent methods, the role of fungi on senescence of the host plant, and next-generation studies.

Microascaceae from the Marine Environment, with Descriptions of Six New Species

Most reported members of Microascaceae that have been reported originate from the terrestrial environment, where they act as saprobes or plant pathogens. However, our understanding of their species diversity and distribution in the marine environment remains vastly limited, with only 22 species in nine genera having been reported so far. A survey of the fungal diversity in intertidal areas of China's mainland has revealed the discovery of several Microascaceae strains from 14 marine algae and 15 sediment samples. Based on morphological characteristics and LSU-ITS-tef1-tub2 multilocus phylogeny using Bayesian inference and maximum likelihood methods, 48 strains were identified as 18 species belonging to six genera. Among these, six new species were discovered: Gamsia sedimenticola, Microascus algicola, M. gennadii, Scedosporium ellipsosporium, S. shenzhenensis, and S. sphaerospermum. Additionally, the worldwide distribution of the species within this family across various marine habitats was briefly reviewed and discussed. Our study expands the knowledge of species diversity and distribution of Microascaceae in the marine environment.

Taxonomic and life cycle reappraisals of the marine basidiomycete Nia vibrissa complex, with descriptions of three new Nia species

The marine basidiomycete Nia vibrissa has been regarded as a species complex, possibly including several species, because morphological variations in fruitbody, spore, and spore appendage have been observed in materials from worldwide collections. Using more than 50 monosporic isolates of N. vibrissa-like fungi mainly obtained from Japanese beach coasts, we investigated their molecular phylogeny, morphological characteristics, mating compatibility, nuclear behavior during spore formation, and life cycles. Molecular phylogenetic analyses separated the examined strains into seven clades. Each clade of fungi exhibited distinctive characteristics in fruitbodies and spores produced by culturing monokaryotic strains and mated dikaryotic strains; these characteristics included the color of fruitbodies, apical structure of peridial hair hyphae, spore shape, and apical structure of spore appendages. Mating tests of monokaryotic strains demonstrated mating compatibility between strains within a clade and incompatibility among clades. Therefore, each clade of fungi was phylogenetically, morphologically, and biologically recognized as a different Nia species. Observation of the type specimen of N. vibrissa revealed a tiny T-shaped apical structure of spore appendages-not mentioned in the original description-that is unique to the species. This finding, together with the original description, suggests that our studied strains include N. aff. vibrissa, whose morphology is mostly identical to N. vibrissa sensu stricto, and three new species. Thus, we describe three new Nia species and propose emendation of the descriptions of the genus Nia. Culture-based studies have demonstrated that Nia species have both sexual and asexual morphs that produce morphologically similar fruitbodies (basidiomata and conidiomata) and spores (basidiospores and conidia). Because it has both morphs forming appendaged waterborne basidiospores and conidia, Nia must be the most well-adapted marine basidiomycete, ensuring the continuation of new generations by two morphs, while distributing in and inhabiting numerous marine environments.

Mushrooms Adapted to Seawater: Two New Species of Candolleomyces (Basidiomycota, Agaricales) from China

Marine fungi have been studied for a long history in many realms, but there are few reports on marine mushrooms. In this study, marine fungi with conspicuous subglobose sequestrate basidioma were discovered from mangrove forests in South China. They grow on the deadwood of mangroves in the intertidal zone, periodically submerging into seawater due to the tide. Some marine animals were observed to nest in their basidiomata or consume them as food. The pileus-gleba-inner veil complex (PGI) of the basidioma was observed to be detached from the stipe and transferred into seawater by external forces, and drifting on sea to spread spores after maturity. The detachment mechanism of their PGIs was revealed through detailed microscopic observations. The contrast culturing experiment using freshwater and seawater potato dextrose agar media showed they have probably obligately adapted to the marine environment. Based on morphological and molecular phylogenetic evidence, two new species of Candolleomyces (Basidiomycota, Agaricales), namely C. brunneovagabundus and C. albovagabundus, were described. They are similar and close to each other, but can be distinguished by the size and color of the basidioma, and the size of the basidiospores.

Shotgun metagenomics reveals a diverse mycobiome in the seawater from a High Arctic fjord (Kongsfjorden, Svalbard)

In the Arctic fjords, the marine mycobiome experiences significant changes under environmental conditions driven by climate change. However, research on the ecological roles and the adaptive mechanisms of marine mycobiome in the Arctic fjord remains insufficiently explored. The present study employed shotgun metagenomics to comprehensively characterize the mycobiome in 24 seawater samples from Kongsfjorden, a High Arctic fjord situated in Svalbard. It revealed the presence of a diverse mycobiome with eight phyla, 34 classes, 71 orders, 152 families, 214 genera, and 293 species. The taxonomic and functional composition of the mycobiome differed significantly among the three layers, i.e., upper layer (depth of 0 m), middle layer (depths of 30-100 m), and lower layer (depths of 150-200 m). Several taxonomic groups (e.g., phylum Ascomycota, class Eurotiomycetes, order Eurotiales, family Aspergillaceae, and genus Aspergillus) and KOs (e.g., K03236/EIF1A, K03306/TC.PIT, K08852/ERN1, and K03119/tauD) were significantly distinct among the three layers. Among the measured environmental parameters, depth, NO2-, and PO43- were identified as the key factors influencing the mycobiome composition. Conclusively, our findings revealed that the mycobiome was diverse in the Arctic seawater and significantly impacted by the variability of environmental conditions in the High Arctic fjord. These results will assist future studies in exploring the ecological and adaptive responses towards the changes within the Arctic ecosystems.

Redefining the Genus Corollospora Based on Morphological and Phylogenetic Approaches

The present study, initially to resolve the cryptic species within Corollospora maritima, is to determine how to attain taxonomic discrimination at species and generic levels. Multiple sequence alignments (MSAs) of the ITS, 28S, and 18S regions of the nuclear ribosomal cistron were separately subjected to pairwise distance assessments, Bayesian, and Maximum likelihood phylogenetic analyses. Morphological descriptions of 15 type strains of Corollospora species, along with MSAs involving representatives of the whole genus Corollospora (268 isolates, many from C. maritima sensu lato) totaling 355 published sequences, allowed phylogenetic assessments conducted to the following p-distance thresholds in the ITS/28S regions: ≥3%/1% for species segregation and ≥8%/2% for generic segregation. This resulted in the introduction of 10 new genera encompassing 13 new combinations of current Corollospora species: Ajigaurospora pseudopulchella, Corollosporella anglusa, Corollosporella ramulosa, Corollosporopsis portsaidica, Garethelia parvula, Honshuriella fusca, Keraliethelia pulcehlla, Nakagariella filiformis, Paracorollospora angusta, Paracorollospora luteola, Paracorollospora marina, Shirahamella gracilis, and Tokuratelia colossa. Furthermore, seven undefined genera considered putative new genera (pNGenus A to G), and 16 undefined putative new species (seven spp. come from the resolution of the C. maritima complex), await re-assessment of their morphology and additional molecular data, which may result in the recognition of new taxa.

Diversity of Cladosporium (Cladosporiales, Cladosporiaceae) species in marine environments and report on five new species

Cladosporium species are cosmopolitan fungi, characterized by olivaceous or dark colonies with coronate conidiogenous loci and conidial hila with a central convex dome surrounded by a raised periclinal rim. Cladosporium species have also been discovered in marine environments. Although many studies have been performed on the application of marine originated Cladosporium species, taxonomic studies on these species are scarce. We isolated Cladosporium species from three under-studied habitats (sediment, seawater, and seaweed) in two districts including an intertidal zone in the Republic of Korea and the open sea in the Western Pacific Ocean. Based on multigenetic marker analyses (for the internal transcribed spacer, actin, and translation elongation factor 1), we identified fourteen species, of which five were found to represent new species. These five species were C.lagenariiformesp. nov., C.maltirimosumsp. nov., C.marinumsp. nov. in the C.cladosporioides species complex, C.snafimbriatumsp. nov. in the C.herbarum species complex, and C.marinisedimentumsp. nov. in the C.sphaerospermum species complex. Morphological characteristics of the new species and aspects of differences with the already known species are described herein together with molecular data.

Physiological Properties of Three Pelagic Fungi Isolated from the Atlantic Ocean

Oceanic fungi are widely understudied compared to their terrestrial counterparts. However, they have been shown to be important degraders of organic matter in the global pelagic oceans. By examining the physiological characteristics of fungi isolated from the pelagic waters of the ocean it is possible to infer specific functions of each species in the biogeochemical processes that occur in the marine ecosystem. In this study, we isolated three pelagic fungi from different stations and depths across a transect in the Atlantic Ocean. We identified two yeasts [(Scheffersomyces spartinae (Debaryomycetaceae, Saccharomycetes, Ascomycota) and Rhodotorula sphaerocarpa (Sporidiobolaceae, Microbotryomycetes, Basidiomycota)], and the hyphae-morphotype fungus Sarocladium kiliense (Hypocreales, Sordariomycetes, Ascomycota), and conducted physiological experiments to investigate their preferred carbon uptake as well as their growth patterns under different environmental conditions. Despite their taxonomic and morphological differences, all species exhibited a high tolerance towards a wide range of salinities (0–40 g/L) and temperatures (5–35 °C). Furthermore, a shared metabolic preference for oxidizing amino acids was found among all fungal isolates. Collectively, this study provides relevant information on the physiological properties of oceanic pelagic fungi, revealing a high tolerance towards salinity and temperature changes, ultimately contributing to understanding their ecology and distribution in the oceanic water column.

New Dibenzo-α-pyrone Derivatives with α-Glucosidase Inhibitory Activities from the Marine-Derived Fungus Alternaria alternata

Three new dibenzo-α-pyrone derivatives, alternolides A-C (1-3), and seven known congeners (4-10) were isolated from the marine-derived fungus of Alternaria alternata LW37 assisted by the one strain-many compounds (OSMAC) strategy. The structures of 1-3 were established by extensive spectroscopic analyses, and their absolute configurations were determined by modified Snatzke's method and electronic circular dichroism (ECD) calculations. Compounds 6 and 7 showed good 1,1-diphenyl-2-picrylhydrazyl (DPPH) antioxidant scavenging activities with IC₅₀ values of 83.94 ± 4.14 and 23.60 ± 1.23 µM, respectively. Additionally, 2, 3 and 7 exhibited inhibitory effects against α-glucosidase with IC₅₀ values of 725.85 ± 4.75, 451.25 ± 6.95 and 6.27 ± 0.68 µM, respectively. The enzyme kinetics study indicated 2 and 3 were mixed-type inhibitors of α-glucosidase with K_i values of 347.0 and 108.5 µM, respectively. Furthermore, the interactions of 2, 3 and 7 with α-glucosidase were investigated by molecular docking.

Screening of Insecticidal and Antifungal Activities of the Culturable Fungi Isolated from the Intertidal Zones of Qingdao, China

Numerous studies focused on drug discovery perspective have proved the great potential for exploration of marine-derived fungi to seek bioactive chemicals. Yet, marine-derived fungi are less explored compared to their terrestrial counterparts. Here, 181 fungal strains (134 species) isolated from marine algae and sediment in Chinese intertidal zones were screened to reveal bioactivities using brine shrimp, green peach aphid and plant pathogens as targets. Fermentation supernatants of 85 fungal strains exhibited a high lethality (>70%) of brine shrimp at 24 h, and 14 strains appeared to be acute-toxic as featured by more than 75% mortality at 4 h, indicating efficient insecticidal bioactivity. The crude extracts of 34 strains displayed high toxicity to green peach aphid with more than 70% of mortality at 48 h. For the plant pathogens tested, the inhibitory rates of eight fungal strains affiliated with Alternaria (AS3, AS4), Amphichorda (AS7), Aspergillus (AS14), Chaetomium (AS21), Penicillium (AS46), Purpureocillium (AS55) and Trichoderma (AS67) were equal or higher than that of the positive Prochloraz, and five of them (AS7, AS14, AS21, AS55, AS67) were also strongly toxic to brine shrimp or aphid. Our findings indicate broad potential for exploration of marine-derived fungi as candidate resources to pursue bioactive compounds in controlling agricultural pests and pathogens.

Ecological and Oceanographic Perspectives in Future Marine Fungal Taxonomy

Marine fungi are an ecological rather than a taxonomic group that has been widely researched. Significant progress has been made in documenting their phylogeny, biodiversity, ultrastructure, ecology, physiology, and capacity for degradation of lignocellulosic compounds. This review (concept paper) summarizes the current knowledge of marine fungal diversity and provides an integrated and comprehensive view of their ecological roles in the world's oceans. Novel terms for 'semi marine fungi' and 'marine fungi' are proposed based on the existence of fungi in various oceanic environments. The major maritime currents and upwelling that affect species diversity are discussed. This paper also forecasts under-explored regions with a greater diversity of marine taxa based on oceanic currents. The prospects for marine and semi-marine mycology are highlighted, notably, technological developments in culture-independent sequencing approaches for strengthening our present understanding of marine fungi's ecological roles.

Diversity, Abundance, and Ecological Roles of Planktonic Fungi in Marine Environments

Fungi are considered terrestrial and oceans are a “fungal desert”. However, with the considerable progress made over past decades, fungi have emerged as morphologically, phylogenetically, and functionally diverse components of the marine water column. Although their communities are influenced by a plethora of environmental factors, the most influential include salinity, temperature, nutrients, and dissolved oxygen, suggesting that fungi respond to local environmental gradients. The biomass carbon of planktonic fungi exhibits spatiotemporal dynamics and can reach up to 1 μg CL⁻¹ of seawater, rivaling bacteria on some occasions, which suggests their active and important role in the water column. In the nutrient-rich coastal water column, there is increasing evidence for their contribution to biogeochemical cycling and food web dynamics on account of their saprotrophic, parasitic, hyper-parasitic, and pathogenic attributes. Conversely, relatively little is known about their function in the open-ocean water column. Interestingly, methodological advances in sequencing and omics approach, the standardization of sequence data analysis tools, and integration of data through network analyses are enhancing our current understanding of the ecological roles of these multifarious and enigmatic members of the marine water column. This review summarizes the current knowledge of the diversity and abundance of planktonic fungi in the world’s oceans and provides an integrated and holistic view of their ecological roles.

New Antibacterial Chloro-Containing Polyketides from the Alga-Derived Fungus Asteromyces cruciatus KMM 4696

Six new polyketides acrucipentyns A–F (1–6) were isolated from the alga-derived fungus Asteromyces cruciatus KMM 4696. Their structures were established based on spectroscopic methods. The absolute configurations of acrucipentyn A was assigned by the modified Mosher’s method and ROESY data analysis. Acrucipentyns A–E were identified to be the very first examples of chlorine-containing asperpentyn-like compounds. The cytotoxic and antimicrobial activities of the isolated compounds were examined. Acrucipentyns A–F were found as antimicrobial agents, which inhibited sortase A enzyme activity, bacterial growth and biofilm formation of Staphylococcus aureus and decreased LDH release from human keratinocytes HaCaT in S. aureus skin infection in an in vitro model.

Brunneosporopsis yunnanensis gen. et sp. nov. and Allocryptovalsa xishuangbanica sp. nov., New Terrestrial Sordariomycetes from Southwest China

Three fungal taxa were collected on dead branches of wood during fieldwork in Sichuan and Yunnan Provinces, China. The new generic name Brunneosporopsis gen. nov. and species B. yunnanensis sp. nov. are introduced for a novel taxon characterized by globose to subglobose and dark olivacous-brown conidia. Phylogenetic analyses based on combined LSU, SSU and tef1-α loci strongly support the monophyly of this taxon and place it in the subclass Diaporthomycetidae. It could not be assigned to any currently recognized families in the subclass and was, therefore, placed in the Diaporthomycetidae genera incertae sedis. A second taxon represents a new species in Allocryptovalsa based on an analysis of the sequence datasets of ITS and btub loci of the novel, brown-spored sexual morphic species. This taxon is described here as A. xishuangbanica sp. nov. An interesting hypocrealean fungus producing synnemata, Stilbocrea gracilipes, was collected from dead wood of an unknown host from Sichuan Province and is reported here, with asexual morph from both the host and culture as well as LSU, ITS, tef1-α, rpb2 and rpb1 sequence data.

Communities of culturable yeasts and yeast-like fungi in oligotrophic hypersaline coastal waters of the Arabian Gulf surrounding Qatar

This report is the first investigation of yeast biodiversity from the oligotrophic hypersaline coastal waters of the Arabian Gulf surrounding Qatar. Yeasts and yeast-like fungi, were cultured from seawater sampled at 13 coastal areas surrounding Qatar over a period of 2 years (December 2013-September 2015). Eight hundred and forty-two isolates belonging to 82 species representing two phyla viz., Ascomycota (23 genera) and Basidiomycota (16 genera) were identified by molecular sequencing. The results indicated that the coastal waters of the Qatari oligotrophic marine environment harbor a diverse pool of yeast species, most of which have been reported from terrestrial, clinical and aquatic sources in various parts of the world. Five species, i.e., Candida albicans, C. parapsilosis, C. tropicalis, Pichia kudriavzevii and Meyerozyma guilliermondii (n = 252/842; 30% isolates) are known as major opportunistic human pathogens. Fifteen species belonging to nine genera (n = 498/842; 59%) and 12 species belonging to seven genera (n = 459/842; 55%) are hydrocarbon degrading yeast and pollution indicator yeast species, respectively. Ascomycetous yeasts were predominant (66.38%; 559/842) as compared to their basidiomycetous counterparts (33.6%; 283/842). The most isolated yeast genera were Candida (28%; 236/842) (e.g., C. aaseri, C. boidinii, C. glabrata, C. intermedia, C. oleophila, C. orthopsilosis, C. palmioleophila, C. parapsilosis, C. pseudointermedia, C. rugopelliculosa, C. sake, C. tropicalis and C. zeylanoides), Rhodotorula (12.7%; 107/842), Naganishia (8.4%; 71/842), Aureobasidium (7.4%; 62/842), Pichia (7.3%; 62/842), and Debaryomyces (6.4%; 54/842). A total of eleven yeast species ( n = 38) isolated in this study are reported for the first time from the marine environment. Chemical testing demonstrated that seven out of the 13 sites had levels of total petroleum hydrocarbons (TPH) ranging from 200 to 900 µg/L, whereas 6 sites showed higher TPH levels (> 1000-21000 µg/L). The results suggest that the yeast community structure and density are impacted by various physico-chemical factors, namely total organic carbon, dissolved organic carbon and sulphur.

How Do Fungi Survive in the Sea and Respond to Climate Change?

With the over 2000 marine fungi and fungal-like organisms documented so far, some have adapted fully to life in the sea, while some have the ability to tolerate environmental conditions in the marine milieu. These organisms have evolved various mechanisms for growth in the marine environment, especially against salinity gradients. This review highlights the response of marine fungi, fungal-like organisms and terrestrial fungi (for comparison) towards salinity variations in terms of their growth, spore germination, sporulation, physiology, and genetic adaptability. Marine, freshwater and terrestrial fungi and fungal-like organisms vary greatly in their response to salinity. Generally, terrestrial and freshwater fungi grow, germinate and sporulate better at lower salinities, while marine fungi do so over a wide range of salinities. Zoosporic fungal-like organisms are more sensitive to salinity than true fungi, especially Ascomycota and Basidiomycota. Labyrinthulomycota and marine Oomycota are more salinity tolerant than saprolegniaceous organisms in terms of growth and reproduction. Wide adaptability to saline conditions in marine or marine-related habitats requires mechanisms for maintaining accumulation of ions in the vacuoles, the exclusion of high levels of sodium chloride, the maintenance of turgor in the mycelium, optimal growth at alkaline pH, a broad temperature growth range from polar to tropical waters, and growth at depths and often under anoxic conditions, and these properties may allow marine fungi to positively respond to the challenges that climate change will bring. Other related topics will also be discussed in this article, such as the effect of salinity on secondary metabolite production by marine fungi, their evolution in the sea, and marine endophytes.

Predicting global numbers of teleomorphic ascomycetes

Sexual reproduction is the basic way to form high genetic diversity and it is beneficial in evolution and speciation of fungi. The global diversity of teleomorphic species in Ascomycota has not been estimated. This paper estimates the species number for sexual ascomycetes based on five different estimation approaches, viz. by numbers of described fungi, by fungus:substrate ratio, by ecological distribution, by meta-DNA barcoding or culture-independent studies and by previous estimates of species in Ascomycota. The assumptions were made with the currently most accepted, “2.2–3.8 million” species estimate and results of previous studies concluding that 90% of the described ascomycetes reproduce sexually. The Catalogue of Life, Species Fungorum and published research were used for data procurement. The average value of teleomorphic species in Ascomycota from all methods is 1.86 million, ranging from 1.37 to 2.56 million. However, only around 83,000 teleomorphic species have been described in Ascomycota and deposited in data repositories. The ratio between described teleomorphic ascomycetes to predicted teleomorphic ascomycetes is 1:22. Therefore, where are the undiscovered teleomorphic ascomycetes? The undescribed species are no doubt to be found in biodiversity hot spots, poorly-studied areas and species complexes. Other poorly studied niches include extremophiles, lichenicolous fungi, human pathogens, marine fungi, and fungicolous fungi. Undescribed species are present in unexamined collections in specimen repositories or incompletely described earlier species. Nomenclatural issues, such as the use of separate names for teleomorph and anamorphs, synonyms, conspecific names, illegitimate and invalid names also affect the number of described species. Interspecies introgression results in new species, while species numbers are reduced by extinctions.

Xylaria feejeensis, SRNE2BP a Fungal Endophyte with Biocontrol Properties to Control Early Blight and Fusarium Wilt Disease in Tomato and Plant Growth Promotion Activity

Over the past decade endophytic fungi have been known as a source of secondary metabolites with the ability to act as a biocontrol agents. Xylaria feejeensis, SRNE2BP a fungal endophyte isolated from a mangrove tree exhibited antagonistic activity against two fungal pathogens of tomato. Crude extract of X. feejeensis SRNE2BP significantly inhibited Fusarium oxysporum MFLUCC 19-0157 growth as shown approximately 60-75% in in vitro and in situ assays. Both assays showed that the endophyte also inhibited mycelium formation of Alternaria solani MFLUCC 19-0093 by 56% and 87%, respectively. The half maximal inhibitory concentration of X. feejeensis SRNE2BP crude extract against A. solani and F. oxysporum was approximately 7 mg/l. Crude extract and mycelium of X. feejeensis SRNE2BP showed potential in controlling early blight and fusarium wilt disease in tomato, respectively. Seedlings from seeds coated with crude extract of X. feejeensis SRNE2BP had lower disease severity (31.71%) of early blight disease compared to un-treated seeds (57.13%). Soil treated with 10% endophytic mycelium not only reduced fusarium wilt in tomato plant (55.55% severity compared with 91.66% in un-treated soil) but also promoted seed emergence and growth of tomato. Structure analysis revealed that 12 secondary metabolites, especially mellein derivatives, are major components of the crude extract of X. feejeensis SRNE2BP. These compounds could be responsible for antifungal activities; however, further study is required. Our findings strongly suggest that colonization with this fungal endophyte can be beneficial to the host plant especially with regards to plant growth promotion and broad antagonistic activity.

Basal Parasitic Fungi in Marine Food Webs-A Mystery Yet to Unravel

Although aquatic and parasitic fungi have been well known for more than 100 years, they have only recently received increased awareness due to their key roles in microbial food webs and biogeochemical cycles. There is growing evidence indicating that fungi inhabit a wide range of marine habitats, from the deep sea all the way to surface waters, and recent advances in molecular tools, in particular metagenome approaches, reveal that their diversity is much greater and their ecological roles more important than previously considered. Parasitism constitutes one of the most widespread ecological interactions in nature, occurring in almost all environments. Despite that, the diversity of fungal parasites, their ecological functions, and, in particular their interactions with other microorganisms remain largely speculative, unexplored and are often missing from current theoretical concepts in marine ecology and biogeochemistry. In this review, we summarize and discuss recent research avenues on parasitic fungi and their ecological potential in marine ecosystems, e.g., the fungal shunt, and emphasize the need for further research.

Insights on Lulworthiales Inhabiting the Mediterranean Sea and Description of Three Novel Species of the Genus Paralulworthia

The order Lulworthiales, with its sole family Lulworthiaceae, consists of strictly marine genera found on a wide range of substrates such as seagrasses, seaweeds, and seafoam. Twenty-one unidentified Lulworthiales were isolated in previous surveys aimed at broadening our understanding of the biodiversity hosted in the Mediterranean Sea. Here, these organisms, mostly found in association with Posidonia oceanica and with submerged woods, were examined using thorough multi-locus phylogenetic analyses and morphological observations. Maximum-likelihood and Bayesian phylogeny based on nrITS, nrSSU, nrLSU, and four protein-coding genes led to the introduction of three novel species of the genus Paralulworthia: P. candida, P. elbensis, and P. mediterranea. Once again, the marine environment is a confirmed huge reservoir of novel fungal lineages with an under-investigated biotechnological potential waiting to be explored.

Fouling communities of microscopic fungi on various substrates of the Black Sea

Fungi are the most active biodeteriorators of natural and man-made materials. The article presents generalizations of the studies (2001–2019) of communities of microscopic fungi within biofilms on various substrates: shells of live Mytilus (Mytilus galloprovincialis, 670 specimens) and Ostreidae (Crassostrea gigas, 90 specimens), fragments of driftwood (over 7,000), stones (40), concrete of hydrotechnical constructions along the shoreline (80) and wood between concrete blocks in constructions on the shores (80). The studies were carried out in Odessa Oblast, the coastal zone of Sevastopol and open area of the Black Sea. There were identified 123 species of micromycetes, belonging to 65 genera, 33 families, 21 orders, 10 classes, 4 divisions, 2 kingdoms: Fungi and Chromista (fungi-like organisms). The Chromista kingdom was represented by 1 species – Ostracoblabe implexa, on shells of C. gigas. The number of species of micromycetes on various substrates varied 23 (wood between concrete blocks of hydrotechnical constructions) to 74 (shells of M. galloprovincialis at the depths of 3 and 6 m). On all the substrates, the following species were found; Alternaria alternata, Botryotrichum murorum. The communities were found to contain pathogenic fungi Aspergillus fumigatus (shells of mollusks, stones, concrete), A. terreus (concrete), Fusarium oxysporum, Pseudallescheria boydii (shells of mollusks). The best representation was seen for the Pleosporales order – from 12.9% (shells of M. galloprovincialis, 0.3 m depth) to 33.3% (shells of C. gigas) of the species composition. Toxin-producing species of Microascales in mycological communities accounted for 1.6% (driftwood) to 40.0% (concrete), and were also observed on shells of Bivalvia – 11.1–32.3%. Similarity of species composition of mycological communities according to Bray-Curtis coefficient varied 21.1% (driftwood and concrete, 10 shared species) to 72.7% (shells of M. galloprovincialis, the depths of 3 and 7 m and shells of C. gigas, 45 shared species). Using graphs of indices of mean taxonomic distinctness (AvTD, Δ+) and variation (Variation in Taxonomic Distinctness index, VarTD, Λ+), we determined deviations of taxonomic structure of the studied mycological communities from the level of mean expected values, calculated based on the list of species, taking into account their systematic positions. The lowest values of index Δ+ were determined for communities on shells of M. galloprovincialis, 0.3 m depth, driftwood, stones and concrete. These communities had uneven distribution of species according to higher taxonomic ranks and minimum number of the highest taxa: 4–6 classes, 1–2 divisions, Fungi kingdom. Disproportion in species composition with decrease in the number of the highest taxa occurred in extreme environmental conditions. Using index Λ+, we found that the most complex taxonomic structure of fungi communities has developed on concrete and shells of C. gigas. In mycological communities on those substrates, the number of species was low (25 and 46), but they belonged to 4–7 classes, 2–3 divisions, 1–2 kingdoms. To compare the structures of mycological communities that have developed in such substrates in biotopes sea, sea-land-air, land-air, we compiled a list of fungi based on the literature data, which, taking into account our data, comprised 445 species of 240 genera, 103 families, 51 orders, 15 classes, 5 divisions, 2 kingdoms. The analysis revealed that on substrates with similar chemical composition, in all the biotopes, the species of the same divisions dominated (genus and family may vary). Therefore, in the biotope land-air – Hypocreales, Pleosporales, Eurotiales (genera Acremonium, Fusarium, Alternaria, Aspergillus, Penicillium); sea – Pleosporales, Eurotiales, Microascales (Alternaria, Aspergillus, Penicillium, Corollospora); sea-land-air – Pleosporales, Microascales (Alternaria, Leptosphaeria, Aspergillus, Penicillium, Corollospora, Halosarpheia). Monitoring of species composition of myxomycetes is needed in farms that cultivate industrial objects, recreation sites, various buildings for prevention of mycotoxin intoxication and infestation by mycodermatoses and other diseases caused by opportunistic and pathogenic fungi.

Fouling communities of microscopic fungi on various substrates of the Black Sea

Fungi are the most active biodeteriorators of natural and man-made materials. The article presents generalizations of the studies (2001–2019) of communities of microscopic fungi within biofilms on various substrates: shells of live Mytilus (Mytilus galloprovincialis, 670 specimens) and Ostreidae (Crassostrea gigas, 90 specimens), fragments of driftwood (over 7,000), stones (40), concrete of hydrotechnical constructions along the shoreline (80) and wood between concrete blocks in constructions on the shores (80). The studies were carried out in Odessa Oblast, the coastal zone of Sevastopol and open area of the Black Sea. There were identified 123 species of micromycetes, belonging to 65 genera, 33 families, 21 orders, 10 classes, 4 divisions, 2 kingdoms: Fungi and Chromista (fungi-like organisms). The Chromista kingdom was represented by 1 species – Ostracoblabe implexa, on shells of C. gigas. The number of species of micromycetes on various substrates varied 23 (wood between concrete blocks of hydrotechnical constructions) to 74 (shells of M. galloprovincialis at the depths of 3 and 6 m). On all the substrates, the following species were found; Alternaria alternata, Botryotrichum murorum. The communities were found to contain pathogenic fungi Aspergillus fumigatus (shells of mollusks, stones, concrete), A. terreus (concrete), Fusarium oxysporum, Pseudallescheria boydii (shells of mollusks). The best representation was seen for the Pleosporales order – from 12.9% (shells of M. galloprovincialis, 0.3 m depth) to 33.3% (shells of C. gigas) of the species composition. Toxin-producing species of Microascales in mycological communities accounted for 1.6% (driftwood) to 40.0% (concrete), and were also observed on shells of Bivalvia – 11.1–32.3%. Similarity of species composition of mycological communities according to Bray-Curtis coefficient varied 21.1% (driftwood and concrete, 10 shared species) to 72.7% (shells of M. galloprovincialis, the depths of 3 and 7 m and shells of C. gigas, 45 shared species). Using graphs of indices of mean taxonomic distinctness (AvTD, Δ+) and variation (Variation in Taxonomic Distinctness index, VarTD, Λ+), we determined deviations of taxonomic structure of the studied mycological communities from the level of mean expected values, calculated based on the list of species, taking into account their systematic positions. The lowest values of index Δ+ were determined for communities on shells of M. galloprovincialis, 0.3 m depth, driftwood, stones and concrete. These communities had uneven distribution of species according to higher taxonomic ranks and minimum number of the highest taxa: 4–6 classes, 1–2 divisions, Fungi kingdom. Disproportion in species composition with decrease in the number of the highest taxa occurred in extreme environmental conditions. Using index Λ+, we found that the most complex taxonomic structure of fungi communities has developed on concrete and shells of C. gigas. In mycological communities on those substrates, the number of species was low (25 and 46), but they belonged to 4–7 classes, 2–3 divisions, 1–2 kingdoms. To compare the structures of mycological communities that have developed in such substrates in biotopes sea, sea-land-air, land-air, we compiled a list of fungi based on the literature data, which, taking into account our data, comprised 445 species of 240 genera, 103 families, 51 orders, 15 classes, 5 divisions, 2 kingdoms. The analysis revealed that on substrates with similar chemical composition, in all the biotopes, the species of the same divisions dominated (genus and family may vary). Therefore, in the biotope land-air – Hypocreales, Pleosporales, Eurotiales (genera Acremonium, Fusarium, Alternaria, Aspergillus, Penicillium); sea – Pleosporales, Eurotiales, Microascales (Alternaria, Aspergillus, Penicillium, Corollospora); sea-land-air – Pleosporales, Microascales (Alternaria, Leptosphaeria, Aspergillus, Penicillium, Corollospora, Halosarpheia). Monitoring of species composition of myxomycetes is needed in farms that cultivate industrial objects, recreation sites, various buildings for prevention of mycotoxin intoxication and infestation by mycodermatoses and other diseases caused by opportunistic and pathogenic fungi.

https://botryosphaeriales.org/, an online platform for up-to-date classification and account of taxa of Botryosphaeriales

Fungi are eukaryotes that inhabit various ecosystems worldwide and have a decomposing effect that other organisms cannot replace. Fungi are divided into two main groups depending on how their sexual spores are formed, viz. Ascomycota and Basidiomycota. The members of Botryosphaeriales (Dothideomycetes, Ascomycota) are ubiquitous. They are pathogenic on a wide range of hosts, causing diverse diseases including dieback, canker, leaf spots and root rots and are also reported as saprobes and endophytes worldwide. As an important fungal group, of which most are plant pathogens, it is necessary to organize data and information on Botryosphaeriales so that scientific literature can be used effectively. For this purpose, a new website, https://botryosphaeriales.org is established to gather all published data together with updates on the present taxonomy of Botryosphaeriales. The website consists of an easy-to-operate searching system and provides an up-to-date classification together with accounts of Botryosphaeriales taxa, including colour illustrations, descriptions, notes and numbers of species in each genus, as well as their classification. Thus, readers will be able to obtain information on botryosphaerialean taxa through this platform. Database URL: https://botryosphaeriales.org/.

Mangrove Dieback and Leaf Disease in Sonneratia apetala and Sonneratia caseolaris in Vietnam

Even though survival rates for mangrove restoration in Vietnam have often been low, there is no information on fungal pathogens associated with mangrove decline in Vietnam. Therefore, this research was undertaken to assess the overall health of mangrove afforestation in Thanh Hoa Province and fungal pathogens associated with tree decline. From a survey of 4800 Sonneratia trees, the incidence of disorders was in the order of pink leaf spot > shoot dieback > black leaf spot for S. caseolaris and black leaf spot > shoot dieback > pink leaf spot for S. apetala. Approximately 12% of S. caseolaris trees had both pink leaf spot and shoot dieback, while only 2% of S. apetala trees had black leaf spot and shoot dieback. Stem and leaf samples were taken from symptomatic trees and fungi were cultured in vitro. From ITS4 and ITS5 analysis, four main fungal genera causing leaf spots and shoot dieback on the two Sonneratia species were identified. The most frequently isolated fungal taxa were Curvularia aff. tsudae (from black leaf spot),Neopestalotiopsis sp.1 (from stem dieback), Pestalotiopsis sp.1 (from pink leaf spot), and Pestalotiopsis sp.4a (from black leaf spot). The pathogenicity of the four isolates was assessed by under-bark inoculation of S. apetala and S. caseolaris seedlings in a nursery in Thai Binh Province. All isolates caused stem lesions, and Neopestalotiopsis sp.1 was the most pathogenic. Thus, investigation of fungal pathogens and their impact on mangrove health should be extended to other afforestation projects in the region, and options for disease management need to be developed for mangrove nurseries.

Ecology and Evolution of Marine Fungi With Their Adaptation to Climate Change

Climate change agitates interactions between organisms and the environment and forces them to adapt, migrate, get replaced by others, or extinct. Marine environments are extremely sensitive to climate change that influences their ecological functions and microbial community including fungi. Fungi from marine habitats are engaged and adapted to perform diverse ecological functions in marine environments. Several studies focus on how complex interactions with the surrounding environment affect fungal evolution and their adaptation. However, a review addressing the adaptation of marine fungi to climate change is still lacking. Here we have discussed the adaptations of fungi in the marine environment with an example of Hortaea werneckii and Aspergillus terreus which may help to reduce the risk of climate change impacts on marine environments and organisms. We address the ecology and evolution of marine fungi and the effects of climate change on them to explain the adaptation mechanism. A review of marine fungal adaptations will show widespread effects on evolutionary biology and the mechanism responsible for it.

Fungal Biodiversity in Salt Marsh Ecosystems

This review brings together the research efforts on salt marsh fungi, including their geographical distribution and host association. A total of 486 taxa associated with different hosts in salt marsh ecosystems are listed in this review. The taxa belong to three phyla wherein Ascomycota dominates the taxa from salt marsh ecosystems accounting for 95.27% (463 taxa). The Basidiomycota and Mucoromycota constitute 19 taxa and four taxa, respectively. Dothideomycetes has the highest number of taxa, which comprises 47.12% (229 taxa), followed by Sordariomycetes with 167 taxa (34.36%). Pleosporales is the largest order with 178 taxa recorded. Twenty-seven genera under 11 families of halophytes were reviewed for its fungal associates. Juncus roemerianus has been extensively studied for its associates with 162 documented taxa followed by Phragmites australis (137 taxa) and Spartina alterniflora (79 taxa). The highest number of salt marsh fungi have been recorded from Atlantic Ocean countries wherein the USA had the highest number of species recorded (232 taxa) followed by the UK (101 taxa), the Netherlands (74 taxa), and Argentina (51 taxa). China had the highest number of salt marsh fungi in the Pacific Ocean with 165 taxa reported, while in the Indian Ocean, India reported the highest taxa (16 taxa). Many salt marsh areas remain unexplored, especially those habitats in the Indian and Pacific Oceans areas that are hotspots of biodiversity and novel fungal taxa based on the exploration of various habitats.

Untargeted Metabolomics Approach for the Discovery of Environment-Related Pyran-2-ones Chemodiversity in a Marine-Sourced Penicillium restrictum

Very little is known about chemical interactions between fungi and their mollusc host within marine environments. Here, we investigated the metabolome of a Penicillium restrictum MMS417 strain isolated from the blue mussel Mytilus edulis collected on the Loire estuary, France. Following the OSMAC approach with the use of 14 culture media, the effect of salinity and of a mussel-derived medium on the metabolic expression were analysed using HPLC-UV/DAD-HRMS/MS. An untargeted metabolomics study was performed using principal component analysis (PCA), orthogonal projection to latent structure discriminant analysis (O-PLSDA) and molecular networking (MN). It highlighted some compounds belonging to sterols, macrolides and pyran-2-ones, which were specifically induced in marine conditions. In particular, a high chemical diversity of pyran-2-ones was found to be related to the presence of mussel extract in the culture medium. Mass spectrometry (MS)- and UV-guided purification resulted in the isolation of five new natural fungal pyran-2-one derivatives—5,6-dihydro-6S-hydroxymethyl-4-methoxy-2H-pyran-2-one (1), (6S, 1’R, 2’S)-LL-P880β (3), 5,6-dihydro-4-methoxy-6S-(1’S, 2’S-dihydroxy pent-3’(E)-enyl)-2H-pyran-2-one (4), 4-methoxy-6-(1’R, 2’S-dihydroxy pent-3’(E)-enyl)-2H-pyran-2-one (6) and 4-methoxy-2H-pyran-2-one (7)—together with the known (6S, 1’S, 2’S)-LL-P880β (2), (1’R, 2’S)-LL-P880γ (5), 5,6-dihydro-4-methoxy-2H-pyran-2-one (8), (6S, 1’S, 2’R)-LL-P880β (9), (6S, 1’S)-pestalotin (10), 1’R-dehydropestalotin (11) and 6-pentyl-4-methoxy-2H-pyran-2-one (12) from the mussel-derived culture medium extract. The structures of 1-12 were determined by 1D- and 2D-MMR experiments as well as high-resolution tandem MS, ECD and DP4 calculations. Some of these compounds were evaluated for their cytotoxic, antibacterial, antileishmanial and in-silico PTP1B inhibitory activities. These results illustrate the utility in using host-derived media for the discovery of new natural products.

Potential of Anti-Cancer Activity of Secondary Metabolic Products from Marine Fungi

The promising feature of the fungi from the marine environment as a source for anticancer agents belongs to the fungal ability to produce several compounds and enzymes which contribute effectively against the cancer cells growth. L-asparaginase acts by degrading the asparagine which is the main substance of cancer cells. Moreover, the compounds produced during the secondary metabolic process acts by changing the cell morphology and DNA fragmentation leading to apoptosis of the cancer cells. The current review has analyed the available information on the anticancer activity of the fungi based on the data extracted from the Scopus database. The systematic and bibliometric analysis revealed many of the properties available for the fungi to be the best candidate as a source of anticancer drugs. Doxorubicin, actinomycin, and flavonoids are among the primary chemical drug used for cancer treatment. In comparison, the most anticancer compounds producing fungi are Aspergillus niger, A. fumigatus A. oryzae, A. flavus, A. versicolor, A. terreus, Penicillium citrinum, P. chrysogenum, and P. polonicum and have been used for investigating the anticancer activity against the uterine cervix, pancreatic cancer, ovary, breast, colon, and colorectal cancer.

Global Diversity and Biogeography of the Zostera marina Mycobiome

Seagrasses are marine flowering plants that provide critical ecosystem services in coastal environments worldwide. Marine fungi are often overlooked in microbiome and seagrass studies, despite terrestrial fungi having critical functional roles as decomposers, pathogens, or endophytes in global ecosystems. Here, we characterize the distribution of fungi associated with the seagrass Zostera marina, using leaves, roots, and rhizosphere sediment from 16 locations across its full biogeographic range. Using high-throughput sequencing of the ribosomal internal transcribed spacer (ITS) region and 18S rRNA gene, we first measured fungal community composition and diversity. We then tested hypotheses of neutral community assembly theory and the degree to which deviations suggested that amplicon sequence variants (ASVs) were plant selected or dispersal limited. Finally, we identified a core mycobiome and investigated the global distribution of differentially abundant ASVs. We found that the fungal community is significantly different between sites and that the leaf mycobiome follows a weak but significant pattern of distance decay in the Pacific Ocean. Generally, there was evidence for both deterministic and stochastic factors contributing to community assembly of the mycobiome, with most taxa assembling through stochastic processes. The Z. marina core leaf and root mycobiomes were dominated by unclassified Sordariomycetes spp., unclassified Chytridiomycota lineages (including Lobulomycetaceae spp.), unclassified Capnodiales spp., and Saccharomyces sp. It is clear from the many unclassified fungal ASVs and fungal functional guilds that knowledge of marine fungi is still rudimentary. Further studies characterizing seagrass-associated fungi are needed to understand the roles of these microorganisms generally and when associated with seagrasses.

IMPORTANCE Fungi have important functional roles when associated with land plants, yet very little is known about the roles of fungi associated with marine plants, like seagrasses. In this study, we report the results of a global effort to characterize the fungi associated with the seagrass Zostera marina across its full biogeographic range. Although we defined a putative global core fungal community, it is apparent from the many fungal sequences and predicted functional guilds that had no matches to existing databases that general knowledge of seagrass-associated fungi and marine fungi is lacking. This work serves as an important foundational step toward future work investigating the functional ramifications of fungi in the marine ecosystem.

Phylogenetic assessment and taxonomic revision of Halobyssothecium and Lentithecium (Lentitheciaceae, Pleosporales)

Our studies on lignicolous aquatic fungi in Thailand, Sweden, and the UK resulted in the collection of three new Halobyssothecium species (H. bambusicola, H. phragmitis, H. versicolor) assigned to Lentitheciaceae (Pleosporales, Dothideomycetes). Multi-loci phylogenetic analyses of the combined large subunit, small subunit, internal transcribed spacers of ribosomal DNA, and the translation elongation factor 1-alpha sequence data enabled a revision of the taxa assigned to Lentithecium and the transfer of L. cangshanense, L. carbonneanum, L. kunmingense, L. unicellulare, and L. voraginesporum to Halobyssothecium. Collection of an asexual morph of L. lineare and phylogenetic analysis confirmed its taxonomic placement in Keissleriella. Detailed descriptions and illustrations of H. bambusicola, H. phragmitis, and H. versicolor are provided.

Disentangling the structure and function of mycoplankton communities in the context of marine environmental heterogeneity

Mycoplankton are a diverse and ubiquitous component of marine environments with a suggested role in ocean biogeochemical cycling. Thus far, the patterns of their abundance, structure, and function against spatial environmental heterogeneity remains poorly understood. Based on in silico and experimental evaluation of multiple markers, we adopted the ITS1 region to determine the composition, guilds, and metabolic potential of mycoplankton communities in contrasting marine environments. The trophic status of estuarine (SB1 and SB2) and coastal (DB1 and DB2) sites, but not oceanic (OS) site, was the major factor that determined their abundances. While ascomycetous fungi dominated the estuarine and coastal sites, basidiomycetous fungi were found to dominate the oceanic site. The zoosporic fungi were relatively more abundant in SB1 and DB2 sites compared to the other sites. The relative abundances of the core fungi, namely Cystobasidium, Phlebia, Rhodotorula, Trichoderma, Alternaria, Penicillium, Malassezia, and Aspergillus varied widely across the sites. Additionally, several fungal genera unique to each site were also identified. DB2 site exhibited the lowest fungal richness while the OS site the highest. Conversely, the diversity and evenness were the lowest for the OS site but highest for the SB1 site. Temperature, pH, and chlorophyll-a were strongly associated with spatial diversity patterns. Of the 11 assigned guilds, some guilds particularly were not detected, including plant pathogen-wood saprotroph in DB2, the endophyte-plant pathogen in OS, the animal pathogen in SB1, and fungal parasite in DB1 and SB2. Within core functions-metabolism of amino acids, carbohydrates and energy, fatty acids and lipids, nitrogen, sulfur, and other compounds-several pathways showed spatial variations. Overall, this study not just broadens the taxonomic and metabolic repertoire of marine mycoplankton but also provides the first evidence of how these are shaped by site-scale environmental heterogeneity.

Diversity of fungi associated with macroalgae from an estuarine environment and description of Cladosporium rubrum sp. nov. and Hypoxylon aveirense sp. nov

Fungal communities associated with macroalgae remain largely unexplored. To characterize algicolous fungal communities using culture dependent methods, macroalgae were collected from different sampling sites in the Ria de Aveiro estuary, Portugal. From a collection of 486 isolates that were obtained, 213 representative isolates were selected through microsatellite-primed PCR (MSP-PCR) fingerprinting analysis. The collection yielded 33 different genera, which were identified using the ITS region of the rDNA. The results revealed that the most abundant taxa in all collections were Acremonium-like species: Alternaria, Cladosporium, Leptobacillium and Penicillium. The fungal community composition varied with macroalgae species. Through multilocus phylogenetic analyses based on ITS, tub2, tef1-α and actA sequences, in addition to detailed morphological data, we propose Cladosporium rubrum sp. nov. (type strain=CMG 28=MUM 19.39) and Hypoxylon aveirense sp. nov. (type strain=CMG 29=MUM 19.40) as novel species.

Fungal diversity and community structure from coastal and barrier island beaches in the United States Gulf of Mexico

Fungi are an important and understudied component of coastal biomes including sand beaches. Basic biogeographic diversity data are lacking for marine fungi in most parts of the world, despite their important role in decomposition. We examined intertidal fungal communities at several United States (US) Gulf of Mexico sand beach sites using morphology and ITS rDNA terminal restriction fragment length polymorphism (T-RFLP) analyses. Fungal biogeographical patterns from sand beach detritus (wood, emergent plant [mangrove/ saltmarsh], or marine [algae, seagrass]) from Florida, Mississippi, and Texas were investigated using diversity indices and multivariate analyses. Fungal diversity increased with decreasing latitude at our study sites. Substrate type strongly influenced fungal community structure in this region, with different fungal communities on detrital marine versus emergent substrates, as well as detrital marine versus wood substrates. Thirty-five fungi were identified morphologically, including new regional and host records. Of these, 86% were unique to an individual collection (i.e., sampled once from one site). Rarefaction curves from pooled morphological data from all sites estimate the number of samples required to characterize the mycota of each substrate. As sampling occurred before the Deepwater Horizon oil spill (April-2010), our findings contribute pre-oil spill sand beach biodiversity data and marine fungal distribution trends within this economically important oceanographic region.