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Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions 1,2 . To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores 3 . The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms 4,5 ., (© 2024. The Author(s).)

Novel methods for sampling and characterizing biodiversity hold great promise for re-evaluating patterns of life across the planet. The sampling of airborne spores with a cyclone sampler, and the sequencing of their DNA, have been suggested as an efficient and well-calibrated tool for surveying fungal diversity across various environments. Here we present data originating from the Global Spore Sampling Project, comprising 2,768 samples collected during two years at 47 outdoor locations across the world. Each sample represents fungal DNA extracted from 24 m 3 of air. We applied a conservative bioinformatics pipeline that filtered out sequences that did not show strong evidence of representing a fungal species. The pipeline yielded 27,954 species-level operational taxonomic units (OTUs). Each OTU is accompanied by a probabilistic taxonomic classification, validated through comparison with expert evaluations. To examine the potential of the data for ecological analyses, we partitioned the variation in species distributions into spatial and seasonal components, showing a strong effect of the annual mean temperature on community composition., (© 2024. The Author(s).)

Global biodiversity gradients are generally expected to reflect greater species replacement closer to the equator. However, empirical validation of global biodiversity gradients largely relies on vertebrates, plants, and other less diverse taxa. Here we assess the temporal and spatial dynamics of global arthropod biodiversity dynamics using a beta-diversity framework. Sampling includes 129 sampling sites whereby malaise traps are deployed to monitor temporal changes in arthropod communities. Overall, we encountered more than 150,000 unique barcode index numbers (BINs) (i.e. species proxies). We assess between site differences in community diversity using beta-diversity and the partitioned components of species replacement and richness difference. Global total beta-diversity (dissimilarity) increases with decreasing latitude, greater spatial distance and greater temporal distance. Species replacement and richness difference patterns vary across biogeographic regions. Our findings support long-standing, general expectations of global biodiversity patterns. However, we also show that the underlying processes driving patterns may be regionally linked., (© 2024. The Author(s).)

Background: Antarctica and its unique biodiversity are increasingly at risk from the effects of global climate change and other human influences. A significant recent element underpinning strategies for Antarctic conservation has been the development of a system of Antarctic Conservation Biogeographic Regions (ACBRs). The datasets supporting this classification are, however, dominated by eukaryotic taxa, with contributions from the bacterial domain restricted to Actinomycetota and Cyanobacteriota. Nevertheless, the ice-free areas of the Antarctic continent and the sub-Antarctic islands are dominated in terms of diversity by bacteria. Our study aims to generate a comprehensive phylogenetic dataset of Antarctic bacteria with wide geographical coverage on the continent and sub-Antarctic islands, to investigate whether bacterial diversity and distribution is reflected in the current ACBRs., Results: Soil bacterial diversity and community composition did not fully conform with the ACBR classification. Although 19% of the variability was explained by this classification, the largest differences in bacterial community composition were between the broader continental and maritime Antarctic regions, where a degree of structural overlapping within continental and maritime bacterial communities was apparent, not fully reflecting the division into separate ACBRs. Strong divergence in soil bacterial community composition was also apparent between the Antarctic/sub-Antarctic islands and the Antarctic mainland. Bacterial communities were partially shaped by bioclimatic conditions, with 28% of dominant genera showing habitat preferences connected to at least one of the bioclimatic variables included in our analyses. These genera were also reported as indicator taxa for the ACBRs., Conclusions: Overall, our data indicate that the current ACBR subdivision of the Antarctic continent does not fully reflect bacterial distribution and diversity in Antarctica. We observed considerable overlap in the structure of soil bacterial communities within the maritime Antarctic region and within the continental Antarctic region. Our results also suggest that bacterial communities might be impacted by regional climatic and other environmental changes. The dataset developed in this study provides a comprehensive baseline that will provide a valuable tool for biodiversity conservation efforts on the continent. Further studies are clearly required, and we emphasize the need for more extensive campaigns to systematically sample and characterize Antarctic and sub-Antarctic soil microbial communities. Video Abstract., (© 2024. The Author(s).)

Introduction: The Antarctic McMurdo Dry Valleys are geologically diverse, encompassing a wide variety of soil habitats. These environments are largely dominated by microorganisms, which drive the ecosystem services of the region. While altitude is a well-established driver of eukaryotic biodiversity in these Antarctic ice-free areas (and many non-Antarctic environments), little is known of the relationship between altitude and microbial community structure and functionality in continental Antarctica., Methods: We analysed prokaryotic and lower eukaryotic diversity from soil samples across a 684 m altitudinal transect in the lower Taylor Valley, Antarctica and performed a phylogenic characterization of soil microbial communities using short-read sequencing of the 16S rRNA and ITS marker gene amplicons., Results and Discussion: Phylogenetic analysis showed clear altitudinal trends in soil microbial composition and structure. Cyanobacteria were more prevalent in higher altitude samples, while the highly stress resistant Chloroflexota and Deinococcota were more prevalent in lower altitude samples. We also detected a shift from Basidiomycota to Chytridiomycota with increasing altitude. Several genera associated with trace gas chemotrophy, including Rubrobacter and Ornithinicoccus , were widely distributed across the entire transect, suggesting that trace-gas chemotrophy may be an important trophic strategy for microbial survival in oligotrophic environments. The ratio of trace-gas chemotrophs to photoautotrophs was significantly higher in lower altitude samples. Co-occurrence network analysis of prokaryotic communities showed some significant differences in connectivity within the communities from different altitudinal zones, with cyanobacterial and trace-gas chemotrophy-associated taxa being identified as potential keystone taxa for soil communities at higher altitudes. By contrast, the prokaryotic network at low altitudes was dominated by heterotrophic keystone taxa, thus suggesting a clear trophic distinction between soil prokaryotic communities at different altitudes. Based on these results, we conclude that altitude is an important driver of microbial ecology in Antarctic ice-free soil habitats., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer BA declared a past co-authorship with the author IDH to the handling editor at the time of review., (Copyright © 2023 Mashamaite, Lebre, Varliero, Maphosa, Ortiz, Hogg and Cowan.)

The dispersion of microorganisms through the atmosphere is a continual and essential process that underpins biogeography and ecosystem development and function. Despite the ubiquity of atmospheric microorganisms globally, specific knowledge of the determinants of atmospheric microbial diversity at any given location remains unresolved. Here we describe bacterial diversity in the atmospheric boundary layer and underlying soil at twelve globally distributed locations encompassing all major biomes, and characterise the contribution of local and distant soils to the observed atmospheric community. Across biomes the diversity of bacteria in the atmosphere was negatively correlated with mean annual precipitation but positively correlated to mean annual temperature. We identified distinct non-randomly assembled atmosphere and soil communities from each location, and some broad trends persisted across biomes including the enrichment of desiccation and UV tolerant taxa in the atmospheric community. Source tracking revealed that local soils were more influential than distant soil sources in determining observed diversity in the atmosphere, with more emissive semi-arid and arid biomes contributing most to signatures from distant soil. Our findings highlight complexities in the atmospheric microbiota that are relevant to understanding regional and global ecosystem connectivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Free-living terrestrial mites (Acari) have persisted through numerous glacial cycles in Antarctica. Very little is known, however, of their genetic diversity and distribution, particularly within the Ross Sea region. To redress this gap, we sampled mites throughout the Ross Sea region, East Antarctica, including Victoria Land and the Queen Maud Mountains (QMM), covering a latitudinal range of 72-85 °S, as well as Lauft Island near Mt. Siple (73 °S) in West Antarctica and Macquarie Island (54 o S) in the sub-Antarctic. We assessed genetic diversity using mitochondrial cytochrome c oxidase subunit I gene sequences (COI-5P DNA barcode region), and also morphologically identified voucher specimens. We obtained 130 sequences representing four genera: Nanorchestes ( n = 30 sequences), Stereotydeus ( n = 46), Coccorhagidia ( n = 18) and Eupodes ( n = 36). Tree-based analyses (maximum likelihood) revealed 13 genetic clusters, representing as many as 23 putative species indicated by barcode index numbers (BINs) from the Barcode of Life Datasystems (BOLD) database. We found evidence for geographically-isolated cryptic species, e.g., within Stereotydeus belli and S. punctatus , as well as unique genetic groups occurring in sympatry (e.g., Nanorchestes spp. in QMM). Collectively, these data confirm high genetic divergence as a consequence of geographic isolation over evolutionary timescales. From a conservation perspective, additional targeted sampling of understudied areas in the Ross Sea region should be prioritised, as further diversity is likely to be found in these short-range endemic mites.

Microbial communities can be structured by both deterministic and stochastic processes, but the relative importance of these processes remains unknown. The ambiguity partly arises from an inability to disentangle soil microbial processes from confounding factors, such as aboveground plant communities or anthropogenic disturbance. In this study, we characterized the relative contributions of determinism and stochasticity to assembly processes of soil bacterial communities across a large environmental gradient of undisturbed Antarctic soils. We hypothesized that harsh soils would impose a strong environmental selection on microbial communities, whereas communities in benign soils would be structured largely by dispersal. Contrary to our expectations, dispersal was the dominant assembly mechanism across the entire soil environmental gradient, including benign environments. The microbial community composition reflects slowly changing soil conditions and dispersal limitation of isolated sites. Thus, stochastic processes, as opposed to deterministic, are primary drivers of soil ecosystem assembly across space at our study site. This is especially surprising given the strong environmental constraints on soil microorganisms in one of the harshest environments on the planet, suggesting that dispersal could be a driving force in microbial community assembly in soils worldwide. IMPORTANCE Because of their diversity and ubiquity, microbes provide an excellent means to tease apart how natural communities are structured. In general, ecologists believe that stochastic assembly processes, like random drift and dispersal, should dominate in benign environments while deterministic processes, like environmental filtering, should be prevalent in harsh environments. To help resolve this debate, we analyzed microbial community composition in pristine Antarctic soils devoid of human influence or plant communities for eons. Our results demonstrate that dispersal limitation is a surprisingly potent force of community limitation throughout all soil conditions. Thus, dispersal appears to be a driving force of microbial community assembly, even in the harshest of conditions.

Lakes provide habitat for a diverse array of species and offer a wide range of ecosystem services for humanity. However, they are highly vulnerable as they are not only impacted by adverse actions directly affecting them, but also those on the surrounding environment. Improving knowledge on the processes responsible for community assembly in different biotic components will aid in the protection and restoration of lakes. Studies to date suggested a combination of deterministic (where biotic/abiotic factors act on fitness differences amongst taxa) and stochastic (where dispersal plays a larger factor in community assembly) processes are responsible for structuring biotic communities, but there is no consensus on the relative roles these processes play, and data is lacking for lakes. In the present study, we sampled different biotic components in 34 lakes located on the South Island of New Zealand. To obtain a holistic view of assembly processes in lakes we used metabarcoding to investigate bacteria in the sediment and surface waters, and eukaryotes in the sediment and two different size fractions of the water column. Physicochemical parameters were collected in parallel. Results showed that deterministic processes dominated the assembly of lake communities although the relative importance of variable and homogeneous selection differed among the biotic components. Variable selection was more important in the sediment (SSbact and SSeuks) and for the bacterioplankton (Pbact) while the assembly of the eukaryotic plankton (SPeuks, LPeuks) was driven more by homogeneous selection. The ease of human access to the lakes had a significant effect on lake communities. In particular, clade III of SAR11 and Daphnia pulex were only present in lakes with public access. This study provides insights into the distribution patterns of different biotic components and highlights the value in understanding the drivers of different biological communities within lakes., Competing Interests: Susanna A Wood is an Academic Editor for PeerJ. John K. Pearman, Georgia Thomson-Laing, Lucy Thompson, Sean Waters and Susanna A. Wood are employed by the Cawthron Institute. Marcus J. Vandergoes is employed by GNS Science., (© 2022 Pearman et al.)

Assessing the resilience of polar biota to climate change is essential for predicting the effects of changing environmental conditions for ecosystems. Collembola are abundant in terrestrial polar ecosystems and are integral to food-webs and soil nutrient cycling. Using available literature, we consider resistance (genetic diversity; behavioural avoidance and physiological tolerances; biotic interactions) and recovery potential for polar Collembola. Polar Collembola have high levels of genetic diversity, considerable capacity for behavioural avoidance, wide thermal tolerance ranges, physiological plasticity, generalist-opportunistic feeding habits and broad ecological niches. The biggest threats to the ongoing resistance of polar Collembola are increasing levels of dispersal (gene flow), increased mean and extreme temperatures, drought, changing biotic interactions, and the arrival and spread of invasive species. If resistance capacities are insufficient, numerous studies have highlighted that while some species can recover from disturbances quickly, complete community-level recovery is exceedingly slow. Species dwelling deeper in the soil profile may be less able to resist climate change and may not recover in ecologically realistic timescales given the current rate of climate change. Ultimately, diverse communities are more likely to have species or populations that are able to resist or recover from disturbances. While much of the Arctic has comparatively high levels of diversity and phenotypic plasticity; areas of Antarctica have extremely low levels of diversity and are potentially much more vulnerable to climate change., Competing Interests: The authors declare no financial conflicts associated with this research. Brent J. Sinclair is Editor-in-Chief of Current Research in Insect Science. Given his role, he had no involvement in the evaluation or peer review of this manuscript, and has no access to information regarding its peer review., (© 2022 The Authors. Published by Elsevier B.V.)

Assessing genetic differentiation among natural populations can aid understanding of dispersal patterns and connectivity among habitats. Several molecular markers have become increasingly popular in determining population genetic structure for this purpose. Here, we compared the resolution of mitochondrial cytochrome c oxidase subunit I (COI) and nuclear single nucleotide polymorphism (SNP) markers for detecting population structure among stream insects at small spatial scales. Individuals of three endemic taxa- Coloburiscus humeralis (Ephemeroptera), Zelandobius confusus (Plecoptera), and Hydropsyche fimbriata (Trichoptera)-were collected from forested streams that flow across open pasture in the North Island of New Zealand. Both COI and SNP data indicated limited population structure across the study area, and small differences observed among these species were likely related to their putative dispersal abilities. For example, fine-scale genetic differentiation between and among neighbouring stream populations for H. fimbriata suggests that gene flow, and hence dispersal, may be more limited for this species relative to the others. Based on the generally similar results provided by both types of markers, we suggest that either COI or SNP markers can provide suitable initial estimates of fine-scale population genetic differentiation in stream insects.

The inland soils found on the Antarctic continent represent one of the more challenging environments for microbial life on Earth. Nevertheless, Antarctic soils harbor unique bacterial and archaeal (prokaryotic) communities able to cope with extremely cold and dry conditions. These communities are not homogeneous, and the taxonomic composition and functional capabilities (genomic attributes) of these communities across environmental gradients remain largely undetermined. We analyzed the prokaryotic communities in soil samples collected from across the Shackleton Glacier region of Antarctica by coupling quantitative PCR, marker gene amplicon sequencing, and shotgun metagenomic sequencing. We found that elevation was the dominant factor explaining differences in the structures of the soil prokaryotic communities, with the drier and saltier soils found at higher elevations harboring less diverse communities and unique assemblages of cooccurring taxa. The higher-elevation soil communities also had lower maximum potential growth rates (as inferred from metagenome-based estimates of codon usage bias) and an overrepresentation of genes associated with trace gas metabolism. Together, these results highlight the utility of assessing community shifts across pronounced environmental gradients to improve our understanding of the microbial diversity found in Antarctic soils and the strategies used by soil microbes to persist at the limits of habitability. IMPORTANCE Antarctic soils represent an ideal system to study how environmental properties shape the taxonomic and functional diversity of microbial communities given the relatively low diversity of Antarctic soil microbial communities and the pronounced environmental gradients that occur across soils located in reasonable proximity to one another. Moreover, the challenging environmental conditions typical of most Antarctic soils present an opportunity to investigate the traits that allow soil microbes to persist in some of the most inhospitable habitats on Earth. We used cultivation-independent methods to study the bacterial and archaeal communities found in soil samples collected from across the Shackleton Glacier region of the Transantarctic Mountains. We show that those environmental characteristics associated with elevation have the greatest impact on the structure of these microbial communities, with the colder, drier, and saltier soils found at higher elevations sustaining less diverse communities that were distinct from those in more hospitable soils with respect to their composition, genomic attributes, and overall life-history strategies. Notably, the harsher conditions found in higher-elevation soils likely select for taxa with lower maximum potential growth rates and an increased reliance on trace gas metabolism to support growth.

The subfamily Seirinae (Collembola: Entomobryidae) is among the most diverse suprageneric taxa of epedaphic springtails and is particularly abundant and species-rich in tropical and subtropical regions. Numerous studies have investigated its internal and external phylogenetic relationships, enhancing our understanding on Seirinae systematics. Recent taxonomic efforts have also advanced our knowledge on the subfamily morphology and diversity. In this study, we reevaluate the phylogeny of Seirinae using the mitogenomes of 26 samples from different continents, aiming to discuss recent findings regarding the group systematics, to identify cases of alien species introduced in China and Thailand, and propose new synonyms for Seira spp. Additionally, we describe a new species from Thailand and provide a redescription of Seira brasiliana (Arlé) based on the study of Brazilian and Chinese specimens. Through these efforts, we provide further ground for understanding the evolution, systematics, distribution and taxonomy of the group, contributing to future studies on Seirinae and Entomobryidae. [ABSTRACT FROM AUTHOR]

The use of environmental DNA (eDNA) to assess the presence of biological communities has emerged as a promising monitoring tool in the marine conservation landscape. Moreover, advances in Next-Generation Sequencing techniques, such as DNA metabarcoding, enable multi-species detection in mixed samples, allowing the study of complex ecosystems such as oceanic ones. We aimed at using these molecular-based techniques to characterize cetacean communities, as well as potential prey on the northern coast of Mainland Portugal. During four seasonal campaigns (summer 2021 to winter 2022/2023), seawater samples were collected along with visual records of cetacean occurrence. The eDNA isolated from 64 environmental samples was sequenced in an Illumina platform, with universal primers targeting marine vertebrates. Five cetacean species were identified by molecular detection: common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena) and fin whale (Balaenoptera physalus). Overall, except for the latter (not sighted during the campaigns), this cetacean community composition was similar to that obtained through visual monitoring, and the complementary results suggest their presence in the region all year round. In addition, the positive molecular detections of Balaenoptera physalus are of special relevance since there are no records of this species reported on scientific bibliography in the area. The detection of multiple known prey of the identified dolphins indicates an overlap between predator and prey in the study area, which suggests that these animals may use this coastal area for feeding purposes. While this methodological approach remains in a development stage, the present work highlights the benefits of using eDNA to study marine communities, with specific applications for research on cetacean distribution and feeding ecology. [ABSTRACT FROM AUTHOR]

Marine birds and pinnipeds which come to land to breed, rest and moult are widely known to fertilize adjacent terrestrial ecosystems, with cascading effects on vegetation and other trophic levels. We provide a synthesis of the consequences of allochthonous nutrient enrichment for terrestrial invertebrate communities within and around marine vertebrate aggregation sites and nutrient sources in the High Arctic and Continental and Maritime Antarctic, the most nutrient-poor and environmentally extreme parts of the polar regions. Using a combination of literature review (identifying 19 articles from the Arctic Svalbard archipelago and 12 from different Antarctic locations) and new analyses of available datasets of springtail, mite and tardigrade community composition, we confirmed that terrestrial invertebrate abundance and species richness tended to increase, and their community compositions changed, as a result of marine vertebrate fertilisation in both polar regions. These changes were significantly greater on talus slopes enriched by kittiwakes, guillemots and little auks in the Arctic, as compared to the edges of penguin colonies in the Antarctic. Both these habitat areas were typically abundantly vegetated and provided the most favourable microhabitat conditions for terrestrial invertebrates. The most heavily disturbed and manured areas within Antarctic penguin rookeries and seal wallows, generally on flat or gently sloping ground, were typically characterised by extremely low invertebrate diversity. In the Arctic, only sites directly beneath densely-occupied bird cliffs were to some extent comparably barren. Invertebrate responses are dependent on a combination of vertebrate activity, local topography and vegetation development. [ABSTRACT FROM AUTHOR]

Estimates of global fungal diversity have varied widely, suggesting a range from fewer than one million to over 10 million species, with each of the estimates drawing data from various criteria. In 2022, Fungal Diversity published a special issue on fungal numbers. It had been hoped that the editorial would provide a more accurate account of the numbers of fungi. Instead, it was concluded that this was not possible based on present evidence and, some of the data necessary for accurate assessments was put forward, and the present paper expands on this short article. The review first looks at estimates of fungal numbers and what these estimates are based on. It then presents future research needs that will help us to gain a more accurate estimate of fungal numbers. This includes work that needs to be done in tropical rainforests, where the greatest diversity is expected, where whole rainforests, canopy diversity, and palm fungi are addressed. Case studies for lichens and associated fungi, soil and litter fungi, evidence from particle filtration, freshwater fungi, marine fungi, mushrooms, and yeasts will also be given. Once we have such information, we can obtain a more accurate estimate of fungal numbers. [ABSTRACT FROM AUTHOR]

We analysed internal dispersal of zooplankton by waterbirds (endozoochory) in New Zealand, quantifying zooplankton eggs in faecal droppings collected at two lakes, Lake Rotoroa (Hamilton) and Lake Rotorua. Sixty-seven faecal droppings were collected from Mallard Ducks (20), Canada Geese (11), Greylag Geese (6), Black Swans (20) and Australian Coots (10). Fifty eggs were found, with a mean of 0.75 eggs per dropping, indicating that waterbirds consume zooplankton eggs, and that these pass through the digestive system. No significant difference was observed in the abundance of eggs among waterbird species, and no eggs hatched in the laboratory. Our results suggest that waterbird dispersal of zooplankton in New Zealand is occurring, but numbers being transported are low. Further, as non-native waterbirds such as mallard ducks and geese do not migrate in New Zealand to the extent they do elsewhere, they are likely not primary vectors for zooplankton dispersal. [ABSTRACT FROM AUTHOR]

The microbiome is a key factor in the health, well-being, and success of vertebrates, contributing to the adaptive capacity of the host. However, the impact of geographic and biotic factors that may affect the microbiome of wild birds in polar environments is not well defined. To address this, we determined the bacterial 16S rRNA gene sequence profiles in faecal samples from pygoscelid penguin populations in the Scotia Arc, focusing on gentoo penguins. This mesopredatory group breeds in defined colonies across a wide geographic range. Since diet could influence microbiome structure, we extracted dietary profiles from a eukaryotic 18S rRNA gene sequence profile. The bacterial microbiome profiles were considered in the context of a diverse set of environmental and ecological measures. Integrating wide geographic sampling with bacterial 16S and eukaryotic 18S rRNA gene sequencing of over 350 faecal samples identified associations between the microbiome profile and a suite of geographic and ecological factors. Microbiome profiles differed according to host species, colony identity, distance between colonies, and diet. Interestingly there was also a relationship between the proportion of host DNA (in relation to total 18S rRNA gene signal) and the microbiome, which may reflect gut passage time. Colony identity provided the strongest association with differences in microbiome profiles indicating that local factors play a key role in the microbiome structure of these polar seabirds. This may reflect the influence of local transfer of microbes either via faecal-oral routes, during chick feeding or other close contact events. Other factors including diet and host species also associate with variation in microbiome profile, and in at least some locations, the microbiome composition varies considerably between individuals. Given the variation in penguin microbiomes associated with diverse factors there is potential for disruption of microbiome associations at a local scale that could influence host health, productivity, and immunological competence. The microbiome represents a sensitive indicator of changing conditions, and the implications of any changes need to be considered in the wider context of environmental change and other stressors. [ABSTRACT FROM AUTHOR]

A new marine myxosporean, Myxidium tunisiensis n. sp. (Myxosporea: Myxidiidae), is described infecting the gallbladder of the rough skate Raja radula Delaroche, 1908 (Chondrichthyes: Rajidae) harvested from the Bay of Bizerte, Tunisia. Observed stages of the parasite were floating free in the bile. Plasmodia, disporic or polysporic, contain disporic pansporoblasts measuring 23.0-27.2 μm in maximum diameter and 21.0-25.5 μm in minimum diameter. Mature myxospores, which are elongated, typically fusiform measured 18.6 ± 1.7 (17.2-22.0) μm in length, 8.6 ± 1.2 (7.2-11.2) μm in width and 8.2 ± 0.9 (6.4-10.1) in thickness. Myxospore valves are symmetrical with 9-10 longitudinal striations. Two polar capsules, pyriform, were equal in size, measuring 5.8 ± 0.4 (5.2-6.7) μm in length and 3.1 ± 0.2 (3.0-3.2) μm in width, with 5-6 polar filament turns. The infection was prevalent throughout the year with the highest prevalence in autumn (81.8%) and the lowest in winter (32.3%). The seasonal prevalence of M. tunisiensis n. sp. in the Bay of Bizerte appeared to fluctuate according to seawater temperature. The morphological and morphometrical differences with all Myxidium spp. described so far, complemented by molecular data, prove clearly that the present species is a new member of the genus Myxidium. The SSU rDNA phylogenetic analyses revealed that Myxidium tunisiensis n. sp. clustered within the oligochaete-gallbladder clade in a basal position to the marine subclade of Myxidium baueri and Myxidium coryphaenoideum. While the new species branching pattern is stable in the ML and the BI analyses, it changed in the MP analysis. This is the first molecular study of a Myxidium species infecting an elasmobranch host inhabiting the Mediterranean Sea., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Previous difficulties in arthropod taxonomy (such as limitations in conventional morphological approaches, the possibility of cryptic species and a shortage of knowledgeable taxonomists) has been overcome by the powerful tool of DNA barcoding. This study presents a thorough analysis of DNA barcoding in regards to Pakistani arthropods, which were collected from Lahore's Jinnah Garden. The 88 % (9,451) of the 10,792 specimens that were examined were able to generate DNA barcodes and 83% (8,974) of specimens were assigned 1,361 barcode index numbers (BINs). However, the success rate differed significantly between the orders of arthropods, from 77% for Thysanoptera to an astounding 93% for Diptera. Through morphological exams, DNA barcoding, and cross-referencing with the Barcode of Life Data system (BOLD), the Barcode Index Numbers (BINs) were assigned with a high degree of accuracy, both at the order (100%) and family (98%) levels. Though, identifications at the genus (37%) and species (15%) levels showed room for improvement. This underscores the ongoing need for enhancing and expanding the DNA barcode reference library. This study identified 324 genera and 191 species, underscoring the advantages of DNA barcoding over traditional morphological identification methods. Among the 17 arthropod orders identified, Coleoptera, Diptera, Hemiptera, Hymenoptera, and Lepidoptera from the class Insecta dominated, collectively constituting 94% of BINs. Expected malaise trap Arthropod fauna in Jinnah Garden could contain approximately 2,785 BINs according to Preston log-normal species distribution, yet the Chao-1 Index predicts 2,389.74 BINs. The Simpson Index of Diversity (1-D) is 0.989, signaling high species diversity, while the Shannon Index is 5.77, indicating significant species richness and evenness. These results demonstrated that in Pakistani arthropods, DNA barcoding and BOLD are an invaluable tool for improving taxonomic understanding and biodiversity assessment, opening the door for further eDNA and metabarcoding research. [ABSTRACT FROM AUTHOR]

Background: The processes that shape microbial biogeography are not well understood, and concepts that apply to macroorganisms, like dispersal barriers, may not affect microorganisms in the same predictable ways. To better understand how known macro-scale biogeographic processes can be applied at micro-scales, we examined seagrass associated microbiota on either side of Wallace's line to determine the influence of this cryptic dispersal boundary on the community structure of microorganisms. Communities were examined from twelve locations throughout Indonesia on either side of this theoretical line. Results: We found significant differences in microbial community structure on either side of this boundary (R2 = 0.09; P = 0.001), and identified seven microbial genera as differentially abundant on either side of the line, six of these were more abundant in the West, with the other more strongly associated with the East. Genera found to be differentially abundant had significantly smaller minimum cell dimensions (GLM: t923 = 59.50, P < 0.001) than the overall community. Conclusion: Despite the assumed excellent dispersal ability of microbes, we were able to detect significant differences in community structure on either side of this cryptic biogeographic boundary. Samples from the two closest islands on opposite sides of the line, Bali and Komodo, were more different from each other than either was to its most distant island on the same side. We suggest that limited dispersal across this barrier coupled with habitat differences are primarily responsible for the patterns observed. The cryptic processes that drive macroorganism community divergence across this region may also play a role in the bigeographic patterns of microbiota. [ABSTRACT FROM AUTHOR]

Springtails can occur in large populations on the snow surface. This peculiar habitat hosts specialized winter-active springtails living in colonies and using this seasonal habitat for feeding, effective dispersal and migration. Snow-active species have never been studied in Southern European Alps: the aim of this work is to study snow-active springtails of Adamello-Brenta Nature Park ("PNAB"; Italy), a peripheral mountain range of relevant biogeographic interest using integrative taxonomy. Springtail "bloomings" were sampled for 17 months by an environmental assistant of the park. Nine assemblages of springtails were found when temperatures were higher than 0 °C; eight were monospecific, with a total of five species found. The snow-active springtail fauna found includes both common Central-Northern European nival species like Desoria hiemalis (first record for Italy, although genetically differentiated from Northern Alps populations), Ceratophysella sigillata (known in Italy mainly from caves) and three species likely new to science (Hypogastrura cf. kelmendica sp1, Hypogastrura cf. kelmendica sp2, H. cf. peloponnesica, all belonging to the Hypogastrura socialisgroup). Snow is an important ephemeral habitat for springtails, for the biodiversity hosted and for its importance as an ecological corridor. We could hypothesize that snow, especially in peripheral mountain chains, acts as a fragmentary ephemeral habitat for those cold-adapted springtails. This could constitute a relevant aspect to take into consideration for conservation biology, especially in the context of the ongoing climate change. On the other hand, the Alpine chain probably acts as an ecological barrier for nival species, since isolated species and populations were found in PNAB. [ABSTRACT FROM AUTHOR]

Amphipods are an ecologically diverse group of crustaceans. Due to the limited number of fossil data and common morphological homoplasy, molecular data can be very useful to understand their evolutionary relationships and history. However, despite their global distribution and an increasing number of phylogenetic studies, molecular data from the Southern Hemisphere is considerably limited. Here, I report multigene data (18S, 28S, and COI) of New Zealand endemic freshwater families as well as some other marine taxa. Also, I report two new species/genera that have not been described yet. Phylogenetic analyses were conducted including major amphipod groups to understand phylogenetic placements of New Zealand amphipods. Based on the ML and Bayesian trees, Paracallipe, Paraleptamphopus, and the two unknown species belong to the eusiroids/iphimedioids clade; Parorchestia and a talitrid species clearly belong to talitroids; Paracorophium and Monocorophium were placed within corophiids; Themisto belongs to physosomatans; Josephosella was closely related to other hadzoids. The present study suggests that the Southern and Northern Hemisphere freshwater amphipods are likely to have originated from different marine ancestors. Molecular data from other regions in the Southern Hemisphere will be highly valuable for understanding the phylogeographic histories of amphipods that have shaped the current diversity and distribution. [ABSTRACT FROM AUTHOR]

Context. The Mediterranean fanworm arrived as a non-indigenous species in parts of Australasia, where it has established and then rapidly spread from the initial points of arrival, despite marked differences in environmental conditions compared from its natal habitat in the Mediterranean Sea. Aims. To better understand the invasive capacity of this species in New Zealand. Methods. Maturation, reproductive cycle, and gametogenesis were investigated, with a focus on female gamete development, for a population in Auckland, and the results were compared with those of previous studies in the Mediterranean Sea and Australia. Key results. Egg sizes in female fanworms were highly variable throughout the year; however, a reduced presence of larger eggs was observed from August to November, which could indicate spawning. This Auckland fanworm population also appeared to have a female-skewed sex ratio compared with previous studies where a 1:1 sex ratio was observed. Fanworm maturation was reached at ~6 cm in length, compared with 15 cm in natal populations. Fanworms with body size smaller than 5 cm were not mature and did not produce mature gametes, in contrast to an Australian fanworm population. Conclusions. The observed Mediterranean fanworm population in New Zealand demonstrates reproductive flexibility and high fecundity, contributing to its invasive capacity. Implications. The reproductive biology of a species is important in determining its invasive capacity, and may also be flexible between populations, with implications for effective biosecurity management strategies. [ABSTRACT FROM AUTHOR]

Wastewater originating from the Phetchaburi municipality undergoes treatment in a series of five distinct stages at the King's Royally Initiated Leam Phak Bia Environmental Research and Development Project (LERD) in Phetchaburi province, Thailand. These stages involve a sedimentation (pond 1), three oxidation ponds (ponds 2 to 4), and a final stabilization pond (pond 5). These ponds serve as habitats for macroinvertebrates; consequently, their diversity and composition might be influenced by fluctuations in water quality and seasonal variations. The primary aim of this research was to analyze the diversity and species composition of macroinvertebrate communities concerning varying levels of organic contamination across the five wastewater treatment ponds at LERD. This investigation spanned three seasons: cold season (December 2019), rainy season (July 2020), and hot season (April 2021). The findings revealed that the diversity and species composition of macroinvertebrate communities displayed distinct alterations across multiple environmental gradients, especially identifying the significant influence of organic loading levels observed in ponds 1 to 5. The macroinvertebrate communities exhibited two distinct groupings, with the Chironomidae and Candonidae or ostracods prevailing prominently in ponds 1 and 2 (heterogenous environments). This prevalence was attributed to the high levels of detrital food and the robust resilience of chironomid larvae and ostracods to organic pollution, thriving even in environments characterized by low dissolved oxygen levels. Conversely, the prevalence of snails from the Thiaridae family in ponds 3 to 5 (homogenous environments) indicated improved water quality conditions, notably lower organic matter levels, and a higher dissolved oxygen content. In addition, the study identified seasonal variations in macroinvertebrates, likely influenced by the differing organic loading and environmental conditions. Thus, this research provided insights into the factors shaping macroinvertebrate communities in a wastewater treatment system. [ABSTRACT FROM AUTHOR]

Context. Understanding the impacts of salinity on groundwater microbial communities is imperative, because these communities influence groundwater chemistry, quality, and its suitability for use by humans and the environment. Aim. To assess groundwater salinisation and its influence on groundwater microbial communities within the Murray-Darling Basin (MDB), Australia. Methods. Alluvial aquifers were sampled from 41 bores, within the Lachlan, Murrumbidgee and Murray catchments. Environmental DNA (eDNA), microbial activity and water-quality variables were measured to evaluate microbial communities, which were then correlated with electrical conductivity (EC) and other environmental variables. Results. Our results indicated widespread groundwater salinisation within the MDB, with EC ranging from 63 to 51 257 μS cm-1. The highest EC values were recorded in the Murray catchment; however, mean EC values did not differ significantly among catchments (P > 0.05). The composition of microbial communities differed significantly between sites with low (<3000 μS cm-1) and high (>3000 μS cm-1) EC. Microbial activity, richness and abundances were all greater at low- than high-EC sites. Conclusions. Changes to microbial communities as demonstrated here may have impacts on biogeochemical cycling and ecosystem resilience. Implications. The detrimental ecological impacts of salinity are not limited to groundwater microbes, but present a larger ecological issue affecting all groundwater-dependent ecosystems. [ABSTRACT FROM AUTHOR]

Objective: Roller swabbing of surfaces is an effective way to obtain environmental DNA, but the current DNA extraction method for these samples is equipment heavy, time consuming, and increases potential contamination through multiple handling. Here, we used rollers to swab a dog kennel and compared three DNA extraction approaches (water filtration, roller trimming and direct buffer) using two different platforms (Qiacube, Kingfisher). DNA extraction methods were evaluated based on cost, effort, DNA concentration and PCR result. Results: The roller trim method emerged as the optimal method with the best PCR results, DNA concentration and cost efficiency, while the buffer-based methods were the least labour intensive but produced mediocre PCR results and DNA concentrations. Additionally, the Kingfisher magnetic bead extractions generally ranked higher in all categories over the Qiacube column-based DNA extractions. Ultimately, the ideal DNA extraction method for a particular study is influenced by logistical constraints in the field such as the size of the roller, the availability of cold storage, and time constraints on the project. Our results demonstrate the strengths and weaknesses of each approach, allowing for informed decision making by researchers. [ABSTRACT FROM AUTHOR]

Animal rehabilitation centres provide a unique opportunity to study the microbiome of wild animals because subjects will be handled for their treatment and can therefore be sampled longitudinally. However, rehabilitation may have unintended consequences on the animals' microbiome because of a less varied and suboptimal diet, possible medical treatment and exposure to a different environment and human handlers. Our study describes the gut microbiome of two large seal cohorts, 50 pups (0–30 days old at arrival) and 23 weaners (more than 60 days old at arrival) of stranded harbour seals admitted for rehabilitation at the Sealcentre Pieterburen in the Netherlands, and the effect of rehabilitation on it. Faecal samples were collected from all seals at arrival, two times during rehabilitation and before release. Only seals that did not receive antimicrobial treatment were included in the study. The average time in rehabilitation was 95 days for the pups and 63 days for the weaners. We observed that during rehabilitation, there was an increase in the relative abundance of some of the Campylobacterota spp and Actinobacteriota spp. The alpha diversity of the pups' microbiome increased significantly during their rehabilitation (p-value <0.05), while there were no significant changes in alpha diversity over time for weaners. We hypothesize that aging is the main reason for the observed changes in the pups' microbiome. At release, the sex of a seal pup was significantly associated with the microbiome's alpha (i.e., Shannon diversity was higher for male pups, p-value <0.001) and beta diversity (p-value 0.001). For weaners, variation in the microbiome composition (beta diversity) at release was partly explained by sex and age of the seal (p-values 0.002 and 0.003 respectively). We mainly observed variables known to change the gut microbiome composition (e.g., age and sex) and conclude that rehabilitation in itself had only minor effects on the gut microbiome of seal pups and seal weaners. [ABSTRACT FROM AUTHOR]

Larval behaviour for many of New Zealand's diadromous freshwater fish is inadequately described. Diadromy for many amphidromous species is not obligatory however, and where conditions are suitable, freshwater larval rearing may be facilitated. Where this occurs in lakes, opportunities to document the composition and conditions supporting larval rearing exist. Boat trawling was undertaken across nine lowland lakes in the Lower Waikato over four consecutive winters with a focus on larval galaxiids. Galaxiid larvae were captured in surface water habitats in all but one lake, with banded kōkopu (Galaxias fasciatus) and giant kōkopu (Galaxias argenteus) the most common species detected. One lake, Lake Waahi, consistently resulted in the most galaxiid captures for effort expended. Analyses of larvae from this and other lakes indicated that two sizes predominated in catches and that larger, older larvae were predominantly G. fasciatus while smaller, younger larvae were predominantly G. argenteus. Stomach contents indicated that two non-native zooplankton species predominated in the diet of larvae, the Holarctic daphnia, Daphnia galeata, and the Australian calanoid copepod Boeckella symmetrica. This study provides new information regarding the timing, movement and predicted recruitment of native fish species in this river basin that has important implications for lake and river management. [ABSTRACT FROM AUTHOR]

Animals under managed care in zoos and aquariums are ideal surrogate study subjects for endangered species that are difficult to obtain in the wild. We compared the fecal and oral microbiomes of healthy, managed African penguins (Spheniscus demersus) to those of other domestic and wild vertebrate hosts to determine how host identity, diet, and environment shape the penguin microbiome. The African penguin oral microbiome was more similar to that of piscivorous marine mammals, suggesting that diet and a marine environment together play a strong role in shaping the oral microbiome. Conversely, the penguin cloaca/fecal microbiome was more similar to that of other birds, suggesting that host phylogeny plays a significant role in shaping the gut microbiome. Although the penguins were born under managed care, they had a gut microbiome more similar to that of wild bird species compared to domesticated (factory-farmed) birds, suggesting that the managed care environment and diet resemble those experienced by wild birds. Finally, the microbiome composition at external body sites was broadly similar to that of the habitat, suggesting sharing of microbes between animals and their environment. Future studies should link these results to microbial functional capacity and host health, which will help inform conservation efforts. [ABSTRACT FROM AUTHOR]

The uncertainty associated with the impact of a bioinoculant on soil microbial community and, as a consequence, on soil quality, as well as the need to define its persistence, has prompted the demand for an accurate detection and tracking of the presence and the quantification of a target microbial inoculant in soil. Although DNA or RNA-based molecular detection are well established and commonly applied in this regard, alternative ligands such as DNA-aptamers have several advantages over them, such as low cost, ease of modification, ease of immobilisation on lab-on-chip or nanosensors, high stability and not thermolability. In this study, we used a toggle-cell SELEX method to isolate, select and characterise ssDNA (single-strand DNA) aptamers to detect a Bacillus subtilis strain which is being tested as a plant growth promoting rhizobacteria (PGPR) formulation. Two ssDNA aptamers (patenting application n.102022000022590) showed strong affinity and specificity for B. subtilis strains, with values of the kinetic parameters Kd (dissociation constant) in the nanomolar range and Bmax (maximum intensity of binding) around 1. Validation of the suitability of the aptamers was validated on three inoculated soils characterised by different chemical-physical features and in soil from a field trial with the formulated B. subtilis PCM/B 00105 strain. These are considered significant features to monitor B. subtilis strains in soil, practical to optimise bioinoculant application methods, support regulatory processes and foster the shift of agricultural production toward more sustainable cropping systems. Key points: • First DNA aptamers binding a B. subtilis strain included in a bioinoculum formulation. • First DNA aptamer binding B. subtilis in soil. • Aptamer may be a method for microbial inoculant detection in soil. [ABSTRACT FROM AUTHOR]

The diversity and spatial distribution of microscopic invertebrates in the Arctic have yet to be studied in detail. Knowledge of this is especially important in the context of glacier shrinking, one of the most visible environmental consequences of climate change. To understand how time since deglaciation shapes the communities of limno-terrestrial microfauna, we analysed samples of moss collected during the summer of 2021 in forefields of Trygghamna (Svalbard), where glaciers thought to have started to recede at the beginning of the twentieth century. We estimated the taxonomic and trophic composition and abundance of all microfauna groups (with a specific focus on little-known bdelloid rotifers) in two areas, which correspond to the different stages of the glacial retreat. The impact of 14 other environmental parameters (distance from the sea, moisture, moss structural complexity, soil nutrient, and isotopic composition) was considered. Thirty-seven microfauna taxa were found, wherein Dorylaimida nematodes (Dorylaimida, Nematoda) dominated both in frequency (present at all sites) and abundance (50 ± 21% from all individuals). Less prevalent bdelloid rotifers (Bdelloidea, Rotifera) were followed by tardigrades (Tardigrada), which, in contrast to others, were more abundant in the later deglaciated area. In general, environmental parameters explained 81.8% of the microfauna distribution. Time since deglaciation was the most significant factor (9.5%). Among the variables that act at a fine scale, the most important were moisture in the habitat (6%), presence of ground in the samples (4%), and δ15N (4%). The moss structural complexity did not have a significant effect, and neither did most of the variables characterising soil nutrient and isotopic composition. However, some variability was observed for different lower taxa. [ABSTRACT FROM AUTHOR]

Fungi comprise approximately 20% of all eukaryotic species and are connected to virtually all life forms on Earth. Yet, their diversity remains contentious, their distribution elusive, and their conservation neglected. We aim to flip this situation by synthesizing current knowledge. We present a revised estimate of 2–3 million fungal species with a "best estimate" at 2.5 million. To name the unknown >90% of these by the end of this century, we propose recognition of species known only from DNA data and call for large-scale sampling campaigns. We present an updated global map of fungal richness, highlighting tropical and temperate ecoregions of high diversity. We call for further Red List assessments and enhanced management guidelines to aid fungal conservation. Given that fungi play an inseparable role in our lives and in all ecosystems, and considering the fascinating questions remaining to be answered, we argue that fungi constitute the next frontier of biodiversity research. [ABSTRACT FROM AUTHOR]

Host-microbe interactions are ubiquitous and play important roles in host biology, ecology, and evolution. Yet, host-microbe research has focused on inland species, whereas marine hosts and their associated microbes remain largely unexplored, especially in developing countries in the Southern Hemisphere. Here, we review the current knowledge of marine host microbiomes in the Southern Hemisphere. Our results revealed important biases in marine host species sampling for studies conducted in the Southern Hemisphere, where sponges and marine mammals have received the greatest attention. Sponge-associated microbes vary greatly across geographic regions and species. Nevertheless, besides taxonomic heterogeneity, sponge microbiomes have functional consistency, whereas geography and aging are important drivers of marine mammal microbiomes. Seabird and macroalgal microbiomes in the Southern Hemisphere were also common. Most seabird microbiome has focused on feces, whereas macroalgal microbiome has focused on the epibiotic community. Important drivers of seabird fecal microbiome are aging, sex, and species-specific factors. In contrast, host-derived deterministic factors drive the macroalgal epibiotic microbiome, in a process known as "microbial gardening". In turn, marine invertebrates (especially crustaceans) and fish microbiomes have received less attention in the Southern Hemisphere. In general, the predominant approach to study host marine microbiomes has been the sequencing of the 16S rRNA gene. Interestingly, there are some marine holobiont studies (i.e., studies that simultaneously analyze host (e.g., genomics, transcriptomics) and microbiome (e.g., 16S rRNA gene, metagenome) traits), but only in some marine invertebrates and macroalgae from Africa and Australia. Finally, we introduce an ongoing project on the surface microbiome of key species in the Strait of Magellan. This is an international project that will provide novel microbiome information of several species in the Strait of Magellan. In the short-term, the project will improve our knowledge about microbial diversity in the region, while long-term potential benefits include the use of these data to assess host-microbial responses to the Anthropocene derived climate change. [ABSTRACT FROM AUTHOR]

Background: The stapedial artery is an embryonic artery that transiently supplies the cranial vasculature of the human embryo. Postnatal persistence of the stapedial artery may cause conductive hearing loss and pulsatile tinnitus due to its course through the middle ear. We describe a patient with a persistent stapedial artery (PSA) managed by endovascular coil occlusion prior to stapedotomy. Methods: A 48-year-old woman presented with left-sided conductive hearing loss and pulsatile tinnitus. Ten years earlier the patient had undergone explorative tympanoplasty, which was aborted due to a large PSA. Digital subtraction angiography was performed to confirm the anatomy and endovascular occlusion of the proximal PSA was achieved by deployment of coils. Results: The pulsatile tinnitus improved immediately after the procedure. The size of the artery subsequently decreased and surgery could be performed with only a minor intraoperative bleeding. Successful stapedotomy resulted in postoperative normalization of her hearing with some minor residual tinnitus. Conclusion: Endovascular coil occlusion of a PSA is feasible and safe in patients with favorable anatomy and facilitates middle ear surgery. It decreases the size of the artery and minimizes the risk of intraoperative bleeding in patients with a large PSA. The future role of this novel technique in the management of patients with PSA-related conductive hearing loss and pulsatile tinnitus remains to be determined. [ABSTRACT FROM AUTHOR]

Background: Soil nematodes are one of the most important terrestrial faunal groups in Antarctica, as they are a major component of soil micro-food webs. Despite their crucial role in soil processes, knowledge of their species diversity and distribution is still incomplete. Taxonomic studies of Antarctic nematodes are fragmented, which prevents assessment of the degree of endemicity and distribution of the species, as well as other aspects of biogeography. New information: The present study is focused on the nematode fauna of one of the three Antarctic subregions, the Maritime Antarctic and summarises all findings published up to April 2023. A species list that includes 44 species, belonging to 21 genera, 16 families and eight orders is provided. A review of the literature on terrestrial nematodes inhabiting the Maritime Antarctic showed that the sites are unevenly studied. Three islands (Signy, King George and Livingston Islands) revealed highest species richness, probably due to the highest rates of research effort. Most species and four genera (Antarctenchus, Pararhyssocolpus, Amblydorylaimus and Enchodeloides) are endemic, proving that nematode fauna of the Maritime Antarctic is autochthonous and unique. Several groups of islands/sites have been revealed, based on their nematode fauna. The study showed that species with a limited distribution prevailed, while only two species (Plectus antarcticus and Coomansus gerlachei) have been found in more than 50% of the sites. Based on the literature data, details on species localities, microhabitat distribution, plant associations and availability of DNA sequences are provided. [ABSTRACT FROM AUTHOR]

With climate, biodiversity and inequity crises squarely upon us, never has there been a more pressing time to rethink how we conceptualize, understand and manage our relationship with Earth's biodiversity. Here, we describe governance principles of 17 Indigenous Nations from the Northwest Coast of North America used to understand and steward relationships among all components of nature, including humans. We then chart the colonial origins of biodiversity science and use the complex case of sea otter recovery to illuminate how ancestral governance principles can be mobilized to characterize, manage and restore biodiversity in more inclusive, integrative and equitable ways. To enhance environmental sustainability, resilience and social justice amid today's crises, we need to broaden who benefits from and participates in the sciences of biodiversity by expanding the values and methodologies that shape such initiatives. In practice, biodiversity conservation and natural resource management need to shift from centralized, siloed approaches to those that can accommodate plurality in values, objectives, governance systems, legal traditions and ways of knowing. In doing so, developing solutions to our planetary crises becomes a shared responsibility. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'. [ABSTRACT FROM AUTHOR]

Small streams constitute the majority of the water courses in a catchment and have specific characteristics that distinguish them from larger streams and rivers. Despite their small size and frequently remote locations, small streams contribute to ecosystem services that are important for humans. Here, we have identified 27 ecosystem services that small streams provide: seven supporting services, eight regulating services, five provisioning services and seven cultural services. Small streams are especially important for the maintenance of biodiversity, which is the basis of many ecosystem services. Small streams also support ecosystem services provided by larger streams and rivers due to longitudinal connectivity resulting in the downstream transference of energy, water, sediments, nutrients, organic matter and organisms. Small streams are, however, highly vulnerable to disturbances, which can compromise the ecosystem services they supply. We see a global need to effectively protect small streams to safeguard biodiversity and human wellbeing. [ABSTRACT FROM AUTHOR]

Purpose: To present two cases of Internal Carotid Artery (ICA) agenesis and conduct a systematic review to assess for associations with other anomalies and intracranial aneurysms. Methodology: We performed a retrospective review of published cases of patients with ICA agenesis with intercavernous anastomosis in MEDLINE database on August 2022 using search terms "internal carotid artery", "agenesis" and "transcavernous anastomosis". We also included two cases of ICA agenesis with type D collateral that we encountered. Results: Total of 46 studies that included 48 patients and two of our cases resulted in 50 patients. Only 70% of studies reported the location of a collateral vessel of which more than two-thirds were on the floor of sella. More than half of the vessels connected cavernous segments of ICA. A1 segment ipsilateral to the side of ICA agenesis was absent in most of the cases but was not true for all cases. Aneurysm was seen in more than one-quarter of the patients. It can also mimic microadenoma as in prior reported cases as well as in one of our cases. Conclusion: ICA agenesis with type D collateral is a rare anomaly but clinically relevant due to the increased risk of an aneurysm or mimic microadenoma or false alarm for occlusion of ICA but knowledge of this rare variant can help in better management of these patients. [ABSTRACT FROM AUTHOR]

Contamination by zooplankton has to a certain extent limited the large-scale cultivation and industrial exploitation of microalgae. However, systematic research on these predators in microalgal culture is still lacking. The identification of zooplanktonic contaminants derived from microalgal cultures is a basis for conducting related studies. Moreover, knowledge of the ecological distribution of such predators is crucial for avoiding or reducing the risk of biological contamination in the management of large-scale microalgal cultures. Understanding the feeding behaviors of zooplanktonic contaminants contributes to the establishment of targeted prevention strategies and control methods. Early detection is essential to allow prevention and control measures to be implemented in a timely and effective way. Reducing the susceptibility of the cultured microalgae to predators through breeding strains selection, the potential of modern molecular methods, or a synthesis of these approaches will be indispensable to the management of zooplankton contamination. Furthermore, exploring the resource utilization of predators helps to understand this issue comprehensively and to turn hazard into wealth. The genus Poterioochromonas is a typical mixotrophic flagellate and has attracted increasing attention because of the dramatic damage it can inflict on a wide range of microalgal cultures, regardless of the culture system, season, or environment. This review explores our current understanding of the predator Poterioochromonas and the areas where further research is needed, which should stimulate reflection on what we still need to know about these predators from a microalgal culture perspective and how we can utilize them. [ABSTRACT FROM AUTHOR]

Biodiversity surveys of Arctic soil ecosystems are limited. Here, we provide a sequence-based inventory of soil fauna from an Arctic tundra ecosystem near the Canadian High Arctic Research Station in Cambridge Bay, Nunavut. Invertebrate communities were extracted at a vegetated and non-vegetated site in three replicates and inventoried using 18S metabarcode sequencing. A total of 361 amplicon sequence variants (ASV) were identified and assigned to the closest matching taxonomic orders, most of which belonged to the Nematoda and Arthropoda. Vegetated soils showed no significantly higher ASV richness relative to non-vegetated soils although they contained a significantly higher diversity of arthropod taxa including insects, mites, and springtails. Most taxa were found only at a single location and even samples from the same site displayed distinct communities, suggesting that belowground species richness in Arctic tundra habitats is highly heterogeneous. Preserving soil biodiversity in a changing Arctic is essential for Inuit communities who rely on intact tundra ecosystems for their health and wellbeing. [ABSTRACT FROM AUTHOR]

This work studied the formation of aggregates used for wastewater treatment in high-rate algal ponds (HRAP). For this, the establishment of microalgae-bacteria aggregates in these systems was evaluated, considering strategies for the inoculation and start-up. Two HRAP were operated in parallel, at first in batch mode and then in continuous flow. The wastewater treatment was efficient, with removal rates around 80% for COD and N-ammoniacal. Volatile suspended solids and chlorophyll for the culture grew continuously reached a concentration of 548 ± 11 mg L−1 and 7.8 mg L−1, respectively. Larger photogranules were observed when the system was placed in a continuous regime. The protein fraction of extracellular polymeric substances was identified as a determinant in photogranules formation. During the continuous regime, more than 50% of the biomass was higher than 0.2 mm, flocculation efficiency of 78 ± 6%, and the volumetric sludge index of 32 ± 5 mL g−1. The genetic sequencing showed the growth of cyanobacteria in the aggregate and the presence of microalgae from the chlorophytes and diatoms groups in the final biomass. [ABSTRACT FROM AUTHOR]

While DNA barcodes are increasingly provided in descriptions of new species, the whole mitochondrial and nuclear genomes are still rarely included. This is unfortunate because whole genome sequencing of holotypes allows perpetual genetic characterization of the most representative specimen for a given species. Thus, de novo genomes are invaluable additional diagnostic characters in species descriptions, provided the structural integrity of the holotype specimens remains intact. Here, we used a minimally invasive method to extract DNA of the type specimen of the recently described caddisfly species Silvatares holzenthali Rázuri-Gonzales, Ngera & Pauls, 2022 (Trichoptera: Pisuliidae) from the Democratic Republic of the Congo. A low-cost next generation sequencing strategy was used to generate the complete mitochondrial and draft nuclear genome of the holotype. The data in its current form is an important extension to the morphological species description and valuable for phylogenomic studies. [ABSTRACT FROM AUTHOR]

The eusirid amphipod Rhachotropis aculeata (Lepechin, 1780) is a boreal species distributed around the Arctic Ocean as well as in high-latitude areas of the North Atlantic and North Pacific Oceans. This is a considerably wide distribution for an amphipod species with no larval stage, implying the possibility that genetic divergence may occur among each population of the species. However, this has not been detailed since there has been no genetic data obtained from Pacific populations. Recently, R. aculeata was collected from the north of Wakasa Bay, Sea of Japan, representing the first specimen-based Japanese record of this species, as well as the southernmost record in the Pacific Ocean. We obtained genetic data from the R. aculeata specimens and subsequently constructed a phylogenetic tree and haplotype network. This included samples from Arctic, Atlantic, and Pacific populations, in order to study the phylogeography of the species. Our analyses indicate a relatively strong genetic divergence of the species between the Pacific and the other populations. [ABSTRACT FROM AUTHOR]

Due to the increasing challenge of meeting human demands for metals from land-based resources, interest in extracting mineral ores from the deep sea has gained momentum in recent years. Targeted mining of deep-seabed minerals could have adverse effects on the associated ecosystems, but knowledge on the biological communities found there, their structure and functions is still limited. The focus of this study is to provide an overview on isopod crustaceans from the Clarion Clipperton Fracture Zone (CCFZ), an area well-known for its abundance of high-grade polymetallic nodules. Isopods generally comprise an important part of the macrofaunal communities of soft deep-sea sediments and indeed are one of the most dominant macrobenthic groups in the CCFZ. In this review, we have compiled all available data and information on isopod diversity and distribution in the CCFZ in a hybrid manner, which includes published data from the literature as well as the analysis of previously unpublished sources and newly collected data. Although isopods are one of the more prevalent and better-known groups of the CCFZ fauna, this study shows that it is still remarkably difficult to obtain a clear perception of isopod diversity and distribution, as well as the factors that could be responsible for the observed patterns. In many places, knowledge remains incomplete, which is largely due to the low sampling and taxonomic effort, non-standardised sample protocols and the limited taxonomic inter-calibration between studies. The latter is pivotal due to the high proportion of undescribed and presumably new species that typically occur there. An important starting point would therefore be to increase sampling effort and its spatial and temporal coverage in a standardised way, to intensify (integrative) taxonomic work as well as to facilitate sample and data exchange between scientists and contractors. These are fundamental requirements to improve our understanding of the biodiversity of isopods, but also of other faunal groups, in the CCFZ, before mining operations begin. [ABSTRACT FROM AUTHOR]