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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. [ABSTRACT FROM AUTHOR]

Global environmental change drives diversity loss and shifts in community structure. A key challenge is to better understand the impacts on ecosystem function and to connect species and trait diversity of assemblages with ecosystem properties that are in turn linked to ecosystem functioning. Here we quantify shifts in species composition and trait diversity associated with ocean acidification (OA) by using field measurements at marine CO2 vent systems spanning four reef habitats across different depths in a temperate coastal ecosystem. We find that both species and trait diversity decreased, and that ecosystem properties (understood as the interplay between species, traits, and ecosystem function) shifted with acidification. Furthermore, shifts in trait categories such as autotrophs, filter feeders, herbivores, and habitat‐forming species were habitat‐specific, indicating that OA may produce divergent responses across habitats and depths. Combined, these findings reveal the importance of connecting species and trait diversity of marine benthic habitats with key ecosystem properties to anticipate the impacts of global environmental change. Our results also generate new insights on the predicted general and habitat‐specific ecological consequences of OA. [ABSTRACT FROM AUTHOR]

This article presents the findings of a study on tropical paleobiology and its implications for understanding biodiversity in the past. Contrary to the prevailing belief that tropical warming reduces biodiversity, the study reveals that biodiversity during a warmer period in the past was actually higher than present-day biodiversity. The authors suggest that sampling bias and the presence of the Amazon River may have influenced these findings, and they also consider the possibility that slightly elevated temperatures during the past period promoted greater diversity. The article also discusses the potential factors contributing to the decline in species diversity in tropical marine ecosystems since the Last Interglacial (LIG) period, including the role of humans. However, the overall reduction in diversity cannot be solely attributed to human impact. The article emphasizes the need for a better understanding of historical changes and ecosystem dynamics in tropical areas to fully comprehend the dynamics of biodiversity in these regions. [Extracted from the article]

Simple Summary: The French Polynesian islands represent a unique insular system in the Pacific Ocean. Previous surveys of the marine flora of French Polynesia were mostly established on traditional morphology-based taxonomy. DNA barcoding allowed us to provide a major revision of French Polynesian marine flora, with an updated total of 702 species from French Polynesia, including 119 species of Chlorophyta, 169 Cyanobacteria, 92 Ochrophyta, 320 Rhodophyta, and 2 species of seagrasses (Alismatales)—nearly a two-fold increase from previous estimates. In addition to improving and refining our knowledge of French Polynesian marine flora, this study also provides a valuable DNA barcode reference library for identification purposes and future taxonomic and conservation studies. A significant part of the diversity uncovered corresponds to unidentified lineages, which will need careful taxonomic examination. Located in the heart of the South Pacific Ocean, the French Polynesian islands represent a remarkable setting for biological colonization and diversification, because of their isolation. Our knowledge of this region's biodiversity is nevertheless still incomplete for many groups of organisms. In the late 1990s and 2000s, a series of publications provided the first checklists of French Polynesian marine algae, including the Chlorophyta, Rhodophyta, Ochrophyta, and Cyanobacteria, established mostly on traditional morphology-based taxonomy. We initiated a project to systematically DNA barcode the marine flora of French Polynesia. Based on a large collection of ~2452 specimens, made between 2014 and 2023, across the five French Polynesian archipelagos, we re-assessed the marine floral species diversity (Alismatales, Cyanobacteria, Rhodophyta, Ochrophyta, Chlorophyta) using DNA barcoding in concert with morphology-based classification. We provide here a major revision of French Polynesian marine flora, with an updated listing of 702 species including 119 Chlorophyta, 169 Cyanobacteria, 92 Ochrophyta, 320 Rhodophyta, and 2 seagrass species—nearly a two-fold increase from previous estimates. This study significantly improves our knowledge of French Polynesian marine diversity and provides a valuable DNA barcode reference library for identification purposes and future taxonomic and conservation studies. A significant part of the diversity uncovered from French Polynesia corresponds to unidentified lineages, which will require careful future taxonomic investigation. [ABSTRACT FROM AUTHOR]

The ocean is one of the most extensive ecosystems on Earth and can absorb large amounts of carbon dioxide. Changes in seawater carbon dioxide concentrations are one of the most important factors affecting marine ecosystems. Excess carbon dioxide can lead to ocean acidification, threatening the stability of marine ecosystems and species diversity. Dissolved carbon dioxide detection in seawater has great scientific significance. Conducting online monitoring of seawater carbon dioxide can help to understand the health status of marine ecosystems and to protect marine ecosystems. Current seawater detection equipment is large and costly. This study designed a low-cost infrared carbon dioxide detection system based on molecular theory. Using the HITRAN database, the absorption spectra and coefficients of carbon dioxide molecules under different conditions were calculated and derived, and a wavelength of 2361 cm−1 was selected as the measurement channel for carbon dioxide. In addition, considering the interference effect of direct light, an infrared post-splitting method was proposed to eliminate the interference of light and improve the detection accuracy of the system. The system was designed for the online monitoring of carbon dioxide in seawater, including a peristaltic pump to accelerate gas–liquid separation, an optical path structure, and carbon dioxide concentration inversion. The experimental results showed that the standard deviation of the gas test is 3.05, the standard deviation of the seawater test is 6.04, and the error range is within 20 ppm. The system can be flexibly deployed and has good stability and portability, which can meet the needs of the online monitoring of seawater carbon dioxide concentration. [ABSTRACT FROM AUTHOR]

Simple Summary: An increasing number of different habitats leads to an increasing number of species and has been considered a key driver for biodiversity. However, there is no common understanding on how to measure habitat diversity. In this study, we tested a newly proposed measure of substrate heterogeneity by classifying changes on the seafloor with underwater video imaging. This analysis showed that the presence of small patches of different soft sediment types was associated with elevated species richness and a higher rate of occurrence of rare species. Many studies show that habitat complexity or habitat diversity plays a major role in biodiversity throughout different spatial scales: as structural heterogeneity increases, so does the number of available (micro-) habitats for the potential species inventory. The capability of housing species (even rare species) increases rapidly with increasing habitat heterogeneity. However, habitat complexity is not easy to measure in marine sublittoral sediments. In our study, we came up with a proposal to estimate sublittoral benthic habitat complexity using standard underwater video techniques. This tool was subsequently used to investigate the effect of habitat complexity on species richness in comparison to other environmental parameters in a marine protected area situated in the Fehmarn Belt, a narrow strait in the southwestern Baltic Sea. Our results show that species richness is significantly higher in heterogeneous substrates throughout all considered sediment types. Congruently, the presence of rare species increases with structural complexity. Our findings highlight the importance of the availability of microhabitats for benthic biodiversity as well as of the study area for regional ecosystem functioning. [ABSTRACT FROM AUTHOR]

The article showcases a photo competition called "Open FotoSub El Hierro" that celebrates underwater photography in the waters around El Hierro, Canary Islands, Spain. It features a diverse range of marine species found in the region, including fish such as Aguja (Belone belone), Morena negra (Muraena helena), Fula blanca (Chromis limbata), and many others. It also provides insights into the backgrounds and achievements of the winners in their respective underwater photography careers.

Background: Evolutionary divergence and speciation often occur at a slower rate in the marine realm due to the higher potential for long-distance reproductive interaction through larval dispersal. One common evolutionary pattern in the Indo-Pacific, is divergence of populations and species at the peripheries of widely-distributed organisms. However, the evolutionary and demographic histories of such divergence are yet to be well understood. Here we address these issues by coupling genome-wide SNP data with mitochondrial DNA sequences to test the patterns of genetic divergence and possible secondary contact among geographically distant populations of the highly valuable spiny lobster Panulirus homarus species complex, distributed widely through the Indo-Pacific, from South Africa to the Marquesas Islands. Result: After stringent filtering, 2020 SNPs were used for population genetic and demographic analyses, revealing strong regional structure (FST = 0.148, P < 0001), superficially in accordance with previous analyses. However, detailed demographic analyses supported a much more complex evolutionary history of these populations, including a hybrid origin of a North-West Indian Ocean (NWIO) population, which has previously been discriminated morphologically, but not genetically. The best-supported demographic models suggested that the current genetic relationships among populations were due to a complex series of past divergences followed by asymmetric migration in more recent times. Conclusion: Overall, this study suggests that alternating periods of marine divergence and gene flow have driven the current genetic patterns observed in this lobster and may help explain the observed wider patterns of marine species diversity in the Indo-Pacific. [ABSTRACT FROM AUTHOR]

(d) The contacted fish exhibited severely attenuated and flattened epithelium (yellow arrow) and alteration in their pigment layer on the dorsal skin (black arrow, H&E stain) gl Field observations suggested that the sea anemone may be the cause of the acute death of the snubnose pompano and permit. Keywords: broodstock; mortality; permit; red drum; snubnose pompano EN broodstock mortality permit red drum snubnose pompano 1799 1803 5 10/14/22 20221101 NES 221101 In February 2022, unusual acute mortalities were observed in snubnose pompano ( I Trachinotus blochii i ) and permit ( I T. falcatus i ) broodstock held in sea cages in Nha Phu lagoon, Khanh Hoa, Vietnam. Thirty fish ( I n i = 30) were divided evenly among three groups: high density (25 sea anemones per 100 ml), low density (5 sea anemones per 100 ml) and control (no sea anemone). [Extracted from the article]

Introduction: Collagen has been obtained mainly from bovine and porcine species for use in the food, cosmetic, biomedical, and pharmaceutical industries. However, several conditions have caused that, in recent years, these productions have started to be developed from marine species. Objective: To present an updated overview of the status of collagen isolation from fish byproducts. Materials and Methods: A bibliographic search was done based on results published up to the year 2020. Results and Discussion: Due to the high demand for collagen, there is an urgent need to find sustainable and cheaper sources for its production. Marine biomass is becoming a more attractive source of collagen. There are different methods of isolation of this product of which enzymatic hydrolysis is the most promising. Its applications are varied and new fields of use in various industries, as well as in medicine and biotechnology, are becoming known. Conclusions: The wide variety of applications of collagen and its important roles in the future of tissue engineering make it a key biopolymer for human health and wellness. [ABSTRACT FROM AUTHOR]

This report describe the first application of environmental DNA‐metabarcoding approach for the assessment of fish species diversity in two marine protected areas of the North Sea: the Doggerbank and the Sylt Outer Reef. We collected 64 water samples and detected 24 fish species. We discuss qualitative differences between MPAs and compare the results with those obtained from bottom‐trawl surveys in the same areas. We found three additional species to those documented in the same year with trawls, including the critically endangered European eel. [ABSTRACT FROM AUTHOR]

Over the last decades, the species distribution model (SDM) has become an essential tool for studying the potential effects of climate change on species distribution. In this study, an ensemble SDM was developed to predict the changes in species distribution of swimming crab Portunus trituberculatus across different seasons in the future (2050s and 2100s) under the climate scenarios of Representative Concentration Pathway (RCP)4.5 and RCP8.5. Results of the ensemble SDM indicate that the distribution of this species will move northward and exhibit evident seasonal variations. Among the four seasons, the suitable habitat for this species will be significantly reduced in summer, with loss rates ranging from 45.23% (RCP4.5) to 88.26% (RCP.8.5) by the 2100s. The loss of habitat will mostly occur in the East China Sea and the southern part of the Yellow Sea, while a slight increase in habitat will occur in the northern part of the Bohai Sea. These findings provide an information forecast for this species in the future. Such forecast will be helpful in improving fishery management under climate change. [ABSTRACT FROM AUTHOR]

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community composition at such geographic scales remains unknown. Using standardized experiments that spanned 115° of latitude, at 36 nearshore sites along both coasts of the Americas, we found that marine predators have both higher consumption rates and consistently stronger impacts on biomass and species composition of marine invertebrate communities in warmer tropical waters, likely owing to fish predators. Our results provide robust support for a temperature-dependent gradient in interaction strength and have potential implications for how marine ecosystems will respond to ocean warming. [ABSTRACT FROM AUTHOR]

The study of sister species that occur in parapatry around biogeographic transition zones can help understand the evolutionary processes that underlie the changes in species composition across biogeographic transition zones. The South Eastern Pacific (SEP) coast is a highly productive coastal system that exhibits a broad biogeographic transition zone around 30–35°S. Here, we present a comparative genome‐wide analysis of the sister species Scurria viridula and Scurria zebrina, that occur in parapatry and whose poleward and equatorward range edges intersect in the 30–35°S SEP biogeographic transition zone. We sampled 118 specimens sourced from nine sites from Tocopilla (22°S) to Chiloé (41°S) including one site where both species overlap and analyzed over 8000 biallelic single nucleotide polymorphisms. We found evidence of hybridization between these species in the contact zone and found significant but contrasting population structures for both species. Our results indicate that the genetic structure in S. viridula, which is currently expanding its range poleward, follows a simple isolation by distance model with no traces of natural selection (no evidence of outlier loci). In contrast, S. zebrina, which has its equatorward range edge at the transition zone, displayed a pronounced genetic break approximately at 32–34°S, along a region of marked environmental heterogeneity in association with a semi‐permanent coastal upwelling regime. For S. zebrina we also found 43 outlier loci associated with this genetic break, with a significant proportion of them clustering in a single linkage group. This marked difference in the presence of outlier loci between species suggests that they could be responding differently to local environmental challenges found at their overlapping geographic range edges, thus providing important new insights about genomic changes around biogeographic transition zones in sister species and the forces that shape genetic diversity in intertidal marine species. [ABSTRACT FROM AUTHOR]

The growing global demand for sustainable and environmentally friendly energy has stimulated the rapid adoption of renewable offshore energy. However, infrastructure needed for green energy production ironically impacts upon marine species and biodiversity. Consequently, this positional review paper seeks to comprehensively synthesise the prevailing body of knowledge on the impact of offshore energy development on a broad range of marine species. An interpretivist philosophical stance and inductive reasoning was adopted using scientometric analysis to conduct a rich synthesis of extant literature. From an operational perspective, the Scopus database was utilised to search for key terms on the phenomena under investigation and using the VoS Viewer software for the identification of trends using scientometric maps. The analysis reveals that research in this area of science has increased significantly over the last decade but private sector involvement is conspicuous by its absence. Primary concerns among the research community include the impact of energy development on the abundance of species, pollution and biodiversity behaviour and migration. At present, researchers have extensively focused on the impact of offshore wind farms on fish and marine mammals. However, the literature reveals no significant long-term impact upon energy development on most marine species albeit, short-term interference has raised concerns (from sound, disruption of navigation and foraging patterns, and damage of habitat). To minimise short term disruption, researchers have recommended the use of acoustic deterrence during construction, enforcement of protected areas and continued research. [ABSTRACT FROM AUTHOR]

• Combining eDNA and trawl data increases the detected biodiversity. • Good reference databases are of vital importance for correct taxonomic classification. • We advocate that a combined sampling effort is a good strategy for future monitoring of biodiversity in the Arctic including the Barents Sea. Managing natural resources in a sustainable manner requires understanding the complexity of ecosystems and the species that are associated with the different parts of the ecosystem. Much of this knowledge is derived from traditional sampling methods (e.g., different types of trawls). The analysis of environmental DNA (eDNA) can provide increased knowledge, complementary to the traditional methods. In the present pilot study, we sampled eDNA from two geographical areas, north and west of Svalbard (NWS) and in the southwestern Barents Sea (SWBS). The combination of trawling, visual identification of mammals and eDNA collection facilitated a robust analysis of fish and marine mammal diversity and species composition. Through 12S MiFish metabarcoding of the eDNA samples, we found that incorporating eDNA data provided an additional level of information on both the diversity of fish and marine mammals in the study areas. By adding eDNA data to the trawl data, we found that richness increased from 32 to 49 fish taxa. Significant differences in diversity and composition of the fish communities were detected by eDNA between the two study areas. Considering degradation and dilution factors it is postulated that the results represent resident species to the Barents Sea and that long -transported DNA from other areas are less likely. [ABSTRACT FROM AUTHOR]

Marine ecosystems in urban coastal areas are exposed to many risks due to human activity. Thus, long-term and continuous monitoring of zooplankton diversity is necessary. High-throughput DNA metabarcoding has gained recognition as an efficient and highly sensitive approach to accurately describing the species diversity of marine zooplankton assemblages. In this study, we collected 30 zooplankton samples at about 2-week intervals for 1 year. Zooplankton diversity showing a typical four season pattern. Of the "total" and "common" zooplankton, we assigned 267 and 64 taxa. The cluster structure and seasonal diversity pattern were rough when only the "common" zooplankton was used. Our study examined how to maximize the benefits of metabarcoding for monitoring zooplankton diversity in urban coastal areas. The results suggest that to take full advantage of metabarcoding when monitoring a zooplankton community, it is necessary to carefully investigate potential ecosystem threats (non-indigenous species) through sufficient curation rather than disregarding low-abundance operational taxonomic units. [ABSTRACT FROM AUTHOR]

Alongside collective mismanagement, illegal, unreported and unregulated ('IUU') fishing practices pose a serious threat to marine species and ecosystems around the globe. Drastically reducing IUU fishing must form part of global efforts to promote more responsible and just exploitation of marine living resources. While attention on tackling IUU fishing has increased over the past two decades, progress toward its elimination remains slow, largely due to the inherently transboundary nature of IUU practices and the practical limitations of flag and coastal state jurisdiction. This article argues that port states can and should play a central role in international efforts to tackle IUU fishing. It considers the steps port states can lawfully take to remove IUU practices from global supply chains and explores the conditions and limitations general international law, the law of the sea and international trade law impose on various port state measures. While port state control raises significant issues of jurisdictional competence, substantive and procedural fairness, and multilateral coordination, it is shown that port state measures are both a feasible and defensible means of addressing IUU practices. By exploring the conditions that attach to the design, adoption and implementation of port state measures, the article resolves key debates concerning their lawfulness, thus allowing policymakers, practitioners and officials to renew their attention on developing the political will and technical capabilities necessary for such measures to play an effective and appropriate role in closing regulatory and enforcement gaps in conservation and management regimes. [ABSTRACT FROM AUTHOR]

Alongside collective mismanagement, illegal, unreported and unregulated (‘IUU’) fishing practices pose a serious threat to marine species and ecosystems around the globe. Drastically reducing IUU fishing must form part of global efforts to promote more responsible and just exploitation of marine living resources. While attention on tackling IUU fishing has increased over the past two decades, progress toward its elimination remains slow, largely due to the inherently transboundary nature of IUU practices and the practical limitations of flag and coastal state jurisdiction. This article argues that port states can and should play a central role in international efforts to tackle IUU fishing. It considers the steps port states can lawfully take to remove IUU practices from global supply chains and explores the conditions and limitations general international law, the law of the sea and international trade law impose on various port state measures. While port state control raises significant issues of jurisdictional competence, substantive and procedural fairness, and multilateral coordination, it is shown that port state measures are both a feasible and defensible means of addressing IUU practices. By exploring the conditions that attach to the design, adoption and implementation of port state measures, the article resolves key debates concerning their lawfulness, thus allowing policymakers, practitioners and officials to renew their attention on developing the political will and technical capabilities necessary for such measures to play an effective and appropriate role in closing regulatory and enforcement gaps in conservation and management regimes. [ABSTRACT FROM AUTHOR]

The checklist of the marine Brachyura from the Iraqi coast has been analyzed and presently it comprises 29 species. The Pilumnidae, Leucosiidae, Camptandriidae, and Macrophthalmidae are the most diverse families in the northwestern Persian- Arabian Gulf. Specimens of Phalangipus persicus Griffin, 1973 have been collected from the northwest of the Persian- Arabian Gulf, Iraq, at the Fao region in July 2019. This species is widely distributed in the Persian-Arabian Gulf, Iran, Saudi Arabia, and UAE; however, it is recorded for the first time from the Iraqi coasts. [ABSTRACT FROM AUTHOR]

A new species of Grateloupia from Wenzhou Nanji Island in Zhejiang province, China, was illustrated based on morphological observation, early development, life history and rbcL gene sequence analysis, and named Grateloupia oligoclora H.W.Wang & Y.Bian sp. nov. The morphological features of this new species can be summarized as upright thalli, solitary or cespitose, dark red in colour, cartilaginous and mucilaginous in texture. The margins of the thalli were smooth, without lateral branches, proliferations, or branched, dichotomously branched or with 3–5 irregular rod-shaped branches. The thalli were consisted of cortex cells (6–9 cell layers) and medulla. The cystocarps were spherical and appeared to be speckled from the surface of the thalli. The carpogonial branch ampullae and auxiliary cell branch were typical Grateloupia-type. During the cruciate dividing of tetrasporangia, some dyads showed asynchronous phenomenon. Type of spore development and life history were typical mediate discal type and isomorphic alternation of generations. Phylogenetic analysis based on rbcL sequence indicated that the new taxon formed an independent clade from other Grateloupia species, and this clade was sister to G. subpectinata Holmes with high interspecific divergence 12 bp (1%), supporting its specific status. Accordingly, G. oligoclora H.W.Wang & Y.Bian sp. nov is proposed as a new species of Grateloupia. This study provides new resource and species diversity of marine Rhodophyta in China. [ABSTRACT FROM AUTHOR]

Changes in the functional structures of communities are rarely examined along multiple large‐scale environmental gradients. Here, we describe patterns in functional beta diversity for New Zealand marine fishes versus depth and latitude, including broad‐scale delineation of functional bioregions. We derived eight functional traits related to food acquisition and locomotion and calculated complementary indices of functional beta diversity for 144 species of marine ray‐finned fishes occurring along large‐scale depth (50–1200 m) and latitudinal gradients (29°–51°S) in the New Zealand Exclusive Economic Zone. We focused on a suite of morphological traits calculated directly from in situ Baited Remote Underwater Stereo‐Video (stereo‐BRUV) footage and museum specimens. We found that functional changes were primarily structured by depth followed by latitude, and that latitudinal functional turnover decreased with increasing depth. Functional turnover among cells increased with increasing depth distance, but this relationship plateaued for greater depth distances (>750 m). In contrast, functional turnover did not change significantly with increasing latitudinal distance at 700–1200 m depths. Shallow functional bioregions (50–100 m) were distinct at different latitudes, whereas deeper bioregions extended across broad latitudinal ranges. Fishes in shallow depths had a body shape conducive to efficient propulsion, while fishes in deeper depths were more elongated, enabling slow, energy‐efficient locomotion, and had large eyes to enhance vision. Environmental filtering may be a primary driver of broad‐scale patterns of functional beta diversity in the deep sea. Greater environmental homogeneity may lead to greater functional homogeneity across latitudinal gradients at deeper depths (700–1200 m). We suggest that communities living at depth may follow a 'functional village hypothesis', whereby similar key functional niches in fish communities may be maintained over large spatial scales. [ABSTRACT FROM AUTHOR]

Variation in both inter‐ and intraspecific traits affects community dynamics, yet we know little regarding the relative importance of external environmental filters versus internal biotic interactions that shape the functional space of communities along broad‐scale environmental gradients, such as latitude, elevation, or depth. We examined changes in several key aspects of functional alpha diversity for marine fishes along depth and latitude gradients by quantifying intra‐ and interspecific richness, dispersion, and regularity in functional trait space. We derived eight functional traits related to food acquisition and locomotion and calculated seven complementary indices of functional diversity for 144 species of marine ray‐finned fishes along large‐scale depth (50–1200 m) and latitudinal gradients (29°–51° S) in New Zealand waters. Traits were derived from morphological measurements taken directly from footage obtained using Baited Remote Underwater Stereo‐Video systems and museum specimens. We partitioned functional variation into intra‐ and interspecific components for the first time using a PERMANOVA approach. We also implemented two tree‐based diversity metrics in a functional distance‐based context for the first time: namely, the variance in pairwise functional distance and the variance in nearest neighbor distance. Functional alpha diversity increased with increasing depth and decreased with increasing latitude. More specifically, the dispersion and mean nearest neighbor distances among species in trait space and intraspecific trait variability all increased with depth, whereas functional hypervolume (richness) was stable across depth. In contrast, functional hypervolume, dispersion, and regularity indices all decreased with increasing latitude; however, intraspecific trait variation increased with latitude, suggesting that intraspecific trait variability becomes increasingly important at higher latitudes. These results suggest that competition within and among species are key processes shaping functional multidimensional space for fishes in the deep sea. Increasing morphological dissimilarity with increasing depth may facilitate niche partitioning to promote coexistence, whereas abiotic filtering may be the dominant process structuring communities with increasing latitude. [ABSTRACT FROM AUTHOR]

A habitat model has been widely used to manage marine species and analyze relationship between species distribution and environmental factors. The predictive skill in habitat model depends on whether the models include appropriate explanatory variables. Due to limited habitat range, low density, and low detection rate, the number of zero catches could be very large even in favorable habitats. Excessive zeroes will increase the bias and uncertainty in estimation of habitat. Therefore, appropriate explanatory variables need to be chosen first to prevent underestimate or overestimate species abundance in habitat models. In addition, biotic variables such as prey data and spatial autocovariate (SAC) of target species are often ignored in species distribution models. Therefore, we evaluated the effects of input variables on the performance of generalized additive models (GAMs) under excessive zero catch (>70%). Five types of input variables were selected, i.e., (1) abiotic variables, (2) abiotic and biotic variables, (3) abiotic variables and SAC, (4) abiotic, biotic variables and SAC, and (5) principal component analysis (PCA) based abiotic and biotic variables and SAC. Belanger's croaker Johnius belangerii is one of the dominant demersal fish in Haizhou Bay, with a large number of zero catches, thus was used for the case study. Results show that the PCA-based GAM incorporated with abiotic and biotic variables and SAC was the most appropriate model to quantify the spatial distribution of the croaker. Biotic variables and SAC were important and should be incorporated as one of the drivers to predict species distribution. Our study suggests that the process of input variables is critical to habitat modelling, which could improve the performance of habitat models and enhance our understanding of the habitat suitability of target species. [ABSTRACT FROM AUTHOR]

Aliger gigas is an economically important and vulnerable marine species. We present a new mitogenome of A. gigas from the Mexican Caribbean and use the eight publicly available Strombidae mitogenomes to analyze intra- and interspecific variation. We present the most complete phylogenomic understanding of Hypsogastropoda to date (17 superfamilies, 39 families, 85 genera, 109 species) to revisit the phylogenetic position of the Stromboidea and evaluate divergence times throughout the phylogeny. The A. gigas mitogenome comprises 15,460 bp including 13 PCGs, 22 tRNAs, and two rRNAs. Nucleotide diversity suggested divergence between the Mexican and Colombian lineages of A. gigas. Interspecific divergence showed high differentiation among Strombidae species and demonstrated a close relationship between A. gigas and Strombus pugilis, between Lambis lambis and Harpago chiragra, and among Tridentarius dentatus/Laevistrombus canarium/Ministrombus variabilis. At the intraspecific level, the gene showing the highest differentiation is ATP8 and the lowest is NAD4L, whereas at the interspecific level the NAD genes show the highest variation and the COX genes the lowest. Phylogenomic analyses confirm that Stromboidea belongs in the non-Latrogastropoda clade and includes Xenophoridea. The phylogenomic position of other superfamilies, including those of previously uncertain affiliation, is also discussed. Finally, our data indicated that Stromboidea diverged into two principal clades in the early Cretaceous while Strombidae diversified in the Paleocene, and lineage diversification within A. gigas took place in the Pleistocene. [ABSTRACT FROM AUTHOR]

Characterization of species diversity of zooplankton is key to understanding, assessing, and predicting the function and future of pelagic ecosystems throughout the global ocean. The marine zooplankton assemblage, including only metazoans, is highly diverse and taxonomically complex, with an estimated ~28,000 species of 41 major taxonomic groups. This review provides a comprehensive summary of DNA sequences for the barcode region of mitochondrial cytochrome oxidase I (COI) for identified specimens. The foundation of this summary is the MetaZooGene Barcode Atlas and Database (MZGdb), a new open-access data and metadata portal that is linked to NCBI GenBank and BOLD data repositories. The MZGdb provides enhanced quality control and tools for assembling COI reference sequence databases that are specific to selected taxonomic groups and/or ocean regions, with associated metadata (e.g., collection georeferencing, verification of species identification, molecular protocols), and tools for statistical analysis, mapping, and visualization. To date, over 150,000 COI sequences for ~ 5600 described species of marine metazoan plankton (including holo- and meroplankton) are available via the MZGdb portal. This review uses the MZGdb as a resource for summaries of COI barcode data and metadata for important taxonomic groups of marine zooplankton and selected regions, including the North Atlantic, Arctic, North Pacific, and Southern Oceans. The MZGdb is designed to provide a foundation for analysis of species diversity of marine zooplankton based on DNA barcoding and metabarcoding for assessment of marine ecosystems and rapid detection of the impacts of climate change. [ABSTRACT FROM AUTHOR]

The timing of reproduction influences key evolutionary and ecological processes in wild populations. Variation in reproductive timing may be an especially important evolutionary driver in the marine environment, where the high mobility of many species and few physical barriers to migration provide limited opportunities for spatial divergence to arise. Using genomic data collected from spawning aggregations of Pacific herring (Clupea pallasii) across 1600 km of coastline, we show that reproductive timing drives population structure in these pelagic fish. Within a specific spawning season, we observed isolation by distance, indicating that gene flow is also geographically limited over our study area. These results emphasize the importance of considering both seasonal and spatial variation in spawning when delineating management units for herring. On several chromosomes, we detected linkage disequilibrium extending over multiple Mb, suggesting the presence of chromosomal rearrangements. Spawning phenology was highly correlated with polymorphisms in several genes, in particular SYNE2, which influences the development of retinal photoreceptors in vertebrates. SYNE2 is probably within a chromosomal rearrangement in Pacific herring and is also associated with spawn timing in Atlantic herring (Clupea harengus). The observed genetic diversity probably underlies resource waves provided by spawning herring. Given the ecological, economic and cultural significance of herring, our results support that conserving intraspecific genetic diversity is important for maintaining current and future ecosystem processes. [ABSTRACT FROM AUTHOR]

Siniperca chuatsi and Siniperca kneri are two economically important freshwater fishes endemic to East Asia. Recently, some Siniperca specimens collected from Lake Poyang and Lake Dongting in the middle reaches of the Yangtze River couldn't be clearly identified as they showed intermediate morphological characteristics between S. chuatsi and S. kneri, and some inter-species hybrids were detected by microsatellite loci. To further verify genetic composition of these intermediate individuals, and determine the prevalence and degree of introgression between the two Siniperca species, a large set of high-quality, independent, diagnostic genetic markers were necessarily required. Based on enrichment and sequencing of target genes in sinipercid fishes, 463 loci (FST = 1) between S. chuatsi and S. kneri were selected and verified for species diagnosis. A total of 349 loci with 458 diagnostic SNPs were identified for discriminating S. chuatsi and S. kneri. From those markers, 224 diagnostic SNPs (only one SNP per locus) were selected to identify and categorize 48 specimens with intermediate morphological characters. The results showed that there were 8 specimens identified as hybrids, 8 specimens as S. chuatsi and 32 specimens as S. kneri. NEWHYBRIDS analysis showed that the hybrid offsprings were composed of the first-generation hybrid (2 individuals), first-generation backcross (1 individual), second-generation backcross (1 individual) and fourth-generation backcross (4 individuals), and the backcrossing could happen to both S. chuatsi and S. kneri. These hybrids could occur naturally, or escaped from farmed fish, due to extensive artificial breeding practice in these regions. However, the origin of the introgressive hybridization can't be easily traced. Therefore, some measures for protecting genetic resource of Siniperca speies in the Yangtze River should be enforced, such as assessing genetic background of the cultured stocks, reducing the escapement from farmed fish, and monitoring the trend of introgressive hybridization between Siniperca species in the future. [ABSTRACT FROM AUTHOR]

An accurate identification of species and communities is a prerequisite for analysing and recording biodiversity and community shifts. In the context of marine biodiversity conservation and management, this review outlines past, present and forward-looking perspectives on identifying and recording planktonic diversity by illustrating the transition from traditional species identification based on morphological diagnostic characters to full molecular genetic identification of marine assemblages. In this process, the article presents the methodological advancements by discussing progress and critical aspects of the crossover from traditional to novel and future molecular genetic identifications and it outlines the advantages of integrative approaches using the strengths of both morphological and molecular techniques to identify species and assemblages. We demonstrate this process of identifying and recording marine biodiversity on pelagic copepods as model taxon. Copepods are known for their high taxonomic and ecological diversity and comprise a huge variety of behaviours, forms and life histories, making them a highly interesting and well-studied group in terms of biodiversity and ecosystem functioning. Furthermore, their short life cycles and rapid responses to changing environments make them good indicators and core research components for ecosystem health and status in the light of environmental change. This article is part of the theme issue 'Integrative research perspectives on marine conservation'. [ABSTRACT FROM AUTHOR]

Trophic niche and diet comparisons among closely sympatric marine species are important to understand complex food webs, particularly in regions most affected by climate change. Using stable isotope analyses, all ontogenetic stages of three sympatric species of Arctic cephalopods (genus Rossia) were studied to assess inter- and intraspecific competition with niche and diet overlap and partitioning in West Greenland and the Barents Sea. Seven traits related to resource and habitat utilization were identified in Rossia: no trait was shared by all three species. High boreal R. megaptera and Arctic endemic R. moelleri shared three traits with each other, while both R. megaptera and R. moelleri shared only two unique traits each with widespread boreal-Arctic R. palpebrosa. Thus all traits formed fully uncrossing pattern with each species having unique strategy of resource and habitat utilization. Predicted climate changes in the Arctic would have an impact on competition among Rossia with one potential 'winner' (R. megaptera in the Barents Sea) but no potential 'losers'. [ABSTRACT FROM AUTHOR]

A new free-living marine nematode species of the genus Leptolaimus belonging to the family Laptolaimidae was collected from intertidal sediments of the Shenzhen Mangrove Nature Reserve, Shenzhen, South China, and it is described here as Leptolaimus holovachovi sp. nov. The new species is characterized by body length 734–896 µm in males and 822–941 µm in females; papilliform cephalic sensilla; circular amphideal fovea; males with 7–14 anterior midventral alveoli in the pharyngeal region, 4–5 midventral tubular precloacal supplements and 4–6 alveolar precloacal supplements; spicules slender, slightly arcuate, proximally cephalated and distally pointed. Plate-like gubernaculum without apophyses. The new species differs from other congener species of the genus by the unique feature of having anterior midventral alveoli in the pharyngeal region. [ABSTRACT FROM AUTHOR]

Three benthic Gyrosigma species isolated from sediments of a tropical mangrove in Hainan Island, China, are described using light, scanning and transmission electron microscopy: G. centropunctatum sp. nov., G. dongzhaiense sp. nov. and G. orbitum Thaler et Kaczmarska. Gyrosigma centropunctatum is a tube-dwelling species possessing a unique row of pores on either side of the central area. Gyrosigma dongzhaiense differs from congeners by a combination of small cell size, linear-sigmoid outline, and higher stria density. Gyrosigma orbitum is another tube-dwelling species, which possesses two remarkable oval pits on the external central area. This study expands our knowledge of the marine species diversity and distribution of Gyrosigma in the tropical Western Pacific. We discuss the taxonomic significance of tubes in the species identification of Gyrosigma. [ABSTRACT FROM AUTHOR]

The article discusses the importance of the U.S. leadership in the ocean policy and mentions bipartisan policymakers who serve for coastal nations. It also discusses U.S. heritage of care for oceans and coastlines that has been hard-wired into its government, international ocean issues, and management of marine species.

Two new species of the muricid genus Subpterynotus Olsson and Harbison, 1953 are named from the Neogene fossil beds of southern Florida. These include Subpterynotus gabbi n. sp. from the Early Pleistocene (Gelasian Age) Fort Denaud Member of the Caloosahatchee Formation, and S. feliciae n. sp. from the Late Pliocene (Piacenzian Age) Pinecrest Member of the Tamiami Formation. Both new species had previously been incorrectly assigned to the Langhian Miocene taxon S. textilis (Gabb, 1872) from the Baitoa Formation of the Dominican Republic. Another Floridian species, S. miamiensis Petuch, 1994 from the late Piacenzian Fruitville Member of the Tamiami Formation, is redescribed and compared to S. gabbi, and S. feliciae. [ABSTRACT FROM AUTHOR]

A new species of the marginellid genus Hyalina is described from Brazil. The new species Hyalina cunhai is compared to four other western Atlantic Hyalina species, including H. avenacea Deshayes, 1844, H. moolenbeeki Espinosa & Ortea, 2012, H. pallida Linnaeus, 1758, H. tenuilabra Tomlin, 1917, and five western Atlantic Volvarina species, including V. adrianadiae Cossignani, 2006, V. affinis Reeve, 1865, V. brasiliana Boyer, 2000, V. frazzinii Cossignani, 2006 and V. lactea Kiener, 1841. When compared to these similar species, H. cunhai varies from them with distinct differences in body shape, spire, lip, and body ornamentation. [ABSTRACT FROM AUTHOR]

This paper presents a new Altivasum found off Jurien Bay, Western Australia at 60 m. This new species expands our understanding of the distribution, and in particular extends the northern range of Altivasum, in the South-west Marine Region. Altivasum pauladellaboscae n. sp. is more rhomboidal than A. hedleyi Maxwell and Dekkers, 2019, which is elongated, and has the formation of tubular spines on the shoulder of axial fold on the later whorls of the spire; these spines are not formed in A. pauladellaboscae n sp. Altivasum pauladellaboscae n sp. differs from A. profundum Dekkers and Maxwell, 2018 in having acute shoulder nodules. The South Australian, A. flindersi Verco, 1914 lacks the fibriated subsutural band found in A. pauladellaboscae n. sp. Altivasum clarksoni Maxwell and Dekkers, 2019 is geographically isolated and morphologically distinct, being more elongated and fibriated. This paper brings the number of described Altivasum species to five. [ABSTRACT FROM AUTHOR]

Worldwide, kelp populations are stressed by warming, increased storms and other anthropogenic disturbances. Marine population distributions are projected to retreat poleward with climate change if they cannot adapt to changing conditions, which would potentially lead to a regime shift in subtidal habitats. In Northern Europe, Laminaria hyperborea is a subtidal ecosystem engineer whose distribution has shifted over millennia, leaving predicted areas of high genetic diversity from the last glacial maximum (LGM) near its southern distribution limit in the Iberian Peninsula. In Ireland, L. hyperborea structures communities by supporting diverse faunal assemblages and producing large quantities of organic carbon throughout the year. We investigated the genetic diversity of eight populations, ranging from the southern coast to the north-west of Ireland, using nine microsatellite loci. Diversity was found to be highest in Lough Hyne, a Special Area of Conservation (SAC), near the predicted climate refugium. We found evidence of isolation by distance, with high connectivity between populations that were geographically close, probably driven by short range dispersal of L. hyperborea propagules. Genetic diversity (measured as expected heterozygosity and allelic richness) was highest at Lough Hyne, and decreased northwards, as predicted from past range shifts. Expected heterozygosity was highest at Lough Hyne (0.706) and decreased northward, with the lowest value at Bridges of Ross (0.283). Based on these patterns, further fine-scale investigation into population diversity, dispersal and potential resilience in Irish kelp forests are necessary as warming and non-native species are observed more and more frequently. [ABSTRACT FROM AUTHOR]

Microplastic pollution is ubiquitous in the marine environment and is ingested by numerous marine species. Sharks are an understudied group regarding their susceptibility to microplastic ingestion. Here, we provide evidence of ingestion of microplastic and other anthropogenic fibres in four demersal sharks species found in the waters of the United Kingdom and investigate whether body burdens of contamination vary according to species, sex or size. Sharks were collected from the North-East Atlantic. Stomachs and digestive tracts of 46 sharks of 4 species were examined and 67% of samples contained at least one contaminant particle. Although we acknowledge modest sample size, estimated particle burden increased with body size but did not vary systematically with sex or species. A total of 379 particles were identified, leading to median estimates ranging from 2 to 7.5 ingested contaminants per animal for the 4 species. The majority were fibrous in nature (95%) and blue (88%) or black (9%) in colour. A subsample of contaminants (N = 62) were subject to FT-IR spectroscopy and polymers identified as: synthetic cellulose (33.3%), polypropylene (25%), polyacrylamides (10%) and polyester (8.3%). The level of risk posed to shark species by this level of contamination is unknown. Nevertheless, this study presents the first empirical evidence and an important baseline for ingestion of microplastics and other anthropogenic fibres in native UK shark species and highlights the pervasive nature of these pollutants. [ABSTRACT FROM AUTHOR]

The population explosion of jellyfish Aurelia coerulea occurred in Jiaozhou Bay, China in 2009. The potential predation impact of A. coerulea on zooplankton was investigated. Population clearance potential and residence time (t1/2) for copepods were calculated from laboratory clearance rates and measurements of jellyfish size and abundance from May to August 2009 in Jiaozhou Bay. Clearance rates varied widely with prey organisms, but they were not significantly different among various prey concentrations. Medusae captured rotifers, fish larvae and hydromedusae more efficiently than fish eggs, copepods and chaetognaths. Ephyrae captured rotifers and hydromedusae more efficiently than fish larvae and copepods. Clearance rate linearly increased with the cross sectional area of A. coerulea (size from 0.3 to 7.1 cm). Water temperature also had a marked effect on clearance rate and this was related to the increased beat frequency as water temperature increased. In early May 2009, A. coerulea potentially cleared the volume of water in the Bay less than 0.001 times a day, but this value was estimated to be more than 0.3 times a day in July. The t1/2 for copepods was less than 6 d in June and July. Abundances of copepods, hydromedusae and chaetognaths were extremely low in 2009 compared to 2008 and 2010 (jellyfish non-bloom years). Large predation pressure by the A. coerulea population occurred to control zooplankton communities in Jiaozhou Bay. A. coerulea, when present at a high population level, can be a keystone species in Jiaozhou Bay and control the trophic structure here. [ABSTRACT FROM AUTHOR]

In fish, the fat content contributes to promoting the nutritional and organoleptic characteristics of the flesh, which is crucial for consumer acceptance. Methods to predict the fat in fish are important in nutritional and physiological research, where body content is traditionally determined by dissection followed by chemical analysis. However, X-ray micro-computed tomography (micro-CT) provides three-dimensional information in a non-destructive way. This work aims to characterize radiologically the fat, in situ, in a widely cultivated marine species, gilthead seabream (Sparus aurata). To validate the method changes in fat content in a control group (fed) and another group (unfed for 60 days) were assessed. Fish images were acquired on an Albira SPECT/PET/CT preclinical-scanner. Image analysis and measurements were performed using the Carestream Molecular Imaging Albira CT system in conjunction with Pmod and Amide packages. By micro-CT analysis the density values were determined for the whole fish body (− 1,000 to + 2,500 HU, Hounsfield units), and density ranges for the fat in S. aurata were established from − 115 to + 50 HU. As expected, significant differences were found between fed and starved groups at 60 days. The present study confirms the usefulness of high-resolution morphological analysis for evaluating the presence and distribution of fat in this important fish species. [ABSTRACT FROM AUTHOR]

The ichthyo-fauna in the Ba Che and Tien Yen rivers, northern Vietnam is highly diverse, with a total of 245 species determined. However, data on the distribution of fish species are not sufficiently provided for the whole area. This study was conducted from 2008 to 2011 at 27 stations from the Ba Che and Tien Yen river basins to determine the distribution of fish species according to different sections of the rivers, water bodies, seasons, and salinity levels. The results show that fish species are distributed mainly in the river (with 210 species), concentrated in the downstream area (with 213 species). Fishes are mainly collected in the dry season when the salinity level of river is high, due to seawater intrusion which also brings in 160 species of marine fish. This shows that fish distribution in the research areas is mainly dominated by the presence of marine species. While for freshwater fish, it is clearly affected by the mountainous features. Apart from the common characteristics sharing between the two river basins, but the number of both freshwater and marine fish species in the Tien Yen river are larger than those of Ba Che river, which is related to fresh water surface, river morphology, the width and location of the estuary to the sea. The downstream area is home to the fish species recorded in the Red Data Book of Vietnam and the complementary species for Vietnam, while the middle and upstream of the rivers may offer a high potential of biodiversity, with many possibly new species for science. These are important data for the conservation and sustainable development of fish resources in the Ba Che and Tien Yen river basins [ABSTRACT FROM AUTHOR]

Although adult cane toads (Rhinella marina) are generally active only at night, a recent study reported that individuals of this species switched to diurnal activity in response to encountering a novel habitat type (deeply shaded gorges) in the course of their Australian invasion. Our sampling over a broader geographic scale challenges the idea that this behaviour is novel; we documented diurnal behaviour both in the species' native range and in several sites within the invaded range, in multiple habitat types. Diurnal activity was most common in the tropics and in areas where toads attain high population densities and are in poor body condition, suggesting that the expansion of activity times may be induced by intraspecific competition for food. [ABSTRACT FROM AUTHOR]

The Toarcian Oceanic Anoxic Event (TOAE, Early Jurassic, ~182 Ma ago) was characterised by severe environmental perturbations which led to habitat degradation and extinction of marine species. Warming-induced anoxia is usually identified as main driver, but because marine life was also affected in oxygenated environments the role of raised temperature and its effects on marine life need to be addressed. Body size is a fundamental characteristic of organisms and is expected to decrease as a response to heat stress. We present quantitative size data of bivalves and brachiopods across the TOAE from oxygenated habitats in the Iberian Basin, integrated with geochemical proxy data (δ13C and δ18O), to investigate the relationship between changes in temperature and body size. We find a strong negative correlation between the mean shell size of bivalve communities and isotope-derived temperature estimates, suggesting heat stress as a main cause of body size reduction. While within-species size changes were minor, we identify changes in the abundance of differently sized species as the dominant mechanism of reduced community shell size during the TOAE. Brachiopods experienced a wholesale turnover across the early warming phase and were replaced by a virtually monotypic assemblage of a smaller-sized, opportunistic species. [ABSTRACT FROM AUTHOR]

The classical theory of island biogeography, which predicts species richness using island area and isolation, has been expanded to include contributions from marine subsidies, i.e. subsidized island biogeography (SIB) theory. We tested the effects of marine subsidies on species diversity and population density on productive temperate islands, evaluating SIB predictions previously untested at comparable scales and subsidy levels. We found that the diversity of terrestrial breeding bird communities on 91 small islands (approx. 0.0001–3 km2) along the Central Coast of British Columbia, Canada were correlated most strongly with island area, but also with marine subsidies. Species richness increased and population density decreased with island area, but isolation had no measurable influence. Species richness was negatively correlated with marine subsidy, measured as forest-edge soil δ15N. Density, however, was higher on islands with higher marine subsidy, and a negative interaction between area and subsidy indicates that this effect is stronger on smaller islands, offering some support for SIB. Our study emphasizes how subsidies from the sea can shape diversity patterns on islands and can even exceed the importance of isolation in determining species richness and densities of terrestrial biota. [ABSTRACT FROM AUTHOR]