Progress in Oceanography最新文献

{"title":"Episodic deep vertical mixing in the Rhodes gyre (Mediterranean Sea) triggers an exceptional mesozooplankton outburst","authors":"Ioanna Siokou ,&nbsp;Nikolaos Simantiris ,&nbsp;Epaminondas D. Christou ,&nbsp;Alexander Theocharis","doi":"10.1016/j.pocean.2025.103496","DOIUrl":"10.1016/j.pocean.2025.103496","url":null,"abstract":"<div><div>The Northwest Levantine Basin of the Eastern Mediterranean Sea has been historically considered as the source region of the Levantine Intermediate Water of the Mediterranean, which is formed in the permanent Rhodes cyclonic gyre. In late winter-early spring 1992, an unusual deep mixing of the water column down to 2000 dbar was observed. This event, caused by synergy of extreme meteorological winter conditions and hydrodynamical regime, led for first time to deep water formation; the new Levantine deep water mass replaced and/or mixed locally with the deep water mass of Adriatic origin, which dominated since the beginning of the 20th century. The hydrological characteristics of the newly formed water were different from the old ones, which historically occupied the deep and bottom layers of the entire Eastern Mediterranean. Since then, similar extreme event has not been reported. Mesozooplankton samples were collected in the 0–300 m layer of the Rhodes gyre, the Cretan Sea and the Cretan Passage. Zooplankton abundance was found three to fivefold higher in the 0–50 m layer of the Rhodes gyre than in that of the adjacent areas. This increase should be related to the water deep mixing and the resulted uplifting of nutrients and phytoplankton increment. In the core of the gyre and down to 300 m, the community was characterized by the abundance of <em>Subeucalanus monachus</em> adults, late copepodids and nauplii (almost 50 % of copepods in the 0–50 m layer). The formation of the new Levantine deep water in combination with the Eastern Mediterranean Transient event that was in progress, revealed a new hydrological regime in the NW Levantine Sea compared to the traditional one. The observed very deep convection supported an exceptional mesozooplankton outburst in a cyclonic gyre surrounded by the very oligotrophic Eastern Mediterranean waters.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103496"},"PeriodicalIF":3.8,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating isoscapes and amino acid δ15N analyses to reveal migration patterns and habitat use of molids in the western Pacific Ocean","authors":"Ching-Tsun Chang ,&nbsp;Daniel J. Madigan ,&nbsp;Aaron B. Carlisle ,&nbsp;Natalie Wallsgrove ,&nbsp;Itsumi Nakamura ,&nbsp;Marianne Nyegaard ,&nbsp;Valerie Allain ,&nbsp;Jeffrey C. Drazen ,&nbsp;Wei-Chuan Chiang ,&nbsp;Brian N. Popp","doi":"10.1016/j.pocean.2025.103492","DOIUrl":"10.1016/j.pocean.2025.103492","url":null,"abstract":"<div><div>Understanding the movement ecology and resource use of pelagic fishes is essential for their conservation and management. Molids, as predators of gelatinous zooplankton, play important ecological roles in the gelatinous food webs and undertake long-distance migrations across the Pacific Ocean. This study used a novel combination of isotope-based approaches, including isoscapes, compound-specific isotope analysis of amino acids, and Bayesian mixing models, to investigate the migration patterns and habitat uses of molids (<em>Mola mola</em> and <em>M. alexandrini</em>) at a population level in the western Pacific Ocean. Results from isoscapes revealed that most molids in Japan, Taiwan, and New Caledonia might be local residents, with measured δ¹⁵N values aligning with predicted isoscape values. However, some larger individuals in Japan and Taiwan showed δ¹⁵N values higher than predicted, suggesting recent migrations from isotopically distinct regions. In New Zealand, the measured δ¹⁵N values of molids did not overlap with predicted values, indicating non-residency. Source amino acid δ¹⁵N values and Bayesian mixing models suggest that local residents in Japan and Taiwan primarily consumed local prey, whereas recent migrants with higher δ¹⁵N values may originate from the warm pool region, potentially linked to spawning behavior. Molids in New Caledonia and New Zealand likely migrate from regions with isotopic values distinct from the local food web base. The cross-regional movements of molids highlight the importance of understanding connectivity within the western Pacific Ocean. Identifying migratory corridors and key habitats, such as spawning and feeding grounds, is essential for developing regional and international conservation strategies that ensure the long-term sustainability of molid populations.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103492"},"PeriodicalIF":3.8,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143931982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upper-layer circulation at the mouth of Amundsen Gulf, Arctic Ocean","authors":"Peigen Lin ,&nbsp;Robert S. Pickart ,&nbsp;Maria Pisareva ,&nbsp;Bill Williams","doi":"10.1016/j.pocean.2025.103491","DOIUrl":"10.1016/j.pocean.2025.103491","url":null,"abstract":"<div><div>Amundsen Gulf, located between the Canadian north slope and Banks Island, is the western-most entrance to the Canadian Arctic Archipelago, providing a bridge between the western Arctic Ocean and the North Atlantic. Using timeseries from 13 moorings in the vicinity of the mouth of Amundsen Gulf deployed from 2003 to 2004, we investigate the mean state and dominant variability of the circulation in the upper 50 m layer which consists of boundary currents on both sides of the gulf and anticyclonic recirculation in the interior. We find that the flow on the western side of the gulf switches directions in response to the wind: inflow under northwesterly winds and outflow under southeasterly winds. Such a relationship persists throughout the year, except during periods of fast ice coverage. By contrast, the current on the eastern side of Amundsen Gulf consistently flows into the gulf for most of the year and is only weakly correlated with the western boundary current or local winds. Instead, the flow aligns more with the circulation along the eastern side of Banks Island which is linked to the southeastern extension and movement of the Beaufort Gyre, and, in turn, the basin-scale wind stress curl. Three distinct water masses were observed at the mouth of the gulf during the year-long period: fresh water in fall that originates in the basin and penetrates into the gulf; cold/salty water in winter that is intermittently advected into the gulf from the eastern boundary current; and warm water in summer that appears in open ocean regions where atmospheric heating occurs, independent of the detailed circulation structure.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103491"},"PeriodicalIF":3.8,"publicationDate":"2025-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Massive occurrence of a new soft-walled monothalamous foraminifer, Bathyallogromia brandtae n.sp., in the hadal Aleutian trench","authors":"Jan Pawlowski ,&nbsp;Andrew J. Gooday ,&nbsp;Maria Holzmann","doi":"10.1016/j.pocean.2025.103493","DOIUrl":"10.1016/j.pocean.2025.103493","url":null,"abstract":"<div><div>Large numbers of spherical, organic-walled, monothalamous foraminifera were observed and isolated from the fine-sized sediment fraction collected at hadal depths in the Aleutian trench. The foraminifer was one of the few living species found among diatom frustules that make up most of this sediment fraction. Morphologically, the species resembles the genus <em>Bathyallogromia</em> described from the Weddell Sea and subsequently found in the abyssal Arctic Ocean, and other high latitude areas but never in such massive abundance. Molecular phylogenetic analyses based on partial 18S rRNA gene sequences confirmed its generic identification as a new species within the <em>Bathyallogromia</em> clade that is described here as <em>Bathyallogromia brandtae</em> sp.nov. Our study offers new evidence that deep-sea monothalamous foraminifera can proliferate in extreme hadal settings and have biogeographic distributions that are more restricted than is commonly assumed.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103493"},"PeriodicalIF":3.8,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Basin-wide morphology and metabarcoding-based comparison of ichthyoplankton diversity and community structure in the Gulf of Mexico","authors":"Miguel A. Martínez-Mercado ,&nbsp;Jesus C. Compaire ,&nbsp;Frank J. Hernández ,&nbsp;Glenn Zapfe ,&nbsp;Sylvia P.A. Jiménez-Rosenberg ,&nbsp;Anaid Saavedra-Flores ,&nbsp;Clara E. Galindo-Sánchez ,&nbsp;Leticia Barbero ,&nbsp;Sharon Z. Herzka","doi":"10.1016/j.pocean.2025.103482","DOIUrl":"10.1016/j.pocean.2025.103482","url":null,"abstract":"<div><div>Comprehensive surveys of marine fish egg and larval assemblages provide insight into spawning distribution, dispersal, transport processes, connectivity, and recruitment. We report on a rare basin-wide synoptic survey of fish eggs and larvae sampled throughout the Gulf of Mexico (GoM), including the Loop Current (LC) and Bahamas Channel in the Atlantic. Based on paired sample collections, we identified fish larvae through morphology-based identification at the family level and with cytochrome oxidase I metabarcoding to genera or species; eggs were identified by metabarcoding. Sampling within one-month during summer 2017 included on-shelf (&lt;200 m depth) and off-shelf stations (depths &gt;1000 m). We found general agreement between identification approaches at the family level, but the higher taxonomic resolution achieved with metabarcoding and the inclusion of ecological information such as adult habitat indicated three predominant assemblages: oceanic, shelf, and LC-associated. In larval samples, 72 and 77 families were identified based on morphology and metabarcoding, respectively and 62 families (70 %) were identified with both methods. Thirty-nine families were identified in fish egg samples, likely due to their shorter stage duration. The greater taxonomic resolution of metabarcoding yielded 265 and 75 species in larvae and egg samples, respectively. While family-level diversity indices did not differ between on and off-shelf assemblages, species-level analysis indicated significantly higher egg and larval diversity at on-shelf stations. Hence, family-level analyses may be too coarse to elucidate patterns in alpha diversity. Family-level cluster analysis indicated on– and off-shelf stations grouped separately, except for an off-shelf station off the Mississippi River that reflected local offshore transport of neritic taxa. Metabarcoding detected an additional cluster within the LC’s path of travel that included Caribbean reef taxa. All off-shelf stations included larvae of neritic families, reflecting offshore transport throughout the GoM. In contrast, only some on-shelf stations included oceanic families, indicating less prevalent oceanic-to-shelf transport. Amplicon sequence variants, roughly indicative of abundance, showed a positive association with mean water column temperature and dissolved oxygen, known to influence spawning and larval growth and development, as well as surface chlorophyll, a proxy for larval food availability. Off-shelf stations were positively correlated with indicators of water masses and mesoscale eddies. Similar results were found for the egg stage, but the correlation with chlorophyll <em>a</em> was insignificant, consistent with endogenous feeding during the embryonic stage. Our synoptic view of the GoM’s early life stages of fishes can serve as a reference for examining the impacts of climate change and other anthropogenic disturbances.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103482"},"PeriodicalIF":3.8,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variability and forcings of high turbidity events in the northern Adriatic sea from analysis of in-situ long-term data: A methodological approach","authors":"Francesco Riminucci ,&nbsp;Davide Bonaldo ,&nbsp;Lucilla Capotondi ,&nbsp;Mariangela Ravaioli ,&nbsp;Caterina Bergami","doi":"10.1016/j.pocean.2025.103483","DOIUrl":"10.1016/j.pocean.2025.103483","url":null,"abstract":"<div><div>Long-term data series (2012–2021) of physical and oceanographic parameters at the LTER-Italy research site “Delta del Po and Costa Romagnola’’, encompassing the Po river delta and the surrounding coastal areas, were analyzed to investigate the variability of surface turbidity in the North-Western Adriatic shelf. This shallow coastal environment is characterized by high river runoff, strong variability in wind regimes (direction and speed) and sea state (wave height). Both meteorological and oceanographic factors drive the local pattern of surface turbidity. This study focuses on an in-situ data analysis to recognize the main forcing responsible for high surface turbidity events (HTEs) along the coastal area. The dataset analyzed combines surface optical turbidity and salinity data, along with meteorological, hydrographic, and wave data from fixed point observing systems. While the main and most intense turbidity events (NTU &gt; 10) in the Po Delta area are primarily caused by suspended sediments from river floods and wind-driven resuspension events, the high correlation between turbidity and wave height indicates that waves are primary driving factors along the Emilia-Romagna coast southward. The results from this study provide a methodological approach based on thresholds and proxies of physical parameters for quantifying variations of HTEs and identifying their main forcing in coastal areas.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103483"},"PeriodicalIF":3.8,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143885926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Connection of central South China Sea current variability with tropical Rossby waves in the western North Pacific","authors":"Mac Euan D. Malugao ,&nbsp;Sen Jan ,&nbsp;Ming-Huei Chang ,&nbsp;Tung-Yuan Ho ,&nbsp;Yiing Jang Yang","doi":"10.1016/j.pocean.2025.103481","DOIUrl":"10.1016/j.pocean.2025.103481","url":null,"abstract":"<div><div>This study investigates the connection between the current velocity variations in the central South China Sea (SCS) and westward-propagating tropical Rossby waves in the western North Pacific, using satellite altimeter observations and coastal tide-gauge data supplemented by numerical modeling. This work is focused on the dynamic link between the intraseasonal velocity oscillations observed in the central-eastern SCS in summer 2017 and the Rossby waves that impinge on the east coast of the Philippine Archipelago. Low-pass-filtered satellite sea level anomaly (SLA) data and coastal sea level records suggest that Rossby waves can propagate into the Celebes Sea and Sulu Sea, eventually reaching the central SCS. A three-dimensional, primitive equation model shows that Rossby wave-associated SLA signals transmit through the Philippine Archipelago to the central SCS via the Celebes Sea-Sibutu Passage-Sulu Sea-Mindoro Strait route, with modeled SLA propagation timings that are consistent with the observations. As the Rossby wave reaches the eastern Philippines, approximately one-third of the incident wave energy from a meridional section east of the Philippines (132°E, between 2°N and 15°N) is transmitted into the Celebes Sea and Luzon Strait, whereas approximately two-thirds of the energy is dissipated, transformed, or reflected along the Philippine coast. Approximately 15 % of the energy entering the Celebes Sea passes through the Sibutu Passage into the Sulu Sea, and ∼10 % exits the Mindoro Strait into the central SCS. These suggest that 2−5 % of the incident energy from the western North Pacific transmitted into the central SCS and influences sea level and velocity variations there.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103481"},"PeriodicalIF":3.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143885925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linking physical processes to biological responses: Interdisciplinary observational insights into the enhanced biological productivity of the Cape Verde Archipelago","authors":"Florian Schütte ,&nbsp;Anna Christina Hans ,&nbsp;Marco Schulz ,&nbsp;Rebecca Hummels ,&nbsp;Olivier Assokpa ,&nbsp;Peter Brandt ,&nbsp;Rainer Kiko ,&nbsp;Arne Körtzinger ,&nbsp;Björn Fiedler ,&nbsp;Tim Fischer ,&nbsp;Elizandro Rodrigues ,&nbsp;Henk-Jan Hoving ,&nbsp;Helena Hauss","doi":"10.1016/j.pocean.2025.103479","DOIUrl":"10.1016/j.pocean.2025.103479","url":null,"abstract":"<div><div>The Cape Verde Archipelago (CVA) is a hotspot of biological productivity in the oligotrophic central North Atlantic, supporting a highly diverse ecosystem. Twenty years of interdisciplinary observational data are used to investigate the primary physical processes driving this productivity and their impacts on the composition of biological life across the food web of the CVA. Three dominant physical processes are identified: <strong><em>I.</em></strong> <em>Atmospheric forced island wakes:</em> Wind interactions with the topography of Santo Antão and Fogo generate local wind shear, creating surface-intensified, productive eddy fields that extend several island diameters downstream. <strong><em>II.</em></strong> <em>Interaction of remotely generated mesoscale eddies with the CVA:</em> Nitrate-rich eddies generated off the coast of West Africa interact with the CVA by colliding with the eastern islands, or by passing near shallow bathymetry. This interaction enhances submesoscale activity, likely driven by unbalanced mesoscale flow, leading to hotspots of vertical advection and mixing. Our observations indicate, in addition, interactions between passing eddies and island-induced processes, such as an elevated internal wave field and wind curl in lee of the islands. This results in up to a tenfold increase in mixing within near-island eddies. <strong><em>III.</em></strong> <em>Interactions of tidal flows and internal waves with the CVA:</em> Internal wave breaking at specific hotspots, such as south of Santo Antão, leads to elevated vertical mixing rates, up to 1000 times higher than at reference points. The mean internal wave field in the CVA is over twice as energetic as in the open ocean, and even stronger at distinct hotspots. These three physical processes, although different in nature, all enhance upward nitrate flux, thereby promoting significantly higher chlorophyll concentrations. This, in turn, forms the foundation of the local pelagic food web, including mesozooplankton and micronekton, such as mesopelagic fishes, whose abundance increase three- to tenfold at these local hotspots. The composition of the biological communities is highly diverse and varies across different regions and physical processes. Annual landings of mackerel and tuna on the CVA, as well as the abundance of humpback whales, are positively correlated with annual mean chlorophyll concentrations. Overall, our study reveals a strong correlation between nitrate supply to the euphotic zone, driven by various physical processes, and species abundance throughout the food web, extending to large predators. These findings underscore the crucial role of local physical processes in shaping the structure of marine communities from lower to higher trophic levels, explaining biological diversity in the marine environment of the CVA and beyond.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103479"},"PeriodicalIF":3.8,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping internal lee wave generation and dissipation in the deep South China sea","authors":"Zhenhua Xu ,&nbsp;Ji Li ,&nbsp;Peiwen Zhang ,&nbsp;Jia You ,&nbsp;Jianping Gan","doi":"10.1016/j.pocean.2025.103474","DOIUrl":"10.1016/j.pocean.2025.103474","url":null,"abstract":"<div><div>Abyssal mixing induced by internal wave breaking has been proposed as an essential process that maintains and modulates the deep cyclonic circulation and meridional overturning circulation in the South China Sea (SCS). Previous studies have primarily focused on internal tides, leaving limited exploration on internal lee waves and their roles in mixing the SCS. This study represents the first basin-scale estimation of the lee-wave energy flux from the geostrophic flow and exploration of lee-wave-induced mixing in the SCS. Utilizing an improved spectra method with the synthetic full-scaled bathymetry, lee wave generation is estimated employing Bell theory with the outputs from the China Sea Multi-Scale Ocean Modeling System. The Luzon Strait (LS) features the strongest lee wave generation, reaching up to 19.7 GW. In the SCS interior, the total energy flux is estimated at 1.3 GW, with 70% occurring in the deep basin. In the basin area, energy flux from the mean flow surpasses that from eddy flow, whereas in the marginal area, the dominant energy flux is from eddy flow. This study reveals seasonal variation in lee wave generation, closely related to the seasonality of the deep-water overflow from the LS. The mixing driven by lee waves is found comparable with that driven by internal tides in the deep SCS basin. This study emphasizes the potentially significant lee wave energy and induced mixing in the deep SCS basin, which should be well-mapped and parameterized in ocean models for a better characterization of multiscale dynamics and energetics in the SCS.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"235 ","pages":"Article 103474"},"PeriodicalIF":3.8,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143879489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinorhyncha community in the Aleutian Trench (North Pacific Ocean) with the description of a new Cristaphyes species (Allomalorhagida, Pycnophyidae)","authors":"Nuria Sánchez ,&nbsp;Frederic Bonk ,&nbsp;Alberto González-Casarrubios","doi":"10.1016/j.pocean.2025.103475","DOIUrl":"10.1016/j.pocean.2025.103475","url":null,"abstract":"<div><div>Several species of trench-dwelling meiofaunal animals, including Kinorhyncha, have been described in recent years; however, our knowledge on kinorhynchs inhabiting abyssal and even hadal depths is still extremely scarce. In the present study, we explore the Kinorhyncha community of the Aleutian Trench, North Pacific Ocean, an under-sampled region in terms of meiofauna. As a result, a new species of <em>Cristaphyes</em> inhabiting abyssal and hadal depths of the trench is described. <em>Cristaphyes unangax</em> sp. nov. is characterized by the presence of middorsal processes on segments 1 – 10, with the last one extending well-beyond the posterior margin of the trunk. <em>Cristaphyes unangax</em> sp. nov. thus becomes the fourth hadal species described within the phylum Kinorhyncha. In terms of biodiversity, abundance of adult kinorhynchs remains relatively low along the trench’s depth gradient (c.a. 3.500 – 7.200 m), except at two sites: one at the axis and another at the slope. The higher abundance at the axis aligns with patterns in other trenches, where organic matter accumulation enhances microbial activity, supporting meiofaunal communities. The elevated specimens at the slope station, located at abyssal depth, may result from Aleutian upwelling currents or trench terraces that facilitate food deposition. The Kinorhyncha community in the Aleutian Trench is dominated by <em>Echinoderes ultraabyssalis</em> and includes another nine species, many shared with the North Pacific and Arctic. These findings suggest that meiofauna in the North Pacific can disperse across bathymetric barriers, potentially linking the Aleutian and Kuril-Kamchatka trenches. Additionally, the Aleutian Trench may serve as a migration corridor for meiofauna between the North Pacific and Arctic, aided by strong bottom currents.</div><div><strong>Zoobank</strong>: urn:lsid:zoobank.org:pub:56D1BA0B-3D9F-4547-84BC-C9BAFCA1D220</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":"236 ","pages":"Article 103475"},"PeriodicalIF":3.8,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144084481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}