Five new species of Terebellides (Annelida, Polychaeta, Trichobranchidae) from Papua New Guinea (Bismarck and Solomon seas)
Five new species of Terebellides are described from coastal and deep waters of Papua New Guinea, using both morphology and molecular tools (for four species). Terebellides elenae n. sp. is characterized by the absence of both a glandular lateral region on TC3 and papillae on margins of the branchial lamellae and by the presence of partially fused branchial lobes with conspicuous fifth lobe and dorsal rounded projections until TC6. Terebellides fauchaldi n. sp. has a very large glandular lateral region on the third thoracic chaetiger (TC3), a fifth branchial lobe and partially fused branchial lobes, and conspicuous dorsal rounded projections on TC2–6. Terebellides madeep n. sp. is characterized by a thin glandular region on TC3 and by four free branchial lobes. Terebellides oculata n. sp. is one of the only two species in the world to have eyespots. Finally, T. papillosa n. sp. has geniculate chaetae on TC6 and TC7 and bears a large number of papillae. A majority-rule consensus tree using the 16S gene and an identification key for all Terebellides species described from the Central Indo-Pacific region are provided.
(Frontiers in Ecology and Evolution. vol. 12, n° 2296-701X, pp. 1349362, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, USP, UMS POREA, INSU - CNRS, CNRS, INRAE
A critical review of pollution active biomonitoring using sentinel fish: Challenges and opportunities
Water pollution is a significant threat to aquatic ecosystems. Various methods of monitoring, such as in situ approaches, are currently available to assess its impact. In this paper we examine the use of fish in active biomonitoring to study contamination and toxicity of surface waters. We analysed 148 previous studies conducted between 2005 and 2022, including both marine and freshwater environments, focusing on the characteristics of the organisms used as well as the principal goals of these studies. The main conclusions we drew are that a wide range of protocols and organisms have been used but there is no standardised method for assessing the quality of aquatic ecosystems on a more global scale. Additionally, the most commonly used developmental stages have been juveniles and adults. At these stages, the most frequently used species were the fathead minnow (Pimephales promelas) and two salmonids: rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta). Few studies used earlier stages of development (embryos or larvae), mostly due to the difficulty of obtaining fish embryos and caging them in the field. Finally, we identified research gaps in active biomonitoring for water quality assessment which could indicate useful directions for future research and development.
(Environmental Pollution. vol. 360, n° 0269-7491, pp. 124661, 10/04/2026)
UR EABX, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, RiverLy, INRAE
Reactivity and fluxes of antimony in a macrotidal estuarine salinity gradient: Insights from single and triple quadrupole ICP-MS performances
Trace element analyses in brackish waters are challenging for many elements at ppb/ppt levels and analytical methods. In this work, we compare two methods using inductively coupled plasma mass spectrometry (ICP-MS) for quantifying antimony (Sb). Results of a previous study along the salinity gradient in a macrotidal estuary (i.e., the Gironde Estuary, France) using isotopic dilution via single quadrupole ICP-MS are compared to reanalyzed aliquots of the same samples. Direct analyses of estuarine water samples via standard additions (N = 52) were performed with a QQQ-ICP-MS (new generation, iCAP TQ Thermo®) to determine dissolved (< 0.2 µm filtered and UV-irradiated replicates) Sb concentrations during two contrasting hydrological conditions (low vs high freshwater discharges). Despite following good analytical practices on both studies, the use of the new analytical device provides more robust results and highlighted a characteristic 121Sb isotopic interference in estuarine samples at S > 20, efficiently eliminated by the QQQ-ICP-MS performance. This means that Sb reactivity shows an additive, non-conservative behavior in the Gironde Estuary, with a more defined bell-shaped profile in low discharge compared to high discharge conditions. This approach allows to quantify for the first time in the literature Sb dissolved net fluxes from the Gironde Estuary to the Atlantic coast and provides an updated value for the seawater endmember. This study opens future applications of QQQ-ICP-MS for quantifying on a more routine basis dissolved trace elements in brackish waters, providing guidelines and good practices for field studies regarding Sb determination in estuarine systems.
(Marine Chemistry. vol. 267, n° 0304-4203, pp. 104465, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, KIT
Blood kinetics of lipophilic and proteinophilic pollutants during two types of long-term fast in king penguins
In vertebrates, fasting is an intricate physiological process associated with strong metabolic changes, yet its effect on pollutant residues variation is poorly understood. Here, we quantified long-term changes in plasma concentrations of 20 organochlorine and 16 perfluoroalkyl pollutants in king penguins Aptenodytes patagonicus during the breeding and molting fasts, which are marked by low and high levels of protein catabolism, respectively, and by strong lipid use. The profile of measured pollutants in plasma was dominated by perfluorooctanesulfonic acid (PFOS, initial relative contribution of 60%). Initial total pollutant concentrations were similar in molting (3.3-5.7 ng g-1 ww) and breeding penguins (range 4.2-7.3 ng g-1 wet weight, ww). Long-term fasting (25 days) for molting and breeding led, respectively, to a 1.8- and 2.2-fold increase in total plasma pollutant concentrations, though the rate and direction of change was compound-specific. Hexachlorbenzene (HCB) and PFOS concentrations increased in plasma (net mobilization) during both types of fast, likely due to lipid use. Plasma perfluoroundecanoate (PFUnDA) and perfluorotridecanoate (PFTrDA) concentrations increased in breeders (net mobilization), but decreased in molting individuals (net excretion), suggesting a significant incorporation of these pollutants into feathers. This study is a key contribution to our understanding of pollutant variation in blood during long-term fasting in wildlife.
(Environmental Science and Technology. vol. 58, n° 0013-936X, pp. 6138--6148, 10/04/2026)
LIENSs, INSU - CNRS, ULR, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMR MARBEC, IRD, IFREMER, CNRS, UM, CEBC, ULR, CNRS, INRAE
Understanding sediment and carbon accumulation in macrotidal minerogenic saltmarshes for climate resilience
Coastal saltmarshes play an essential role in providing services such as coastal protection, support for biodiversity, and sediment and carbon storage. Despite their importance, understanding the factors controlling sediment and carbon accumulation in these minerogenic saltmarshes remains challenging due to their diversity and site-specific characteristics. Understanding the respective role of these drivers is essential for effective coastal management, particularly for mitigating the impacts of climate change. This study evaluates the control of forcing factors on the lateral and vertical morphological evolution and carbon burial rates of three minerogenic saltmarshes located on the French Atlantic coast (Pertuis Charentais region). By focusing on these sites, the study isolates specific factors such as wind and wave exposure, inundation frequency, and sediment availability, while minimizing confounding influences like climate and tidal range. Results reveal significant lateral expansion of saltmarsh boundaries towards the sea across all sites, with the highest rates of progradation observed in the protected areas influenced by geomorphological features such as sand spits and sheltered bay heads. Sediment and mass accumulation rates (SAR; MAR), derived from 210Pb and 137Cs profiles of sediment cores (n = 14), range from 0.48 to 2.22 cm yr-1, among the highest reported globally, with notable variability within and between sites. Inundation frequency and accommodation space explain SAR variability within sites, while sediment availability predominantly determines spatial differences in vertical accumulation rates between sites. Organic carbon burial rates range from 75 to 345 gC m -2 yr-1, and show a strong correlation with SAR (r = 0.9, p<0.001, n = 13) but no dependence on carbon content or density (r = 0.2, p<0.05, n = 13). This highlights the role of sediment input in the accumulation and sequestration of carbon by minerogenic saltmarshes. Furthermore, isotopic analysis indicates a marine source dominance in organic carbon sediment. This research provides insights into how different environmental conditions affect saltmarsh morphological evolution and carbon sequestration rates, informing targeted coastal management strategies focused on enhancing ecosystem resilience and climate resilience.
(Geomorphology. vol. 467, n° 0169-555X, pp. 109465, 10/04/2026)
LIENSs, INSU - CNRS, ULR, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
A new species of Malacoceros (Annelida, Polychaeta, Canalipalpata, Spionidae) from urban waters in Gabon
A new species of Malacoceros is described from estuarine equatorial waters in Libreville (Gabon, West Africa). During a recent environmental study aimed to assess the urban impact on an estuarine ecosystem near Libreville, the collection of sediment samples from the area was undertaken. The local invertebrate macrofauna had not been previously well studied, and to document the biodiversity, specimens were examined in more detail. A new species of Malacoceros was discovered, occurring in mangrove areas. The new species is described and illustrated in detail, and information on three molecular markers was retrieved and partially used for species delimitation analysis. The new species resembles Malacoceros indicus (Fauvel 1928) described from India but is easily distinguished by a very conspicuous morphological character, the presence of 7–11 large tubercles along the anterior margin of the prostomium. The presence of such conspicuous tubercles has never been observed before in Malacoceros. Maximum likelihood trees for species of Malacoceros and the close genera of Rhynchospio, for which we have data, are also provided. The suitability of characters used for species delimitation in Malacoceros is discussed.
(African Zoology, n° 1562-7020, pp. 1--16, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMR MARBEC, IRD, IFREMER, CNRS, UM
Revealing the profound influence of diapause on gene expression: Insights from the annual transcriptome of the copepod Calanus finmarchicus
Abstract Annual rhythms are observed in living organisms with numerous ecological implications. In the zooplanktonic copepod Calanus finmarchicus , such rhythms are crucial regarding its phenology, body lipid accumulation, and global carbon storage. Climate change drives annual biological rhythms out of phase with the prevailing environmental conditions with yet unknown but potentially catastrophic consequences. However, the molecular dynamics underlying phenology are still poorly described. In a rhythmic analysis of C. finmarchicus annual gene expression, results reveal that more than 90% of the transcriptome shows significant annual rhythms, with abrupt and dramatic upheaval between the active and diapause life cycle states. This work explores the implication of the circadian clock in the annual timing, which may control epigenetic mechanisms to profoundly modulate gene expression in response to calendar time. Results also suggest an increased light sensitivity during diapause that would ensure the photoperiodic entrainment of the endogenous annual clock.
(Molecular Ecology. vol. 33, n° 0962-1083, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, SAMS, MIAT INRAE, INRAE, JMU, HIFMB, OFFIS
Changes in taxonomic and functional composition of subalpine plant communities in response to climate change under contrasting conditions of bedrock and snow cover duration
Questions: We assessed interactions between climate change, bedrock types and snow cover duration on the trajectories of taxonomic and functional composition of subalpine plant communities. We predict (i) an increase in species richness on siliceous bedrock due to a reduced competition and a decrease in richness on calcareous bedrock due to increasing drought stress; (ii) decreasing snow cover duration should induce a higher shrub encroachment in hollows as compared to ridges; and (iii) increasing growing season temperature should induce taller sizes and more conservative growth traits, in particular in hollows. Location: Subalpine belt of the Grandes Rousses mountain range, southwestern Alps (France). Methods: 189 vegetation plots were sampled in 1997 and 2017-2018. The duration of snow cover was assessed during two years in 1995-1997 and five functional traits were measured on 108 species in 2021. We performed multivariate analyses, quantified community-weighted means (CWM) of traits and used ANOVAs to detect responses to local-scale factors and changes in snow cover, temperature and precipitation since 1997 according to a nearby meteorological station. Results: Overall, taxonomic composition weakly changed and changes were more dependent on the position of communities along the snow cover duration gradient than on their bedrock type. The abundance of drought-tolerant species increased at the border of hollows and there was, over all communities, a slight increase in the abundance of dwarf shrubs and tall herbaceous species, a strong decrease in short herbaceous species and, thus, an overall decrease in species richness. There were important overall changes in CWM of size traits, in particular leaf area which increased the most in hollows irrespective of bedrock types. Conclusion: In this subalpine site the effects of decreasing snow cover duration overwhelmed the effects of bedrocks, which may explain the overall increase in competitive species and decrease in species richness
(Journal of Vegetation Science. vol. 35, n° 1100-9233, pp. e13253, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LECA, USMB [Université de Savoie] [Université de Chambéry], CNRS, Fédération OSUG, UGA, UR LESSEM, INRAE, Fédération OSUG, UGA
Constraining Plio‐Pleistocene Shifts in Northwest African Hydroclimate, Ecosystem Distributions, and Marine Productivity: New Paleo‐Records Across the Mid‐Pleistocene Transition
AbstractNorthwest Africa transitioned from a wet/vegetated landscape toward drier/sparser conditions sometime between the late‐Pliocene and the late‐Pleistocene. However, our understanding of the precise timing and nature of this transition is hampered by a paucity of paleo‐records which bridge these two intervals. Here we report new plant‐wax isotope as well as dust and opal flux records from the relatively brief interval ∼1.1–1.0 million years ago (Ma) to evaluate the astronomical timescale controls of Northwest African hydroclimate and vegetation during the Mid‐Pleistocene Transition (MPT) and, in context with published records, the drivers of long‐term climate and ecological trends over the Plio‐Pleistocene. The tempo and amplitude of the Northwest African monsoon rainfall swings closely track low latitude insolation forcings over the last 5 Ma. However, we demonstrate that a pronounced mean state decline in monsoon strength likely occurred following the MPT most likely instigated by increasing Atlantic meridional sea surface temperature gradients or declines in the strength of the meridional overturning circulation. The northward extent of vegetation does not track changes in monsoon strength over the Plio‐Pleistocene and thus may be more strongly influenced by changes in monsoon rainfall extent or ecosystem disturbances. Progressively diminished dust fluxes following a decline in monsoon strength after 1.0 Ma is consistent with reduced production and subsequent depletion of fine‐grained sediments in the Sahara. Synchroneity between dust and opal fluxes across timescales suggests nutrient delivery to the surface ocean via dust plays a key role in marine primary productivity off the coast of Northwest Africa.
(Paleoceanography and Paleoclimatology. vol. 39, n° 2572-4525, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
El Niño-like tropical Pacific ocean cooling pattern during the Last Glacial Maximum
Many state-of-the-art climate models are unable to reproduce the observed 20th century surface warming pattern in the tropical Pacific Ocean, casting doubt on the robustness of future projections. Here, we examine past changes in the tropical Pacific upper ocean spatial pattern using paleoclimate reconstructions from proxies and simulations from a multi-model ensemble. The proxy results demonstrate that during the Last Glacial Maximum, when atmospheric carbon dioxide concentrations were lower than present, temperatures in the western tropical Pacific Ocean decreased more than in the east, leading to an El Niño-like cooling pattern. This result contrasts with the zonally uniform cooling pattern observed in model simulations, highlighting the common issue of models overestimating the sensitivity of eastern tropical Pacific sea surface temperatures to greenhouse forcing. Our proxy results imply that the western Pacific may warm more than the east in response to future climate change, producing a La Niña-like surface warming pattern.
(Communications Earth & Environment. vol. 5, n° 2662-4435, pp. 587, 10/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, MARUM, QMUL, NTU