Gaidropsarus mauritanicus (Gadiformes, Gaidropsaridae) a new three-bearded rockling from a deep-water coral ecosystem with a genetically verified biogeographical distribution of the genus and notes to its ecology and behavior.

Gaidropsarus mauritanicus sp. nov. is described from one specimen collected using a grab sample from the Tanoûdêrt Canyon (ca. 20° N) off Mauritania at a depth of 595 m. The new species was further observed during eight remotely operated vehicle (ROV) dives along the Mauritanian slope southwards down to the Tiguent Coral Mound Complex (~17° N) in a bathymetric range between 613 and 416 m. It can be distinguished from congeners by a combination of characteristics, including large eyes (38.1% head length [HL]), large head (25.8% standard length [SL]), elongated pelvic fins (35.7% SL), low number of vertebrae (44), and coloration (pinkish with a dorsal darker brownish hue and bright blotches along the dorsal-fin base). A species-delimitation analysis performed with available cytochrome c oxidase subunit 1 (COI) sequences affiliated to the genus Gaidropsarus additionally supported the validity of the new species. Video analyses showed a deep-water coral-associated and protection-seeking behavior, which may explain why the species has remained undescribed until now. Additional ROV footage from separate deep-water coral sites in the North Atlantic and Mediterranean Sea further highlights the ecological behavior and hidden diversity of bathyal three-bearded rocklings. Here, we additionally discuss the biogeographical distribution of all genetically verified Gaidropsarus spp. in combination with genetic data and morphological characters. G. mauritanicus sp. nov. is closely related to a species from Tasmania (43° S), a geographical point furthest among the studied samples, which may hint to an important influence of (paleo-) oceanography on the distributions of Gaidropsarus species.

Unexpected deep-sea fish species on the Porcupine Bank (NE Atlantic): Biogeographical implications.

Four specimens corresponding to three rare deep-water fish species were caught on the Porcupine Bank (Northeast Atlantic) in September 2019. These catches include the new northernmost records of Azores rockling Gaidropsarus granti and deep-water dab Poecilopsetta beanii in the Atlantic Ocean and the second record of the latter species in its eastern zone. Three of the specimens were retained and their molecular identification also allowed the Cataetyx alleni DNA barcode to be obtained for the first time. The appearance of P. beanii, a West Atlantic species, in its eastern zone is discussed in relation to a possible phenomenon of transoceanic drift in the larval stage.

Geographic range expansion of Ephippion guttifer (Tetraodontidae) in the north-eastern Atlantic.

The first record of the prickly puffer Ephippion guttifer (Tetraodontidae) from Galician waters (north-west Spain) is reported based on a male specimen of 570 mm total length (LT ) caught in the Ría de Vigo. Morphometric, meristic and DNA barcode data confirmed the identification. Histological examination of reproductive tissue was carried out in this species for the first time, showing a mature male in an actively spawning phase. A historical revision invalidates a previous record and establishes this as the northernmost confirmed capture ever reported in the north-eastern Atlantic Ocean.

Microplastics and cellulosic microparticles in North Atlantic deep waters and in the cold-water coral Lophelia pertusa.

This study explores microplastic and cellulosic microparticle occurrences in the NE Atlantic, focusing on the Porcupine Bank Canyon and Porcupine Seabight. Water samples from depths ranging between 605 and 2126 m and Lophelia pertusa coral samples from 950 m depth were analysed. Microparticles were detected in deep-water habitats, with concentrations varying from 2.33 to 9.67 particles L-1 in the Porcupine Bank Canyon, notably lower at greater depths. This challenges the assumption of deeper habitats solely acting as microplastic sinks. We also found evidence of microparticle adsorption and ingestion by L. pertusa. The presence of microparticles in cold-water corals underscores their vulnerability to pollutants. Furthermore, the dominance of rayon microparticles in both water and coral samples raises questions about marine pollution sources, potentially linked to terrestrial origins. This research emphasises the critical need for comprehensive exploration and conservation efforts in deep-sea environments, especially to protect vital ecosystems like L. pertusa reefs.

Non-indigenous species of Bryozoa from anthropogenic habitats in the Bay of Cádiz (South Iberian Peninsula).

Samples of bryozoans collected from two localities in the Bay of Cádiz with different levels of anthropogenic impact are studied. A total of 25 species was identified, of which 8 are considered non-indigenous (NIS), 12 as native and 5 cryptogenic. A new species of Hippopodina, Hippopodina similis sp. nov., is here described, and corrections to the diagnosis of the genus are proposed. The species appears to be a recent immigrant in Cádiz, although it could also be present in the eastern Mediterranean. Aeverrilla setigera and the genus Hippopodina itself are recorded for the first time in the eastern Atlantic. Anguinella palmata is recorded for the first time in Spanish waters. Amathia vidovici was already recorded in the Iberian Peninsula, but previous records should be confirmed. Other species, such as Amathia verticillata, Biflustra tenuis, Watersipora subatra and Schizoporella errata, were already recorded in the Bay of Cádiz very recently.

PAHs and trace metals in marine surficial sediments from the Porcupine Bank (NE Atlantic): A contribution to establishing background concentrations.

Little is known about pollutant concentrations in marine remote areas such as the Porcupine Bank in the NE Atlantic Ocean. Remote locations are much less studied than the more readily accessible coastal areas, nevertheless, are of great importance both to unveil how far human influence has reached and, are more challenging, to infer background concentrations (BCs) of naturally occurring and/or anthropogenic pollutants. Knowledge of contaminant background levels are critical for establishing remediation and management strategies; in addition, background assessment is heavily emphasised in legislative monitoring requirements. Obtaining suitable sampling locations to assess background concentrations can be challenging, as samples should match characteristics to the target area and not be impacted by historical or current inputs of the chemical substances of study. Anthropogenic impacts generally deem local-based sampling to be unsuitable to infer background pollution values. Sampling in remote areas such as the Porcupine Bank better fulfils low impact and pressure requirements making them more suitable for the derivation of background concentration estimates for organic compounds and metals. The total concentrations of polycyclic aromatic hydrocarbons (PAHs) and metal(loid)s in deep sea sediments were evaluated and both an environmental status and a set of concentration data were adequate to derive BCs concentrations is presented. Concentration data indicated, in comparison with previous published data, trace level presence of PAHs and metal(loids) in sediments from the Porcupine Bank. These values will provide a valuable tool to identify the natural presence of organic and inorganic compounds and be the basis to perform a sound environmental assessment.

Life History and Fishing Aspects of the Deep-Sea Silver Scabbardfish Lepidopus caudatus in the Azores.

Deep-sea fisheries are of important economic value. Therefore, it is necessary to generate biologically and ecologically based fishing plans to make this fishery sustainable over time. The silver scabbardfish, Lepidopus caudatus, is a worldwide-distributed demersal fish, commercially exploited in the Azores. Despite L. caudatus high landings and discharges in the region, information about its ecology, population structure, biology and fisheries remains little-known. This work analyzed scientific survey and fishery-dependent data from the past 30 years to understand the changes in abundance, spatial distribution and life history of this species. Lepidopus caudatus spatial distribution was associated with depths between 200 and 400 m, close to seamounts and islands, and on sandy bottoms. The size structure varied yearly, and the population was dominated by females (sex ratio, M:F = 0.46:1). Growth rates were between the estimated values in previous studies in the Azores and indicated a slow-grower species (L∞ = 171.62 cm, k = 0.12 year-1, Φ' = 3.52). The abundance indices highlighted a declining tendency, and this result was backed by the high exploitation rate for the fish in the region (E = 0.53). Lack of management measurements and the species' vulnerability could lead to the depletion of this species.

Reproductive Biology of the Sea Cucumber Holothuria mammata (Echinodermata: Holothuroidea).

Holothuria mammata is one of the most valuable species of sea cucumber, as well as one of the main target species harvested in the Mediterranean and NE-Atlantic regions. This study aims to describe the reproductive cycle of H. mammata in a coastal area of southwest Portugal. Monthly samplings were carried out for 19 months, with the concomitant collection of environmental data and biometric data. H. mammata had a sex ratio of 1:1.2 (male:female) and a size at first maturity of 142 mm for males and 167 mm for females. The gonadosomatic index (GI) peaked between April and May for both sexes. Gonad development started when days had a shorter photoperiod (9 to 13 h of sunlight) and lower seawater temperature (<15 °C), and spawning occurred later, with longer photoperiod (13 to 15 h of sunlight) and higher seawater temperature (>15 °C) and chlorophyll-a concentrations. The development of new studies to increase the biological and ecological knowledge of the populations of H. mammata is essential to create conditions for the domestication of broodstock in captivity, to allow the development of fishing regulations based on informed decisions and to create precise measures for the conservation of ecosystems.

Effects of depth and overgrowth of ephemeral macroalgae on a remote subtidal NE Atlantic eelgrass (Zostera marina) community.

We conducted a short-term field sampling complemented with time integrating stable isotope analysis to holistically investigate status and ecological interactions in a remote NE Atlantic Zostera marina meadow. We found high nutrient water concentrations, large biomass of fast-growing, ephemeral macroalgae, low abundance, and biodiversity of epifauna and a food web with thornback ray (Raja clavata) as intermediate and cod (Gadus morhua) as top predator. We observed no variation with increasing depth (3.5-11 m) except for decreasing shoot density and biomass of Zostera and macroalgae. Our results indicate that the Finnøya Zostera ecosystem is eutrophicated. During the past three to four decades, nutrients from aquaculture have steadily increased to reach 75% of anthropogenic input while the coastal top predator cod has decreased by 50%. We conclude that bottom-up regulation is a predominant driver of change since top-down regulation is generally weak in low density and exposed Zostera ecosystems such as Finnøya.

Spatial and ontogenetic variations in sardine feeding conditions in the Bay of Biscay through fatty acid composition.

Food characteristics are amongst the most influential factors determining the fish life history traits as quantitative and qualitative changes in individuals' diet can lead to a decline in the energy allocated to their growth, and hence influence natural populations' characteristics. The size-at-age and weight of European sardines (Sardina pilchardus) in the Bay of Biscay (BoB) have decreased substantially over the last decade, especially for the youngest age classes, and the factors underlying such changes have not yet been identified. We therefore analysed the fatty acid (FA) composition in the neutral (NL) and polar (PL) lipids in samples collected across the BoB to determine whether the diet of sardines changes with their ages. We found that the total FA contents in both lipid fractions varied mainly with the sampling locations and age. Indeed, sardines aged 1 and 2 years living in South BoB had particularly high contents in FA specific to non-diatom phytoplankton, while older sardines living in the Northern part had higher total FA content and more FA specific to copepods. These differences probably resulted from differences in prey availability and to a lesser extend a change in feeding behaviour with age. The strong dependence of younger sardines' diet to phytoplankton in spring suggests that changes in primary production may explain their decline in size-at-age. Finally, NL clearly reflect finest feeding variations in comparison to PL imprinted by diet variations at longer time scale. Future studies should consider separately NL and PL fractions.

Pleistocene expansion, anthropogenic pressure and ocean currents: Disentangling the past and ongoing evolutionary history of Patella aspera Röding, 1798 in the archipelago of Madeira.

AIMS: Rising sea-level following the Last Glacial Maximum lead to fragmentation of coastal limpet populations between islands of the Archipelago of Madeira. This fragmentation is reinforced by recent heavy exploitation reducing effective population size on Madeira Island. We use the limpet P. aspera to understand how the role of processes at different time scales (i.e. changes in the sea level and overexploitation) can influence the genetic composition of an extant species, relating these processes to reproductive phenology and seasonal shifts in ocean currents. LOCATION: Madeira Island, Porto Santo and Desertas (Archipelago of Madeira, NE Atlantic Ocean). TAXON: The limpet Patella aspera. METHODS: Twelve microsatellite genetic markers were used. A power analysis was used to evaluate the power of the microsatellite markers to detect a signal of population differentiation. Long-term past migrations were assessed using a Bayesian Markov Montecarlo approach in the software MIGRATE-n to estimate mutation-scaled migration rates (M = m/µ; m, probability of a lineage immigrating per generation; µ, mutation rate). Two scenarios were evaluated using an Approximate Bayesian Computation (ABC) in the software DIYABC 2.1 (i) Scenario 1: considered a population scenario from a reduced Ne at time t3 to a higher Ne at time t2; and (ii) Scenario 2 considering a reduction of Ne from a time t3 to a time t2. RESULTS: Colonization of the archipelago by Portuguese settlers six centuries ago probably led to an important decrease in the genetic diversity of the species (Ne). Contemporary gene flow strongly support a pattern of high asymmetric connectivity explained by the reproductive phenology of the species and spatio-temporal seasonal changes in the ocean currents. Spatio-temporal reconstructions using Bayesian methods, including coalescent and Approximate Bayesian Computation (ABC) approaches, suggest changes in the migration patterns from highly symmetric to highly asymmetric connectivity with subtle population differentiation as consequence of post-glacial maximum sea level rise during the Holocene. MAIN CONCLUSIONS: Our results suggest that anthropogenic activity could have had serious effects on the genetic diversity of heavily exploited littoral species since the end of the Pleistocene, probably accelerating in recent years.

First report of Labrorostratus caribensis (Annelida, Oenonidae) as endoparasite of Haplosyllis rosenalessoae (Annelida, Syllidae) from Brazil.

In this study, we report the second endoparasitic relationship for the oenonid Labrorostratus caribensis, previously described parasitizing a nereid polychaete. The new host is the syllid Haplosyllis rosenalessoae, in which it occupies 2/3 of its body cavity host. This is the second endoparasitic relationship between polychaetes and the first between both partners in known for Brazil, as well as the first record of the parasite outside the type locality (Caribbean) and of the host in the State of Bahia. We discuss on the interest of the finding of these king of parasitic relationships and provide an identification key to all knwon species of Labrorostratus.

Biochemical Composition and Energy Strategy Along the Reproductive Cycle of Female Octopus vulgaris in Galician Waters (NW Spain).

The common octopus, Octopus vulgaris, has a short life cycle, growing rapidly to maturity, spawning once, and characterized by an asynchronic oocyte development and a synchronic ovulation dying after breeding. This species has a protein and amino acid metabolism and it is usually defined as an income breeder. However, most biochemical studies lack an examination of the whole reproductive cycle, in particular the spawning process. We here studied the biochemical changes and determined the energy strategy along reproduction in female O. vulgaris, and found that proteins were the main energy reserve, primarily located in the body muscle when sexually maturing and decreasing during breeding. Lipids were also an important source of energy in the ovary and digestive gland and decreased during breeding too. By contrast, glycogen had a minor contribution to the energy content and was the unique compound that increased in spawning and post-spawning females. Additionally, the most abundant fatty acids (FA) in all tissues were 16:0, 18:0, 20:1n9, 20:4n6 (ARA), 20:5n3 (EPA) and 22:6n3 (DHA), with a clear predominance of long-chain polyunsaturated FA. The FA profile of mature ovaries was compared with other life stages finding similitudes with eggs, hatchlings and juveniles but considerable differences with paralarvae which showed higher DHA/ARA and EPA/ARA ratios. Therefore, we found important biochemical changes along the reproductive cycle that determined the energetic signature in each tissue, though no significant energy trade-offs between tissues were found, suggesting that, on the one hand, female O. vulgaris obtained energy directly from food accumulated simultaneously in the somatic and reproductive tissues during sexual maturation. However, an energy reallocation from somatic to reproductive growth would occur once vitellogenesis has started, so that the rate at which body growths would decrease in favor of ovary growth. On the other hand, during breeding, a general decrease in the energy content occurred in all tissues, so that the ovary would be responsible for the spawning success, whereas muscle tissues and digestive gland would independently supply the energy needed for the body maintenance safeguarding the female survival needed for the maternal care.

Eusirus bonnieri sp. nov. (Crustacea: Amphipoda: Eusiridae), a new deep species from the southeastern Bay of Biscay (NE Atlantic Ocean).

A new bathyal eusirid, Eusirus bonnieri sp. nov., is described from the SE Bay of Biscay, mainly characterized by its strongly deflexed rostrum (not mentioned for any other known Eusirus species) and by a long spiniform process at the posterodistal corner of pereopods 5-7 merus. It was sampled with a suprabenthic sledge between 370 and 1099 m on southern margin of the Cap Ferret Canyon and within the Capbreton Canyon. It was relatively scarce on the open slope and its maximum abundance was registered within the upper part of the Capbreton canyon. Beside some ecological/biological data, an identification key is provided for all known species in this genus.

A new midshelf record in the northern Bay of Biscay (NE Atlantic, CBT-CS11 core): Sedimentological, geochemical and palynological data over the last 7 kyrs.

The high-time resolution (∼70 years in average) multi-proxy analysis conducted on the mid-shelf core CBT-CS11 (47°46.429'N; 4°25.308'W; 73 m depth; 3.96 m long; NW France, S Brittany) revealed the complexity of the palaeohydrological and palaeoclimatic signals recorded over the last 7 kyrs in the recently published paper: "Oceanic versus continental influences over the last 7 kyrs from a midshelf record in the northern Bay of Biscay (NE Atlantic)" [1]. This study presents the whole CBT-CS11 dataset discussed in [1] including sedimentological (XRF and grain-size (total from [1] and CaCO3-free from [2]) analyses), geochemical (oxygen and carbon stable isotopes on two different benthic foraminiferal species: Ammonia falsobeccarii from [1] and Cibicides refulgens from [2]) analyses) as well as palynological (dinoflagellate cyst and pollen assemblages from [1]) data. The present study also describes the different statistical tests from which ecological groups have been established from palynological indicators in [1].

Identity of bryozoan species described by Jullien Calvet from the Bay of Biscay historically attributed to Smittia.

During the late nineteenth and early twentieth centuries, a number of species of bryozoans were described in the genus Smittia Hincks, 1879 (a junior synonym of a dipteran genus). Jullien and/or Calvet named several species, mainly from the Bay of Biscay. Some of them have been re-examined in recent years and ascribed to Smittina Norman, 1903 and other genera. Five species, however, have remained unstudied. Here, type specimens of S. colletti, S. decipiens, S. fallax, S. gemmata, S. grimaldi and S. immersa-together with new specimens recently collected-are examined. The morphological study of all this material enabled the conclusion that only three species are involved. The synonymy of S. colletti with the senior species Smittina cervicornis is proposed; S. gemmata is transferred to the smittinid genus Raymondcia; and S. fallax, S. grimaldi and S. immersa, together with S. decipiens, are considered as junior subjective synonyms of Porella compressa.

New species and new records of bryozoans from Galicia (NW Spain).

Although the bryozoological fauna of Galicia (NW Spain) is probably the best known of the whole Iberian Peninsula, and perhaps one of the better known in Europe, new studies continue to provide new knowledge. A new species, Schizotheca galaica sp. nov., is described. Eleven species are newly recorded in Galicia: Aetea longicollis, Parellisina curvirostris, Copidozoum planum, Glabrilaria corbula, Haplopoma sciaphilum, Schizomavella (Schizomavella) mamillata, Fenestrulina asturiasensis, Fenestrulina barrosoi, Buffonellaria muriella, Schizotheca divisa and Dentiporella saldanhai; two of them (B. muriella and S. divisa) are also reported for the first time in Iberian waters; four others (Antarctothoa galaica, F. asturiasensis, F. barrosoi and D. saldanhai) are reported for the first time since their original descriptions, and SEM images of A. longicollis and F. asturiasensis are provided for the first time. Moreover, the range of geographical distribution of some species is expanded: the record of S. divisa is the southernmost to date, while the records of S. mamillata, F. barrosoi and D. saldanhai are the most northerly to date. The presence of other four species in Galician waters is confirmed and we document the permanence and range extension of two species recently introduced into our waters (Tricellaria inopinata and A. galaica). urn:lsid:zoobank.org:pub:F8D0ABEF-026E-4FC8-A947-6484249519FA.

Last snails standing since the Early Pleistocene, a tale of Calliostomatidae (Gastropoda) living in deep-water coral habitats in the north-eastern Atlantic.

Three species in the gastropod genus Calliostoma are confirmed as living in Deep-Water Coral (DWC) habitats in the NE Atlantic Ocean: Calliostoma bullatum (Philippi, 1844), C. maurolici (Seguenza, 1876) and C. leptophyma Dautzenberg Fischer, 1896. Up to now, C. bullatum was only known as fossil from Early to Mid-Pleistocene outcrops in DWC-related habitats in southern Italy; our study confirmed its living presence in DWC off Mauritania. A discussion is provided on the distribution of DWC-related calliostomatids in the NE Atlantic and the Mediterranean Sea from the Pleistocene to the present.

Watersiporidae (Bryozoa) in Iberian waters: an update on alien and native species.

Species of the genus Watersipora comprise an important invasive fouling group but are difficult to identify up to species level. This problem, in conjunction with the recent re-description of several member species, requires the revision of previous records and newly collected material in order to more precisely determine their actual presence and distribution. Here, we revise the identity and distribution of alien and native species of Watersiporidae in Iberian waters based on newly collected material, historical collections, and bibliographic data. Four species of Watersipora are now known from here. Watersipora cucullata is the only native species, present in the Spanish Mediterranean. Watersipora subatra seems to have been introduced relatively recently in Iberian and European Atlantic waters and has been expanding to other Atlantic localities. Watersipora arcuata was collected for the first time in Europe at the SW Spanish Atlantic coast in 1990 and recently in Mediterranean marinas. Watersipora souleorum is known in Iberian waters from two localities in the Gulf of Cadiz and in Gibraltar. With the recent redescription of the genus Watersipora, W. complanata is no longer a member. A new watersiporid genus, Terwasipora gen. nov., is described for this species. In Iberian waters, T. complanata comb. nov. is considered a native species, frequent and abundant in shallow waters along the Atlantic coast.

Microplastics in the stomach contents of common dolphin (Delphinus delphis) stranded on the Galician coasts (NW Spain, 2005-2010).

Plastic debris is currently recognised as one of the major global threats to marine life. However, few data exist on the presence and abundance of microplastics (plastics < 5 mm in size) in marine mammals. This is the first record of the presence of microplastics in the digestive tracts of marine mammals from the Iberian Peninsula. This study made use of 35 samples of common dolphin stomach contents. Microplastics were identified in all the samples analysed, an average of 12 items per stomach although abundance varied widely from one stomach to another. Most plastic items were small fibres although some fragments and a bead were also found. Excluding the smallest fibres as possible airborne contamination, the estimated occurrence of microplastics could drop to as low as 94%. Although factors affecting accumulation of microplastics and their effect on common dolphins are unknown, the fact that all stomachs analysed contained microplastics is a cause for concern.