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New data on the taxonomic composition and distribution of rare deep-sea species of the Bathylagidae, Microstomatidae, and Opisthoproctidae (Argentiniformes) collected off northeastern Brazil, including the Rocas Atoll, the Fernando de Noronha Archipelago, and seamounts off Rio Grande do Norte State are provided. Collections were made by the French RV Antea during the ABRACOS 2 (Acoustics along the BRAzilian COaSt) expedition, between April 9 and May 6, 2017. Among the six species of argentiniforms identified, three are reported for the first time in Brazilian waters: Xenophthalmichthys danae (Microstomatidae), Opisthoproctus soleatus and Rhynchohyalus natalensis (Opisthoproctidae). Three additional species previously recorded off Brazil have their geographic distributions extended to the northeastern region of the country: Dolicholagus longirostris, Melanolagus bericoides (Bathylagidae), and Winteria telescopa (Opisthoproctidae). Remarks on other species of the Argentiniformes reported in the Brazilian Exclusive Economic Zone are also provided. A total of 11 genera and 14 species of the order are confirmed to occur in the region. [ABSTRACT FROM AUTHOR]

Marine bioinvasions are potential threats to biodiversity and ecosystems services, being one of the major environmental, human health and socio-economic problems throughout the world. In 2005, a sponge species never reported before to the Atlantic Ocean was detected in Rio de Janeiro (Brazil). This species was initially considered new to science and in less than a decade its populations became very abundant and widespread in the Brazilian coast. In the present work, we performed detailed morphological and molecular analyses of this supposedly new species and found out that it is in fact the Indo-Pacific calcareous sponge Heteropia glomerosa (Bowerbank, 1873). Heteropia glomerosa is the third alien species of calcareous sponge reported in the Atlantic and the second one that allegedly came from the Indo-Pacific. To confirm the taxonomic identification of the Atlantic specimens, we used morphological and molecular tools and re-described the holotypes of H. glomerosa and Uteopsis argentea (Poléjaeff, 1883). We discuss the possibility that biofouling is the introduction source for sponges and present the known distribution of H. glomerosa. Moreover, we verified that H. glomerosa fits seven out of 10 criteria proposed for recognizing alien species. Although this species can be recognized as introduced in the Atlantic Ocean, studies on population genetics, phylogeography, reproduction strategies, larval behaviour, and ecology will be necessary to allow a better evaluation of its invasive potential. [ABSTRACT FROM AUTHOR]

Abstract: A two-year long record from a triangular mooring array between the Lesser Antilles islands Tobago, Barbados, and St. Lucia is used to investigate the inflow into the Caribbean Sea, the amount of South Atlantic Water (SAW) carried with the inflow, and the role of North Brazil Current (NBC) rings in the observed variability. The data set consists of time series from temperature/conductivity recorders and current meters in the moorings, bottom-mounted inverted echo sounders at the Tobago and St. Lucia mooring positions, and supplementary shipboard measurements. The acoustic travel time measurements of the inverted echo sounders and the conductivity/temperature time series are used for continuous estimation of dynamic height profiles and geostrophic currents between the surface and 1000dbar as well as the amount of SAW found at the mooring positions. The observations show a domination of intraseasonal variability between 0 and 15Sv, superimposed on the long-term fluctuations. With time scales of one to three months, these represent the signature of the NBC rings. The baroclinic transport time series shows nine periods of increased variability, indicative of the rings interacting with the Lesser Antilles island arc; with the exception of one, these periods were associated with corresponding sea surface height anomalies. No marked seasonality was observed in the transport variability or the ring frequency. The arrival of individual rings leads to a weakening of the inflow into the Caribbean. Nevertheless, the rings carry large amounts of SAW into the area, and the immediate increase of the transport towards the end of a ring event suggests a subsequent flow of this SAW-rich water into the Caribbean. At St. Lucia, rings sometimes cause a short-term decrease of SAW content, indicative of an influx of northern hemispheric water and a blocking situation. The average transport of SAW into the Caribbean south of St. Lucia during the observations amounted to 5.5Sv, with no significant seasonal cycle, but a small positive trend in SAW fraction as well as in transport of about 15% and 1Sv, respectively; a corresponding trend in the baroclinic volume transport was not observed. [Copyright &y& Elsevier]

• North Brazil Undercurrent (NBUC) and Current (NBC) are important AMOC pathway. • Using ADCP we finely describe the NBUC-NBC characteristics at two seasons. • We propose a comprehensive picture of NBUC-NBC spatial patterns and transition. • We show how mesoscale activity can impact the surface nearshore circulation. In the tropical Atlantic Ocean, the North Brazil Undercurrent (NBUC) and the North Brazil Current (NBC) play important roles as near-surface northward paths for the Atlantic meridional overturning circulation. To investigate the meridional evolution of the near-surface western boundary circulation in that region, two surveys were carried out off Northeast Brazil during austral spring 2015 and fall 2017, periods that we show to be representative of typical conditions for the spring and fall seasons. Using conductivity temperature depth oxygen probe and ship-mounted acoustic Doppler current profiler measurements, altimetry data, and numerical reanalysis products, we examine the spatiotemporal variability of the NBUC, providing a comprehensive view of the circulation, including NBUC-NBC transition and the potential impact of mesoscale eddies. The NBUC originating south of 10°S flows equatorward over the continental slope. NBUC mean velocity, transport and vertical extent of the velocity core were higher in spring 2015 (0.81 m s−1, 15.6 Sv, and >400 m) than in fall 2017 (0.65 m s−1, 11.0 Sv, and ~300 m). The upper limit of the NBUC velocity core rose slightly from 160 m at 9°S to 105 m depth at 6°S. This pattern is associated with a northward increase in current velocity from 0.7 m s−1 at 9°S to 1 m s−1 at 5°S. The orographic effect shifts the flow from northeastward south of 7.5°S to northwestward north of 7.5°S, following the shoreline. Besides, altimetry data show that this flow can be locally influenced by mesoscale activity. Farther north, at ~4.8°S, data obtained in fall 2017 show that the central branch of the South Equatorial Current (cSEC) enters into the western boundary system where it coalesces with the NBUC to form the NBC, flowing toward the Caribbean Sea. Finally, in fall, the NBUC retroflection does not feed the South Equatorial Undercurrent (SEUC), which, instead originates from retroflections of the cSEC and the equatorial branch of the South Equatorial Current (eSEC). [ABSTRACT FROM AUTHOR]