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Monitoring water systems under extreme conditions or in remote areas poses a risk to scientists and staff involved, and can also result in disturbances to the local flora and fauna. In order to overcome these limitations, new techniques are being developed with the aim to gain more insight into how geochemical pathways of trace elements regulate the functioning of the ocean. Here, we present the first trace metals and inorganic nutrients concentrations measured in dissolved (<0.22 µm) surface water samples collected in the Antarctic by using an Automatic Water Autosampler (AWA) system onboard an unmanned aerial vehicle (UAV). The AWA system has been used to chemically quantify the composition of the water masses (lake and coastal water) of Deception Island (South Shetland Islands, Antarctica), with, for example, Pb values ranging from 0.01 to 0.25 nM in seawater and 1.20 to 2.11 nM in lake water. The results demonstrate the effectiveness of the AWA system in environmental studies that require the sampling of trace metals and nutrients without sample contamination.

Monitoring water systems under extreme conditions or in remote areas poses a risk to scientists and staff involved, and can also result in disturbances to the local flora and fauna. In order to overcome these limitations, new techniques are being developed with the aim to gain more insight into how geochemical pathways of trace elements regulate the functioning of the ocean. Here, we present the first trace metals and inorganic nutrients concentrations measured in dissolved (<0.22 µm) surface water samples collected in the Antarctic by using an Automatic Water Autosampler (AWA) system onboard an unmanned aerial vehicle (UAV). The AWA system has been used to chemically quantify the composition of the water masses (lake and coastal water) of Deception Island (South Shetland Islands, Antarctica), with, for example, Pb values ranging from 0.01 to 0.25 nM in seawater and 1.20 to 2.11 nM in lake water. The results demonstrate the effectiveness of the AWA system in environmental studies that require the sampling of trace metals and nutrients without sample contamination.

In this work, we describe a new sponge species belonging to the genus Coelosphaera Thomson, 1873. It was collected during an Argentinean Summer Antarctic Research Cruise onboard the Research Vessel “Puerto Deseado” in March 2014, near South Orkney Islands (Antarctica), 60° 53′ S 42° 35′ W, 487-m depth. Coelosphaera (Coelosphaera) koltuni sp. nov. is a globular, fistular and hollow-shaped sponge, with significantly larger megascleres (almost twice the length) than other Antarctic and New Zealand Coelosphaera species. We provide comparative data of all the described Coelosphaera species, especially those from nearby regions.

Marine viruses are the most abundant biological entities in marine ecosystems, and due to their life cycle’ they have an impact on biogeochemical cycles, contributing in making life possible in the oceans. These days, there is a large and well-established knowledge on what regards to viruses’ role in the marine ecosystems. They influence the particle size distribution, particle sinking rates, bacterial and algal biodiversity, and the release of organic compounds derived from biological metabolism. However, little is known about the influence that the interaction between environmental and biological factors may have on marine viruses’ communities. In Antarctic and the sub-Antarctic waters, phytoplankton blooms occur during the Austral summer, and is then when viruses and bacteria can reach their greatest abundance and activity rates. These algal blooms are usually dominated by different taxonomic groups: diatoms, dinoflagellates, haptophytes, cryptomones, etc. Besides, phytoplankton communities are accompanied by bacterial communities, and they are influenced by environmental conditions. Then, all these interactions may have a role in the function and structure of marine viruses. To test which are the main drivers contributing to shape viral community distribution and structure, four environmentally contrasting locations were sampled during the Austral summer-2015. Three locations were near Orkney and Anvers Islands close to the Antarctic Peninsula, and one in the South Georgia Islands in the sub-Antarctic Ocean. These locations presented different physicochemical and biological conditions (e.g. temperature, salinity, viral and bacterial abundance, phytoplankton taxa...). We characterized the physicochemical conditions and the phytoplankton community of these locations, and we studied the marine viral community structure by using the fingerprint technique: Randomly amplified polymorphic DNA-PCR (RAPD) that allowed to group similar viral communities. Indeed, the four

During the Austral summer 2009 we studied three areas surrounding the Antarctic Peninsula: the Bellingshausen Sea, the Bransfield Strait and the Weddell Sea. We aimed to investigate, whether viruses or protists were the main agents inducing prokaryotic mortality rates, and the sensitivity to temperature of prokaryotic heterotrophic production and mortality based on the activation energy (Ea) for each process. Seawater samples were taken at seven depths (0.1–100 m) to quantify viruses, prokaryotes and protists abundances, and heterotrophic prokaryotic production (PHP). Viral lytic production, lysogeny, and mortality rates of prokaryotes due to viruses and protists were estimated at surface (0.1–1 m) and at the Deep Fluorescence Maximum (DFM, 12–55 m) at eight representative stations of the three areas. The average viral lytic production ranged from 1.0 ± 0.3 × 107 viruses ml−1 d−1 in the Bellingshausen Sea to1.3 ± 0.7 × 107 viruses ml−1 d−1 in the Bransfield Strait, while lysogeny, when detectable, recorded the lowest value in the Bellingshausen Sea (0.05 ± 0.05 × 107 viruses ml−1 d−1) and the highest in the Weddell Sea (4.3 ± 3.5 × 107 viruses ml−1 d−1). Average mortality rates due to viruses ranged from 9.7 ± 6.1 × 104 cells ml−1 d−1 in the Weddell Sea to 14.3 ± 4.0 × 104 cells ml−1 d−1 in the Bellingshausen Sea, and were higher than averaged grazing rates in the Weddell Sea (5.9 ± 1.1 × 104 cells ml−1 d−1) and in the Bellingshausen Sea (6.8 ± 0.9 × 104 cells ml−1 d−1). The highest impact on prokaryotes by viruses and main differences between viral and protists activities were observed in surface samples: 17.8 ± 6.8 × 104 cells ml−1 d−1 and 6.5 ± 3.9 × 104 cells ml−1 d−1 in the Weddell Sea; 22.1 ± 9.6 × 104 cells ml−1 d−1 and 11.6 ± 1.4 × 104 cells ml−1 d−1 in the Bransfield Strait; and 16.1 ± 5.7 × 104 cells ml−1 d−1 and 7.9 ± 2.6 × 104 cells ml−1 d−1 in the Bellingshausen Sea, respectively. Furthermore, the rate of lysed cells and PHP showed higher sensitivity to

Misophrioid copepods are reported for the first time from Antarctic waters. A species of each of the genera Misophriopsis and Misophriella is described from hyperbenthic layers of the continental shelf of the eastern Weddell Sea. The genus Misophria is also reported from these waters. Misophriopsis australis sp. nov. is the fifth representative of this widely distributed genus, previously reported from the North Atlantic, the China Sea, and both NW and NE quadrants of the Pacific Ocean. Misophriella schminkei sp. nov. is the second representative of the genus, known to date only from a single female caught in North Atlantic bathyal depths. Traces of subdivisions on antennary exopodal segments of the latter species suggest that the first segment may be a triple segment, while the second and terminal segments may be double segments. In addition, the mandibular exopod of this taxon indicates that a six-segmented ramus with setal formula 0, 1, 1, 1, 1, 2 may represent the ground pattern in Copepoda. The presence of parts of a cyclopinid copepod in the gut of M. schminkei sp. nov. indicates that this species may be carnivorous

[EN] Nine species of siphonophores were collected during the Belgian† Magga Da? Expedition in a transect from South Africa to Antarctic waters between December 1966 and February 1967. Two species were recorded for the first time in Antarctic waters: Bargmannia elongata and Nanomia bijuga. The bracts of Thalassophyes crystallina were found and described from material collected during this expedition. Two substantial colonies of Mica micula allowed a redescription of species and its systematic position is discussed, [ES] En la campaña «Magga Dan», se muestreó un transecto de estaciones desde Sudáfrica hasta la Antártida entre diciembre de 1966 y febrero de 1967. Se recolectaron nueve especies de sifonóforos de las cuales dos se dan a conocer por primera vez en aguas antárticas y se describe también la bráctea de Thalassophyes crystallina. La recolección de dos colonias de Mica micula ha permitido redescribir esta especie con mayor detalle y comentar su posición sistemática