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Sea pens (Cnidaria: Anthozoa: Pennatulacea) constitute a distinctive group of colonial marine invertebrates. They inhabit the world`s oceans, from shallow to deep waters. Studies about this group in Argentina are scarce, and no species have been described in the area in over a decade. Based on samples collected in Mar del Plata Submarine Canyon at about 3000 m deep we describe a new species of sea pen, Umbellula pomona Risaro, Williams & Lauretta sp. nov. This is a spiculate Umbellula that differs from other species of Umbellula with sclerites, by the number, development and distribution of the autozooids in its terminal cluster, as well as the shape of its axis. Molecular data also distinguishes it from other known species. Of the forty-three described species approximately ten are considered valid for the genus Umbellula, four of them are registered for the South Atlantic Ocean and only three are described for the Antarctic region. Since sampling efforts in this area have been scarce, the number of species of sea pens from the region is likely to increase substantially in the coming years.
In the vast abyssal plains northwest of Iceland, white glass sponges of the genus Caulophacus Schulze, 1886 were inhabited by reddish Bythocaris G.O. Sars, 1870 shrimps and pinkish amphipods. After in situ observations at 3700 m depth, in -1°C waters by a remotely operated vehicle, members of this assemblage were collected and preserved for molecular studies. Based on integrative taxonomic analyses, the amphipods were identified as a new species of the genus Halirages Boeck, 1871 – Halirages spongiae sp. nov. Lörz, Nack & Tandberg –, as described in detail below. Part of our integrative approach was to establish reference DNA barcodes for known species of Halirages. However, our investigation of material of Calliopiidae G.O. Sars, 1895 collected around Iceland and Norway revealed slight morphological discrepancies in all the described species of Halirages. Except for Halirages fulvocinctus (M. Sars, 1858), none of the encountered specimens of Calliopiidae fully matched a current species description. We illuminate the morphological characteristics of nine operational taxonomic units, which also represented clades in COI and 28S. We set the Icelandic samples in the context of Halirages from Canada and Norway. A key to the world species of Halirages is provided.
Die Rotatorienfauna einiger Gewässer des Naturschutzgebietes „Heiliges Meer“ im Kreis Steinfurt
(2001)
Die planktontische und die benthische Rotatorienfauna des NSG Heiliges Meer, Krs. Steinfurt, Nordrhein-Westfalen, wurde durch monatliche Beprobung von eutrophen, oligotrophen und dystrophen Gewässern zwischen Oktober 1999 und Oktober 2000 untersucht. Insgesamt konnten 195 Rädertierarten festgestellt werden, davon waren 166 Monogononta und 29 Bdelloidea.
An illustrated checklist of the Mollusca of Galicia Bank, a large and deep seamount off the NW Iberian Peninsula, is provided. The studied material was collected in 8 samples of Seamount 1 cruise (1987), 7 samples of ECOMARG 0709 (2009) and 36 samples of BANGAL 0711 (2011), between 615 and 1768 m. A total of 212 species are known to occur at the Galicia Bank (1 Monoplacophora, 7 Solenogastres, 3 Polyplacophora, 132 Gastropoda, 54 Bivalvia, 6 Scaphopoda, and 9 Cephalopoda), 21 of which from previous studies only. Four species are described as new, 34 species are first record in Spanish waters and another 20 species first record for the Northern Spanish waters. Over 7500 specimens, representing 104 species, were collected alive, and 87 species were represented by empty shells only. Only 53 species were detected in both Seamount 1 and BANGAL 0711; most of the species are rare and more species can be expected if exploration is continued. There is a marked difference in species composition between the summit platform (615‒1000 m) and the deeper part below 1500 m, with some genera (e.g., Colus and Limopsis) represented by alternative species. Endemism, if any, is very low and most of the species are widespread.
Responses of southern ocean seafloor habitats and communities to global and local drivers of change
(2021)
Knowledge of life on the Southern Ocean seafloor has substantially grown since the beginning of this century with increasing ship-based surveys and regular monitoring sites, new technologies and greatly enhanced data sharing. However, seafloor habitats and their communities exhibit high spatial variability and heterogeneity that challenges the way in which we assess the state of the Southern Ocean benthos on larger scales. The Antarctic shelf is rich in diversity compared with deeper water areas, important for storing carbon (“blue carbon”) and provides habitat for commercial fish species. In this paper, we focus on the seafloor habitats of the Antarctic shelf, which are vulnerable to drivers of change including increasing ocean temperatures, iceberg scour, sea ice melt, ocean acidification, fishing pressures, pollution and non-indigenous species. Some of the most vulnerable areas include the West Antarctic Peninsula, which is experiencing rapid regional warming and increased iceberg-scouring, subantarctic islands and tourist destinations where human activities and environmental conditions increase the potential for the establishment of non-indigenous species and active fishing areas around South Georgia, Heard and MacDonald Islands. Vulnerable species include those in areas of regional warming with low thermal tolerance, calcifying species susceptible to increasing ocean acidity as well as slow-growing habitat-forming species that can be damaged by fishing gears e.g., sponges, bryozoan, and coral species. Management regimes can protect seafloor habitats and key species from fishing activities; some areas will need more protection than others, accounting for specific traits that make species vulnerable, slow growing and long-lived species, restricted locations with optimum physiological conditions and available food, and restricted distributions of rare species. Ecosystem-based management practices and long-term, highly protected areas may be the most effective tools in the preservation of vulnerable seafloor habitats. Here, we focus on outlining seafloor responses to drivers of change observed to date and projections for the future. We discuss the need for action to preserve seafloor habitats under climate change, fishing pressures and other anthropogenic impacts.
Until now, only 177 species of sponges (Porifera) have been reported for Chilean coastal waters. Here we describe recent scuba diving surveys undertaken to improve our knowledge of the diversity of the sponge fauna of the Seno Magdalena, Puyuhuapi Fjord and Jacaf Canal in Chilean Patagonia. Despite these relatively harsh environments, our study yielded 23 species of Demospongiae, nine of which are new to science and described here: Hymerabdia imperfecta Bertolino, Costa & Pansini sp. nov., Axinella cylindrica Bertolino, Costa & Pansini sp. nov., Axinella coronata Bertolino, Costa & Pansini sp. nov., Biemna aurantiaca Bertolino, Costa & Pansini sp. nov., Biemna erecta Bertolino, Costa & Pansini sp. nov., Biemna typica Bertolino, Costa & Pansini sp. nov., Scopalina cribrosa Bertolino, Costa & Pansini sp. nov., Rhizaxinella strongylata Bertolino, Costa & Pansini sp. nov. and Darwinella pronzatoi Bertolino, Costa & Pansini sp. nov. One species, Hymedesmia (Stylopus) lissostyla (Bergquist & Fromont, 1988), is reported for the first time for Chile.