Marine Biodiversity

The Nannastacidae of the deep south-eastern Atlantic obtained during the German expedition DIVA II and the French expeditions ZAIANGO and BIOZAIRE 1 to 3 were analysed. Thirteen more frequently occurring nannastacid species were found, including seven new deep-sea species and a new genus from the Cape, Angola and Guinea Basins: Campylaspides armatus sp. n., Bathypicrocuma ifrmer gen. and sp.n., Styloptocuma dentatum sp. n. , S. cuspidatum sp. n., S. paucidentatum sp. n., Styloptocuma enigma sp. n., and Thalycrocuma barbatulum sp. n. The species Procampylaspis lucida and Campylaspis serratocarinata had already been described for the Angola Basin but remained in open nomenclature. After their rediscovery, they were now named. The species Styloptocuma minimum, S. pleonserratum and Platycuma lineata were already known from the Angola Basin and were now rediscovered in the Cape and Guinea Basins. The species Atlantocuma tenuis was already known as widespread in the Atlantic. The most speciose genus in the family Nannastacidae described here is Styloptocuma with six species, four of which are new.

Studies suggest that Pleistocene sea-level fluctuations have drastically affected shallow marine ecosystems such as coral reefs. In the Southwest Atlantic, a Seamounts chain near the Abrolhos Bank has been hypothesized as a stable climatic refugium during the Last Glacial Maximum (LGM). This refugium would have allowed recolonization of the present-day shoreline. Here, we integrated paleoclimatic simulations based on ecological niche modeling (ENM) and adopted a phylogeographic approach to assess this hypothesis for the endemic reef-building coral Mussismilia braziliensis. The niche modeling indicated that the potential distribution of M. braziliensis was smaller in the LGM than in the present; however, the predicted climatically stable regions were not located in the Victoria–Trindade seamount chain, but in regions to the north of this chain. Genetic data showed low structure for the three markers used: SRP-54, ITS, and MaSC-1. Our results suggest a scenario in which the M. braziliensis distribution probably followed the sea-level fluctuation, maintaining its latitudinal distribution range since the LGM, and that it was not confined to a reduced climatic refugium, as previously imagined. We highlight the pioneering nature of this study by combining phylogeography and paleoclimate modeling in order to clarify historical processes that resulted in the current scleractinian biodiversity of Brazilian reefs.

The present study reports the occurrence of several specimens of the penaeid shrimp Penaeus notialis in the Gulf of Cadiz (Spain). The southern pink shrimp is a penaeid originating from east and west Atlantic tropical coastal waters. New observations of tropical species in temperate waters have increased in the last 20 years. This species may have been able to expand successfully northward to European waters, probably favored by global warming, although an accidental introduction by ballast waters cannot be completely discarded. The widespread presence of African biota such as P. notialis in the Gulf of Cadiz ecosystem underscores the necessity of establishing a long-term monitoring program that focuses on this and other currently established non-native species.

Uncertainty surrounding the number and identity of species of genus Limacia O.F. Müller, 1781, in southern African and European coastal waters presents an ongoing conundrum. Limacia clavigera (O.F. Müller, 1776) was previously thought to be the only species of its genus in the eastern Atlantic, with a distribution covering north- to south-eastern Atlantic waters. In the light of more recent molecular and morphological research, several distinct lineages have been uncovered in both Europe and southern Africa. Here, we gathered this information and included additional specimens from the two regions to produce an integrative morphological and molecular framework in which to delineate species. Molecular data of mitochondrial genes cytochrome oxidase subunit I and the large ribosomal subunit (16S rRNA) were amplified to perform molecular phylogenetic- and species-delimitation analyses. Findings led to the discovery and description of one new species from Europe: Limacia inesae sp. nov., three new species from southern Africa: Limacia jellyi sp. nov., Limacia miali sp. nov., and Limacia langavi sp. nov., and the confirmation of the validity of Limacia lucida (Stimpson, 1855) from southern Africa. Species-specific distributional and ecological traits further support species distinctions and historical biogeographical processes behind the inferred evolutionary relationships are further explored.

The life cycle of the anthoathecate hydroid Zanclea sessilis (Gosse, 1853) (Cnidaria: Hydrozoa: Zancleidae), symbiotic with colonies of the cheilostomate bryozoan Turbicellepora magnicostata (Barroso, 1919) (Bryozoa: Gymnolaemata), was investigated in the laboratory using material collected in the Basque Country (Spain, southeast of the Bay of Biscay), and its medusae were reared to maturity. The gastrozooids, dactylozooids and the newly released and adult medusae are described and depicted, including their cnidome. The feeding behaviour of the medusae in the cultures is described. The colonies have polymorphic hydranths, and gastrozooids and dactylozooids can be distinguished. The latter are described for the first time in this hydroid, and have been known in the genus Zanclea Gegenbaur, 1857 only in species from the Indo-Pacific. Dactylozooids were observed only once in colonies in the field, although they developed occasionally in colonies kept in aquaria on their original substrate. The interaction between the hydroid and the bryozoan is considered a facultative mutualistic cooperation, as both species can live without forming an association. This interaction is common in the study area, as, in some shallow water environments, up to 65 % of the colonies of T. magnicostata host Z. sessilis.

Flyingfishes are large enough to eat zooplankton, small enough to be consumed by top predators, and therefore form a central mid-trophic component of tropical epipelagic marine food webs. Characterizing patterns of flyingfish abundance, distribution, and habitat preference has important implications for understanding both localized and generalized functions of marine ecosystems. The eastern tropical Pacific Ocean (ETP) supports many flyingfish species and their predators, yet no studies to date have identified oceanographic factors that define flyingfish habitats or estimate species richness and diversity at broad taxonomic and geographic scales. In this study, we analyzed 11,125 flyingfish representing 25 species and all seven named genera, collected from the ETP over a 21-year period. We applied spatially explicit analysis methods (ARCGIS, DIVA-GIS, MAXENT) and compared specimen locality data to remotely sensed oceanographic data and previously described oceanographic partitions. Our results show that Exocoetus is the most abundant genus (49%) and E. monocirrhus the most abundant species (32%) of flyingfishes in the ETP. Mean sea surface temperature was most important for defining flyingfish habitats (19.2–41.7%) and species richness (highest in the North Equatorial Current). Additionally, flyingfish species diversity was found to be highest in coastal regions of the study area (Shannon indices > 1.5). Together, these results provide unprecedented characterizations of a mid-trophic epipelagic community in an economically valuable region during a time when sea surface temperatures are predicted to increase as a result of global climate change.

We report in situ observations that reveal the presence of the thorid genus Eualus at hydrothermally active sites. The shrimp Eualus amandae Nye, Copley & Linse, 2013 was first collected in non-venting sites but near areas of hydrothermal activity, on the East Scotia Ridge segment E9 and in the Kemp Caldera, South Sandwich Arc. During a recent expedition of RV Polarstern, specimens of Eualus amandae were observed via a remotely operated vehicle (ROV) at the East Scotia Ridge segment E2 and Kemp Caldera. The animals were seen in shimmering water sites on pillow basalts and at active hydrothermal orifices, both unambiguously hydrothermally active. These sites were also characterised by other vent marginal fauna, such as deep-water comatulid crinoids or stoloniferean cnidarians. The shrimp family Thoridae is more diverse in Antarctic waters than other shrimp families and these records suggest two independent origins of hydrothermal-related habitats in Lebbeus, and now Eualus. These records expand the understanding of the contribution of geothermal activity to larger patterns of Antarctic deep-sea biodiversity.