Diversity under a magnifier lens: the case of Typhlotanaidae (Crustacea: Tanaidacea) in the N Atlantic.

Research focusing on 'stout-bodied' typhlotanaids collected from several sites around Iceland and adjacent N Atlantic region has resulted in the description of 15 species new to science, as well as the creation of eight new genera. Typhlotanais eximius Hansen, 1913 is redescribed and transferred to a new genus, while Typhlotanais crassus and Peraeospinosus adipatus are transferred to the genus Larsenotanais. The morphological and the molecular data were combined to consolidate and confirm the validity of the results obtained from both approaches. The polyphyletic nature of the Typhlotanaidae and its serious of its taxonomic diversity are emphasized, although molecular analysis reveals that the 'stout-bodied' Typhlotanaidae form monophyletic clade. Depth and temperature are identified as the main environmental parameters determining the distribution of this group of Typhlotanaidae. Several species are clearly associated with the shelf and upper bathyal of Iceland. The Greenland-Iceland-Faroe Ridge is shown to be a distinct zoogeographical barrier for typhlotanaids inhabiting the deeper slope and abyssal regions around Iceland.

Mislabeling and nomenclatorial confusion of Typhlotanais sandersi Kudinova-Pasternak, 1985 (Crustacea: Tanaidacea) and establishment of a new genus.

Re-examination of historical collections allowed us to resolve the taxonomic status of Typhlotanais sandersi Kudinova-Pasternak, 1985, originally described based on a single specimen from Great-Meteor Seamount. The holotype of this species was considered lost and the species redescribed based on a second specimen from the type locality by Blazewicz-Paszkowycz (2007a), who placed Ty. sandersi on a newly established genus Typhlamia. Thorough morphological analysis of Typhlamia and Typhlotanais species and recently obtained genetic data of typhlotanaids from N Atlantic and NW Pacific waters allow us to conclude that the redescription of Ty. sandersi by Blazewicz-Paszkowycz (2007a) was based on a wrongly labelled specimen that, rather than a type of Ty. sandersi, represents in fact a new species of Typhlamia. The morphological comparison of the type species of Typhlotanais (Ty. aequiremis) with all 'long-bodied' typhlotanaid taxa with rounded pereonites margins (i.e., Typhlamia, Pulcherella, Torquella), and the use of genetic evidence, support the establishment of a new genus to accommodate: Ty. sandersi, Ty. angusticheles Kudinova-Pasternak, 1989, and a third species from N Atlantic waters, that is described here for the first time. Current knowledge on 'long-bodied' typhlotanaids with rounded pereonites is summarised and a taxonomical key for their identification provided.

Muvi schmallenbergi gen. nov., sp. nov. (Crustacea, Tanaidacea) from the southeast Australian coast, with comments on the distribution and habitat preferences of Chondropodinae.

Based on material collected from the shelf off southeast Australia (offshore of Portland), a new genus and new species, Muvi schmallenbergi gen. nov., sp. nov., of the tanaidacean family Metapseudidae, is described. Muvi is distinguishable from other genera within the subfamily Chondropodinae by having equally long antennular flagella. It also differs from other Chondropodinae by a combination of characters such as eyelobes with a group of visual elements, rostrum with smooth lateral edges, pereonites with lateral processes and pleotelson lacking lateral process, antennule article-1 with a single apophysis, maxillule inner lobe well-developed, labial palp bearing three distal setae, cheliped exopod well-developed and setose, pereopod-1 coxa with distinct apophysis, pleopods in five pairs, and uropod basis without apophysis. The genus Deidamiapseudes Sganga & Roccatagliata, 2016 is moved from Chondropodinae (Metapseudidae) to Apseudoidea incertae sedis. An identification key for the genera within Chondropodinae is given, and their distribution is discussed.

Nematode responses to an Arctic sea-ice regime: morphometric characteristics and biomass size spectra.

Body size is one of the most important traits of organisms that affects their behavioral life histories, physiologies, and energy requirements. For sediment-dwelling organisms, such as free-living nematodes, body size is a direct adaptation for living in sediments with a particular particle size, but other environmental factors, e.g., water depth and food availability, directly or indirectly shape nematode morphology. Nevertheless, our knowledge of meiofaunal organisms sizes still lags far behind that of other aquatic fauna, particularly for high-latitude fauna. Therefore, to gain insight into the nematode community size structure, we investigated eight stations located in the seasonal sea-ice zone north of Svalbard (Yermak Plateau, Nansen Basin, and Northern Svalbard shelf) during Arctic spring. Sample locations covered a wide depth gradient, different sea-ice concentrations and subsequent bloom stages. Our study provides previously unavailable data on nematode morphometry for this Arctic region during ecologically important spring to summer transition times. We analyzed nematode biomass, body shape and morphometric attributes, along with respective feeding types and life stage information. Our results show that differences in nematode densities, biomass and allometric attributes most likely reflect differences in the flux of organic material to the seafloor and in the biogeochemical properties of the sediments. Nematode assemblages appeared to respond to spatial gradients in ice cover duration and therefore pelagic productivity from the northern Svalbard shelf to the Yermak Plateau as evidenced by decreasing density, biomass and body size. Considering the entire community, as well as different life stages, average individual body weight decreased northward. Biomass dominance in the lower weight classes and the significantly lower abundance of long and thick morphotype nematodes observed on the Yermak Plateau than in the two other regions were striking. This was in contrast with the assemblage observed on the shelf, where prevailing environmental conditions influenced the presence of other morphotypes - markedly longer and wider organisms. Ongoing changes in sea-ice cover and primary production in the Arctic may significantly affect nematode functioning, as they are expected to have pronounced impacts on nematode morphological characteristics. In this regard, the size-based approach becomes a useful tool for detecting changes in the community and has important implications for predicting the direction of change with regard to benthic productivity.

Integrative systematics and ecology of a new deep-sea family of tanaidacean crustaceans.

A new family of paratanaoidean Tanaidacea - Paranarthrurellidae fam. nov. - is erected to accommodate two genera without family classification (Paratanaoidea incertae sedis), namely Armatognathia Kudinova-Pasternak, 1987 and Paranarthrurella Lang, 1971. Seven new species of Paranarthrurella and two of Armatognathia are described from material taken in different deep-sea areas of the Atlantic and Pacific oceans. The type species of Paranarthrurella - P. caudata (Kudinova-Pasternak, 1965) - is redescribed based on the paratype. The genus Cheliasetosatanais Larsen and Araújo-Silva, 2014 originally classified within Colletteidae is synonymised with Paranarthrurella, and Arthrura shiinoi Kudinova-Pasternak, 1973 is transferred to Armatognathia. Amended diagnoses of Armatognathia and Paranarthrurella genera are given. Choosing characters for distinguishing and defining both genera was supported by Principal Component Analysis. Designation of the new family is supported by molecular phylogenetic analysis of COI and 18S datasets. The distribution of all species currently included in the new family was visualised and their bathymetric distribution analysed.

New species of Typhlotanaidae (Crustacea, Tanaidacea) from the Brazilian coast: genera Hamatipeda, Meromonakantha and Paratyphlotanais, with description of Targaryenella gen. nov.

Benthic samples collected along the Brazilian coast yielded the description of four new species from three genera of Typhlotanaidae: one Hamatipeda (H. prolata), one Meromonakantha (M. mauri) and two Paratyphlotanais (P. apletos and P. bessai). A new genus Targaryenella is erected to accommodate Meromonakantha anarsios and differences between Targaryenella and Meromonakantha are given. This study increases the total number of Tanaidacea species known for Brazil by 8% (50 to 54 species); the family Typhlotanaidae off the coast of Brazil is now represented by four known genera. Identification keys to the three genera are provided.

Deep ocean seascape and Pseudotanaidae (Crustacea: Tanaidacea) diversity at the Clarion-Clipperton Fracture Zone.

Understanding the diversity and spatial distribution of benthic species is fundamental to properly assess the impact of deep sea mining. Tanaidacea provide an exceptional opportunity for assessing spatial patterns in the deep-sea, given their low mobility and limited dispersal potential. The diversity and distribution of pseudotanaid species is characterized here for the Clarion and Clipperton Fractures Zone (CCZ), which is the most extensive deposit field of metallic nodules. Samples were taken from the Belgian, German and French license areas, but also from the APEI 3 (Area of Particular Environmental Interest 3) of the Interoceanmetal consortium associates. The combination of morphological and genetic data uncovered one new pseudotanaid genus (Beksitanais n. gen.) and 14 new species of Pseudotanais (2 of them virtual taxa). Moreover, our results suggest that spatial structuring of pseudotanaid diversity is correlated with deep-sea features, particularly the presence of fractures and seamount chains crossing the CCZ. The presence of geographical barriers delimiting species distributions has important implications for the establishment of protected areas, and the APEI3 protected area contains only one third of the total pseudotanaid species in CCZ. The specimen collection studied here is extremely valuable and represents an important first step in characterizing the diversity and distribution of pseudotanaids within the Tropical Eastern Pacific.

BioTIME: A database of biodiversity time series for the Anthropocene.

MOTIVATION: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene. MAIN TYPES OF VARIABLES INCLUDED: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record. SPATIAL LOCATION AND GRAIN: BioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2). TIME PERIOD AND GRAIN: BioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year. MAJOR TAXA AND LEVEL OF MEASUREMENT: BioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates. SOFTWARE FORMAT: .csv and .SQL.

Systematic and taxonomic observations on the subfamily Synapseudinae Gutu, 1972 and related metapseudid taxa (Crustacea: Tanaidacea: Apseudomorpha), with the erection of a new genus and descriptions of three new species.

The tanaidacean metapseudid subfamily Synapseudinae Gutu is reviewed, partially revised and the type species, Synapseudes minutus Miller, redescribed. As rediagnosed and defined here, the Synapseudinae is restricted to the genera Synapseudes Miller, Vicinisyndes Gutu, and Creefs Stepien Blazewicz-Paszkowycz. The genera Curtipleon Bacescu and Cryptapseudes Bacescu are excluded from this subfamily. Three new species, S. caleyi, S. singularis, and S. hansknechti are described, bringing the number of putative species within the genus to 26. An identification key and table of selected specific characters for the species of Synapseudes are provided. A new monotypic genus, Ronabus, which is placed within the subfamily Metapseudinae Lang, is erected to receive Synapseudes idios Gardiner. The present taxonomic status of subfamilies within the Metapseudidae is briefly assessed.