The detailed study of arm ossicles, particularly the lateral arm plates, is providing valuable information in the elucidation of ophiuroid taxonomy. The present study describes in detail 16 species of brittle stars from Araçá Bay, Brazil. This information is used to construct the first interactive electronic key, providing a valuable resource for a broad range of researchers. Brittle stars families were divided into three groups based on their spatial distribution: i) infaunal species of intertidal and shallow subtidal belonging to Amphiuridae and Ophiactidae, ii) epizoic species belonging to Amphiuridae, Ophiactidae, and Ophiotrichidae and, iii) epifaunal species of the subtidal belonging to Ophiodermatidae and Hemieuryalidae. In the global context of recent revisions of ophiuroid taxonomy, the present work provides additional characters for use in future phylogenetic studies.

A new genus and species of Kinorhyncha, Franciscideres kalenesos gen. et sp. nov., is described from tidal and subtidal sandy habitats in Brazil. The new genus and species is characterized by an extremely flexible trunk without pachycycli that appears perfectly circular in cross-section, segments 1, 2 and 11 consisting of closed rings and 3 to 10 of single, bent plates with midventral articulations, a neck without placids that resembles an additional segment, densely packed scale-like, cuticular hairs, and a terminal segment with a middorsal spine and two sets of lateral terminal spines, but no midterminal spine. Phylogenetic analyses of 18S rRNA of Franciscideres kalenesos gen. et sp. nov. and 47 other kinorhynch ingroup taxa suggest that the new genus is a basal homalorhagid, whereas comparison of morphological characters indicates affinities between the new genus and the peculiar cyclorhagid Cateria.http://zoobank.org/urn:lsid:zoobank.org:pub:64E29D97-DE1D-4511-8683-C969DD2EED43

Although sea turtles have received substantial focus worldwide, research on the immature life stages is still relatively limited. The latter is of particular importance, given that a large proportion of sea turtle populations comprises immature individuals. We set out to identify knowledge gaps and identify the main barriers hindering research in this field. We analyzed the perceptions of sea turtle experts through an online survey which gathered their opinions on the current state of affairs on immature sea turtle research, including species and regions in need of further study, priority research questions, and barriers that have interfered with the advancement of research. Our gap analysis indicates that studies on immature leatherback Dermochelys coriacea and hawksbill Eretmochelys imbricata turtles are lacking, as are studies on all species based in the Indian, South Pacific, and South Atlantic Oceans. Experts also perceived that studies in population ecology, namely on survivorship and demography, and habitat use/behavior, are needed to advance the state of knowledge on immature sea turtles. Our survey findings indicate the need for more interdisciplinary research, collaborative efforts (e.g. data-sharing, joint field activities), and improved communication among researchers, funding bodies, stakeholders, and decision-makers.

Protodrilidae is a group of small, superficially simple-looking annelids, lacking chaetae and appendages, except for two prostomial palps. Originally considered to be one of the primitive "archiannelid" families, its affinity within Annelida is still highly debated. Protodrilids are found worldwide in the interstices of intertidal and subtidal marine sediments. Despite their simple appearance they constitute one of the most species-rich interstitial families, with 36 described species in two genera, Protodrilus and the gutless Astomus. Here we present the first phylogenetic study of Protodrilidae employing five gene fragments, 55 morphological characters and 73 terminals (including seven outgroups) analysed under direct optimization and parsimony as well as model-based methods. The large data set includes all 36 described species of Protodrilidae (17 of which are represented only by the morphological partition) as well as 30 undescribed or uncertain species (represented by both morphology and molecules). This comprehensive, inclusive and combined analysis revealed a new perspective on the phylogeny of Protodrilidae: the family is shown to contain six cosmopolitan subclades, each supported by several morphological apomorphies, and with the genus Astomus consistently nested among the other five clades rather than next to these. Consequently, the diagnosis of Protodrilus is emended, Astomus remains unchanged and the four remaining lineages are diagnosed and named Megadrilus n. gen, Meiodrilus gen. nov., Claudrilus n. gen and Lindrilus gen. nov. Character transformations showed that large size and presence of pigmentation, oviducts and eyes are plesiomorphies of the family, retained in Protodrilus, Megadrilus gen. nov. and Lindrilus gen. nov. These features are secondarily lost in the gutless Astomus with epidermal uptake of nutrients, as well as in Meiodrilus gen. nov. and some species of Claudrilus n. gen, with smaller size correlated to life in interstices of finer sediments.

Worsaae, K. (2013). Evolution of cave Axiokebuita and Speleobregma (Scalibregmatidae, Annelida). --Zoologica Scripta, 42, 623-636. The evolutionary history of Axiokebuita and Speleobregma, two poorly known lineages of annelids exclusive from deep-sea or marine caves but always from crevicular habitats, is explored here. Speleobregma lanzaroteum Bertelsen, 1986, and Axiokebuita cavernicola sp. n. are described from anchialine and marine caves of the Canary Islands using light and electron microscopy. Speleobregma lanzaroteum is previously known only from a single specimen from the water column of an anchialine cave in Lanzarote. Emended diagnosis, details on the ciliary patterns and behavioural observations are provided based on newly collected material and in situ observations. Axiokebuita cavernicola sp. n. is found in Pleistocene gravel deposits in a shallow water marine cave in Tenerife (Canary Islands). The new species is characterized by the presence of dorsal ciliary bands and short knob-like neuropodial cirri from segment two. The porosity and permeability of the gravelly environment of A. cavernicola sp. n. are shown to be equivalent to the water column or crevices of Speleobregma and other Axiokebuita spp. Phylogenetic analyses of five gene fragments and 44 terminals using maximum-likelihood and Bayesian methods support a derived position of A. cavernicola sp. n. within Axiokebuita and confirm a sister-group relationship of Axiokebuita with Speleobregma with high nodal support. The Axiokebuita-Speleobregma clade is morphologically characterized by a globular pygidium with adhesive glands and ventral ungrooved ciliated palps. Our results support two independent cave colonization events, favoured by the preadaptation of the members of Axiokebuita-Speleobregma lineage to crevicular habitats.

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Accurate assessments of biodiversity are crucial to advising ecosystem-monitoring programs and understanding ecosystem function. Nevertheless, a standard operating procedure to assess biodiversity accurately and consistently has not been established. This is especially true for meiofauna, a diverse community (>20 phyla) of small benthic invertebrates that have fundamental ecological roles. Recent studies show that metabarcoding is a cost-effective and time-effective method to estimate meiofauna biodiversity, in contrast to morphological-based taxonomy. Here, we compare biodiversity assessments of a diverse meiofaunal community derived by applying multiple taxonomic methods based on comparative morphology, molecular phylogenetic analysis, DNA barcoding of individual specimens, and metabarcoding of environmental DNA. We show that biodiversity estimates are strongly biased across taxonomic methods and phyla. Such biases affect understanding of community structures and ecological interpretations. This study supports the urgency of improving aspects of environmental high-throughput sequencing and the value of taxonomists in correctly understanding biodiversity estimates.