In this report, we analyze the phylogeny of Pycnogonida using the three nuclear and three mitochondrial markers currently sequenced for studying inter- and intrafamilial relationships within Arthropoda: 18S and 28S rRNA genes, Histone H3, cytochrome c oxidase subunit 1 (CO1), 12S and 16S rRNA genes. We identify several problems in previous studies, due to the use of inappropriate sequences (taxonomic misidentification, DNA contamination, sequencing errors, missing data) or taxa (outgroup choice). Our analyses show that most markers are not powerful to study the phylogeny of sea spiders. The results suggest however a recent diversification of the group (Mesozoic rather than Paleozoic) and the early divergence of Austrodecidae, followed by Colossendeidae. Pycnogonidae and Rhynchothoracidae. Except Ammotheidae and Callipallenidae, all other families were recovered as monophyletic. Analyses of synonymous sites in CO1 sequences reveal an extreme heterogeneity of nucleotide composition within sea spiders, as six unrelated species show a reverse strand-specific bias. We therefore suggest that several independent reversals of asymmetric mutational constraints occurred during the evolution of Pycnogonida, as a consequence of genomic inversions involving either the control region or a fragment containing the CO1 gene. These hypotheses are supported by the comparison of two complete mitochondrial genomes of sea spiders (Achelia bituberculata and Nymphon gracile) with that of Limulus. (C) 2010 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

MUSORSTOM 5, SALOMONBOA 3, SANTO 2006

With over 1600 extant described species, the Muricidae are one of the most species-rich and morphologically diverse families of molluscs. As predators of molluscs, polychaetes, anthozoans barnacles and other invertebrates, they form an important component of many benthic communities. Traditionally, the classification of muricids at specific and generic levels has been based primarily on shells, while subfamilies have been defined largely by radular morphology, although the composition and relationships of suprageneric groups have never been studied exhaustively. Here we present the phylogenetic relationships of 77 muricid species belonging to nine of the ten currently recognized subfamilies, based on Bayesian inference and Maximum Likelihood analyses of partial sequences of three mitochondrial (12S, 16S and COI) and one nuclear (28S) genes. The resulting topologies are discussed with respect to traditional subfamilial arrangements, and previous anatomical and molecular findings. We confirm monophyly of each of the subfamilies Ergalataxinae, Rapaninae, Coralliophilinae, Haustrinae, Ocenebrinae and Typhinae as previously defined, but earlier concepts of Muricinae, Trophoninae and Muricopsinae are shown to be polyphyletic. Based on our phylogenetic hypothesis, a new arrangement of these subfamilies is proposed.

AURORA 2007, CONCALIS, EBISCO, NORFOLK 2, PANGLAO 2004, SANTO 2006

The Glypheidea is a group of lobster-like decapods that appeared in the Triassic and that was thought to be extinct until 1975, when a specimen of the species Neoglyphea inopinata was caught off the Philippines. More recently, in 2005, a specimen of another glypheid species, Laurentaeglyphea neocaledonica, was discovered near New Caledonia. Here, we construct a decapod molecular data set including the two extant glypheid species sequenced from eight nuclear and mitochondrial genes. Our study strongly shows that the two extant genera of glypheids cluster together, and further confirms the status of Glypheidea as a separate infraorder. Moreover the reptantian decapods are divided into two major groups, one including Brachyura, Anomura, and Axiidea, and the other including Astacidea, Polychelida, Achelata, and Glypheidea. Although commonly nicknamed 'Jurassic shrimps' and considered as 'living fossils', glypheids are therefore a derived decapod lineage. (C) 2010 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

EBISCO

The seamounts chain offers a set of fragmented habitats in which species with poor dispersive ability may undergo divergence in allopatry. Such a scenario may explain the endemism often described on seamounts. In gastropods, it is possible to infer the mode of development of a species from the morphology of its larval shell. Accordingly, we examine the population genetics of several caenogastropods from the Norfolk and Lord Howe seamounts (south-west Pacific) with contrasting modes of larval development. A prerequisite to our study was to clarify the taxonomic framework. The species delimitation was ruled using an integrative approach, based on both morphological and molecular evidence. Molecular data indicate an unexpected taxonomic diversity within the existing species names. Both the clarification of the taxonomic framework and the importance of the sampling effort allow us to confidently detect cryptic diversity and micro-endemism. These results are discussed in relation to the dispersive capacities of the organisms. (C) 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 420-438.

CONCALIS, EBISCO, NORFOLK 1, NORFOLK 2, TERRASSES

The Terebridae are a diverse family of tropical and subtropical marine, gastropods that use a complex and modular venom apparatus to produce toxins that capture polychaete and enteropneust preys. The complexity of the terebrid venom apparatus suggests that venom apparatus development in the Terebridae could be linked to the diversification of the group and can be analyzed within a molecular phylogenetic scaffold to better understand terebrid evolution. Presented here is a molecular phylogeny of 89 terebrid species belonging to 12 of the 15 currently accepted genera, based on Bayesian inference and Maximum Likelihood analyses of amplicons of 3 mitochondrial (COI, 165 and 12S) and one nuclear (28S) genes. The evolution of the anatomy of the terebrid venom apparatus was assessed by mapping traits of six related characters: proboscis, venom gland, odontophore, accessory proboscis structure, radula, and salivary glands. A novel result concerning terebrid phylogeny was the discovery of a previously unrecognized lineage, which includes species of Euterebra and Duplicaria. The non-monophyly of most terebrid genera analyzed indicates that the current genus-level classification of the group is plagued with homoplasy and requires further taxonomic investigations. Foregut anatomy in the family Terebridae reveals an inordinate diversity of features that covers the range of variability within the entire superfamily Conoidea, and that hypodermic radulae have likely evolved independently on at least three occasions. These findings illustrate that terebrid venom apparatus evolution is not perfunctory, and involves independent and numerous changes of central features in the foregut anatomy. The multiple emergence of hypodermic marginal radular teeth in terebrids are presumably associated with variable functionalities, suggesting that terebrids have adapted to dietary changes that may have resulted from predator-prey relationships. The anatomical and phylogenetic results presented serve as a starting point to advance investigations about the role of predator-prey interactions in the diversification of the Terebridae and the impact on their peptide toxins, which are promising bioactive compounds for biomedical research and therapeutic drug development. (c) 2012 Elsevier Inc. All rights reserved.

ATIMO VATAE, BOA1, CONCALIS, EBISCO, MAINBAZA, MIRIKY, Restreint, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SANTO 2006, Restreint, TARASOC, TERRASSES

Characterizing speciation processes in the sea remains a highly contentious issue because geographic barriers to gene exchange, which are the initial conditions for the allopatric speciation model, are not obvious. Moreover, many benthic marine organisms have long-lived planktonic larvae that allow them to connect distant patches of habitats. We here analyse the pattern of speciation in the gastropod genus Bursa in which all species have long-lived and planktonic-feeding larvae. We use a large taxonomic and ecologic coverage of Bursidae from the Indo-Pacific. We use an integrative approach to taxonomy to give more support to available taxonomic hypotheses. This analysis revealed cryptic lineages and suggest that a taxonomic revision of the family should be performed. A molecular clock calibrated from the fossil record was used to estimate divergence times. We then focus on the three co-existing species living in the deep waters of New Caledonia. Over the wide sampled area, no genetic structure was detected for the three species. We show that among New Caledonia species, Bursa fijiensis and Bursa quirihorai are reciprocally monophyletic. These two species are the two more closely related species in the inferred phylogeny. The present biogeographic ranges of the two species and the estimated time of divergence make the scenario of geographic isolation followed by secondary contact unlikely.

AURORA 2007, CONCALIS, EBISCO, MAINBAZA, MIRIKY, NORFOLK 1, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 2, TERRASSES

CEAMARC-AA

Toxoglossate marine gastropods, traditionally assigned to the families Conidae, Terebridae, and Turridae, are one of the most populous animal groups that use venom to capture their prey. These marine animals are generally characterized by a venom apparatus that consists of a muscular venom bulb and a tubular venom gland. The toxoglossan radula, often compared with a hypodermic needle for its use as a conduit to inject toxins into prey, is considered a major anatomical breakthrough that assisted in the successful initial radiation of these animals in the Cretaceous and early Tertiary. The pharmacological success of toxins from cone snails has made this group a star among biochemists and neuroscientists, but very little is known about toxins from the other Toxoglossa, and the phylogeny of these families is largely in doubt. Here we report the first molecular phylogeny for the Terebridae and use the results to infer the evolution of the venom apparatus for this group. Our findings indicate that most of the genera of terebrids are polyphyletic, and one species ("Terebra" (s.l.) jungi) is the sister group to all other terebrids. Molecular analyses combined with mapping of venom apparatus morphology indicate that the Terebridae have lost the venom apparatus at least twice during their evolution. Species in the genera Terebra and Hastula have the typical venom apparatus found in most toxoglossate gastropods, but all other terebrid species do not. For venomous organisms, the dual analysis of molecular phylogeny and toxin function is an instructive combination for unraveling the larger questions of phylogeny and speciation. The results presented here suggest a paradigm shift in the current understanding of terebrid evolution, while presenting a road map for discovering novel terebrid toxins, a largely unexplored resource for biomedical research and potential therapeutic drug development.

BOA1, EBISCO, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SANTO 2006, Restreint

Bathymodiolin mussels occur at hydrothermal vents and cold seeps, where they thrive thanks to symbiotic associations with chemotrophic bacteria. Closely related genera Idas and Adipicola are associated with organic falls, ecosystems that have been suggested as potential evolutionary 'stepping stones' in the colonization of deeper and more sulphide-rich environments. Such a scenario should result from specializations to given environments from species with larger ecological niches. This study provides molecular-based evidence for the existence of two mussel species found both on sunken wood and bones. Each species specifically harbours one bacterial phylotype corresponding to thioautotrophic bacteria related to other bathymodiolin symbionts. Phylogenetic patterns between hosts and symbionts are partially congruent. However, active endocytosis and occurrences of minor symbiont lineages within species which are not their usual host suggest an environmental or horizontal rather than strictly vertical transmission of symbionts. Although the bacteria are close relatives, their localization is intracellular in one mussel species and extracellular in the other, suggesting that habitat choice is independent of the symbiont localization. The variation of bacterial densities in host tissues is related to the substrate on which specimens were sampled and could explain the abilities of host species to adapt to various substrates.

AURORA 2007, PANGLAO 2005, SANTO 2006

Bathymodiolinae mussels have been used as a biological model to better understand the evolutionary origin of faunas associated with deep-sea hydrothermal vents and cold seeps. Most studies to date, however, have sampled with a strong bias towards vent and seep species, mainly because of a lack of knowledge of closely related species from organic falls. Here we reassess the species diversity of deep-sea mussels using two genes and a large taxon sample from the South-Western Pacific. This new taxonomic framework serves as a basis for a phylogenetic investigation of their evolutionary history. We first highlight an unexpected allopatric pattern and suggest that mussels usually reported from organic falls are in fact poorly specialized with regard to their environment. This challenges the adaptive scenarios proposed to explain the diversification of the group. Second, we confirm that deep-sea mussels arose from organic falls and then colonized hydrothermal vents and cold seeps in multiple events. Overall, this study constitutes a new basis for further phylogenetic investigations and a global systematic revision of deep-sea mussels. (C) 2010 Elsevier Inc. All rights reserved.

AURORA 2007, BOA1, BORDAU 1, EBISCO, PANGLAO 2005, SALOMON 2, SANTO 2006

Cancellariidae, or nutmeg shells, is a family of marine gastropods that feed on the body fluids and the egg cases of marine animals. The 300 or so living species are distributed worldwide, mostly on soft bottoms, from intertidal to depths of about 1000 m. Although they are a key group for the understanding of neogastropod evolution, they are still poorly known in terms of anatomy, ecology and systematics. This paper reports the first mitochondrial multi-gene phylogenetic hypothesis for the group. Data were collected for 50 morphospecies, representative of 22 genera belonging to the three currently recognized subfamilies. Sequences from three genes (12S, 16S and COI) were analyzed with Maximum Likelihood analysis and Bayesian Inference, both as single gene datasets and in two partitioned concatenated alignment. Largely consistent topologies were obtained and discussed with respect to the traditional subfamilial arrangements. The obtained phylogenetic trees were also used to produce Robinson-Foulds supertrees. Our results confirmed the monophyly of the subfamily Plesiotritoninae, while Admetinae and Cancellariinae, as currently conceived, were retrieved as polyphyletic. Based on our findings we propose changes to the systematic arrangement of these subfamilies. At a lower taxonomic rank, our results highlighted the rampant homoplasy of many characters traditionally used to segregate genera, and thus the need of a critical re-evaluation of the contents of many genera (e.g. Nipponaphera, Merica, Sydaphera, Bivetia), the monophyly of which was not recovered.

AURORA 2007, CONCALIS, MAINBAZA, MIRIKY, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SALOMONBOA 3, SANTO 2006

The diversity, ubiquity and prevalence in deep waters of the octocoral family Chrysogorgiidae Verrill, 1883 make it noteworthy as a model system to study radiation and diversification in the deep sea. Here we provide the first comprehensive phylogenetic analysis of the Chrysogorgiidae, and compare phylogeny and depth distribution. Phylogenetic relationships among 10 of 14 currently-described Chrysogorgiidae genera were inferred based on mitochondrial (mtMutS, cox1) and nuclear (18S) markers. Bathymetric distribution was estimated from multiple sources, including museum records, a literature review, and our own sampling records (985 stations, 2345 specimens). Genetic analyses suggest that the Chrysogorgiidae as currently described is a polyphyletic family. Shallow-water genera, and two of eight deep-water genera, appear more closely related to other octocoral families than to the remainder of the monophyletic, deep-water chrysogorgiid genera. Monophyletic chrysogorgiids are composed of strictly (Iridogorgia Verrill, 1883, Metallogorgia Versluys, 1902, Radicipes Stearns, 1883, Pseudochrysogorgia Pante & France, 2010) and predominantly (Chrysogorgia Duchassaing & Michelotti, 1864) deep-sea genera that diversified in situ. This group is sister to gold corals (Primnoidae Milne Edwards, 1857) and deep-sea bamboo corals (Keratoisidinae Gray, 1870), whose diversity also peaks in the deep sea. Nine species of Chrysogorgia that were described from depths shallower than 200 m, and mtMutS haplotypes sequenced from specimens sampled as shallow as 101 m, suggest a shallow-water emergence of some Chrysogorgia species.

TERRASSES

BIOPAPUA, EXBODI, MADEEP, NORFOLK 2, PAPUA NIUGINI, SALOMON 1, SALOMON 2, SMIB 4, TAIWAN 2013, TERRASSES

The superfamily Conoidea is one of the most speciose groups of marine mollusks, with estimates of about 340 recent valid genera and subgenera, and 4000 named living species. Previous classifications were based on shell and anatomical characters, and clades and phylogenetic relationships are far from well assessed. Based on a dataset of ca. 100 terminal taxa belonging to 57 genera, information provided by fragments of one mitochondrial (COI) and three nuclear (28S, 18S and H3) genes is used to infer the first molecular phylogeny of this group. Analyses are performed on each gene independently as well as for a data matrix where all genes are concatenated, using Maximum Likelihood, Maximum Parsimony and Bayesian approaches. Several well-supported clades are defined and are only partly identifiable to currently recognized families and subfamilies. The nested sampling used in our study allows a discussion of the classification at various taxonomical levels, and several genera, subfamilies and families are found polyphyletic.

BOA1, EBISCO, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SANTO 2006

DNA sequences are currently used to propose primary hypotheses of species delimitation, especially when morphological variability is difficult to assess. In an integrative taxonomy framework, these hypotheses are then compared with other characters, such as morphology or geography, to produce robust species delimitations. For this purpose, the cytochrome oxidase subunit I (COI) gene has been sequenced for almost 50 specimens of the genus Benthomangelia, a deep-sea marine gastropod genus, collected in the South-West Pacific. Five genetic groups, displaying low and high genetic distances respectively within and between groups, were defined. COI hypotheses were compared with both the results obtained with the independent nuclear 28S gene and with an elliptic Fourier analysis of the shape of the last whorl of the shell. 28S gene analysis confirmed the same well-supported groups as COI, and elliptic Fourier analysis identified several morphological characters that vary similarly to genetic variability. (C) 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 696-708.

AURORA 2007, BOA1, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SANTO 2006

The superfamily Conoidea is one of the most speciose groups of marine molluses, with almost 700 genera and 10,000 living species. Previous classifications were based on morphological and anatomical characters, but clades and phylogenetic relationships were not well assessed. Information provided by one mitochondrial (COI) and three nuclear (28S, 18S, and H3) genes were used to infer the phylogeny of this group. Data were obtained from more than 100 specimens, belonging to 54 genera, collected during recent cruises in the western Pacific (Philippines, Vanuatu, Norfolk Ridge, and Chesterfield and Solomon Islands). Analyses were performed on each gene independently as well as for a data matrix where all genes were concatenated, using several methods (ML, Parsimony, Bayesian). Some families and subfamilies among Conoidea correspond to well-supported clades uniformly recovered with all genes and all methods, but others appear to be polyphyletic. Several bathyal and abyssal genera are also shown to he polyphyletic. Our results also point out some new phylogenetic relationships at the family, subfamily, and genus levels.

BOA1, EBISCO, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SANTO 2006

During a broad molecular taxonomic and phylogenetic survey of the gastropod superfamily Conoidea, 80 specimens of several species of the genus Gemmuloborsonia were sequenced for the cytochrome c oxidase subunit I gene. The genus, originally established for fossil species from the Plio-Pleistocene of the Philippines, now includes living species from bathyal depths of the Indo-Pacific Oceans. The molecular data demonstrated the presence of five separate entities, while only four ‘morphospecies’ could be isolated by visual examination. The two largest groups, representing separate species from the molecular data, were impossible to distinguish with certainty using shell or anatomical characters. To examine shell morphology in more detail the shape of the last whorl was analysed by Fourier analysis, and the Fourier coordinates were used in canonical variate analysis. The majority of the specimens were separated into two groups, but 21.6% of the specimens were impossible to distinguish by morphological characters. One of these two forms was attributed to the known species Gemmuloborsonia moosai Sysoev & Bouchet, 1996, while the other is described as a new species Gemmuloborsonia clandestina. Bathytoma colorata Sysoev & Bouchet, 2001 is transferred to Gemmuloborsonia on the basis of molecular analysis and radular morphology. Another species, represented in our material by a single specimen, remains undescribed.

AURORA 2007, CHALCAL 2, EBISCO, KARUBAR, MUSORSTOM 8, NORFOLK 2, SALOMON 2, SALOMONBOA 3

The primary purpose of DNA-barcoding projects is to generate an efficient expertise and identification tool. This is an important challenge to the taxonomy of the 21st century, as the demand increases and the expert capacity does not. However, identifying specimens using DNA-barcodes requires a preliminary analysis to relate molecular clusters to available scientific names. Through a case study of the genus Eumunida (Decapoda : Eumunididae), we illustrate how naming molecule-based units, and thus providing an accurate DNA-based identification tool, is facilitated by sequencing type specimens. Using both morphological and unlinked molecular markers (COI and 28S genes), we analysed 230 specimens from 12 geographic areas, covering two-thirds of the known diversity of the genus, including type specimens of 13 species. Most hypotheses of species delimitation are validated, as they correspond to molecular units linked to only one taxonomic name (and vice versa). However, a putative cryptic species is also revealed and three entities previously named as distinct species may in fact belong to a single one, and thus need to be synonymised. Our analyses, which integrate the current naming rules, enhance the a-taxonomy of the genus and provide an effective identification tool based on DNA-barcodes. They illustrate the ability of DNA-barcodes, especially when type specimens are included, to pinpoint where a taxonomic revision is needed.

BIOCAL, CHALCAL 1, KARUBAR, LITHIST, MUSORSTOM 4, MUSORSTOM 6, MUSORSTOM 7, NORFOLK 1, NORFOLK 2, SALOMON 1, SMCB

Accelerating the description of biodiversity is a major challenge as extinction rates increase. Integrative taxonomy combining molecular, morphological, ecological and geographical data is seen as the best route to reliably identify species. Classic molluscan taxonomic methodology proposes primary species hypotheses (PSHs) based on shell morphology. However, in hyperdiverse groups, such as the molluscan family Turridae, where most of the species remain unknown and for which homoplasy and plasticity of morphological characters is common, shell-based PSHs can be arduous. A four-pronged approach was employed to generate robust species hypotheses of a 1000 specimen South-West Pacific Turridae data set in which: (i) analysis of COI DNA Barcode gene is coupled with (ii) species delimitation tools GMYC (General Mixed Yule Coalescence Method) and ABGD (Automatic Barcode Gap Discovery) to propose PSHs that are then (iii) visualized using Klee diagrams and (iv) evaluated with additional evidence, such as nuclear gene rRNA 28S, morphological characters, geographical and bathymetrical distribution to determine conclusive secondary species hypotheses (SSHs). The integrative taxonomy approach applied identified 87 Turridae species, more than doubling the amount previously known in the Gemmula genus. In contrast to a predominantly shell-based morphological approach, which over the last 30 years proposed only 13 new species names for the Turridae genus Gemmula, the integrative approach described here identified 27 novel species hypotheses not linked to available species names in the literature. The formalized strategy applied here outlines an effective and reproducible protocol for large-scale species delimitation of hyperdiverse groups.

AURORA 2007, BOA1, EBISCO, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SALOMONBOA 3, TAIWAN 2004

Molecular data were used to study the diversity of mytilids associated with sunken-woods sampled in the Solomon Islands and discuss the 'wooden steps to deep-sea vent' hypothesis proposed by Distel et al. First, COI data used in a barcoding approach confirm the presence of four distinct species. Analyses of the 18S rDNA and COI dataset then confirmed that these sunken-wood mytilids belonged to a monophyletic group including all species from deep-sea reducing environments. Finally, we analyzed the relationships within this monophyletic group that include the Bathymodiolinae using a COI dataset and a combined analysis of mitochondrial COI and ND4 genes and nuclear rDNA 18S and 28S. Our study supported the 'wooden steps to deep-sea vent' hypothesis: one of the sunken-wood species had a basal position within the Bathymodiolionae, and all described vent and seep mussels included in our analyses were derived taxa within Bathymodiolinae.

SALOMON 2, SANTO 2006

Bathymodiolinae are giant mussels that were discovered at hydrothermal vents and harboring chemosynthetic symbionts. Due to their close phylogenetic relationship with seep species and tiny mussels from organic substrates, it was hypothesized that they gradually evolved from shallow to deeper environments, and specialized in decaying organic remains, then in seeps, and finally colonized deep-sea vents. Here, we present a multigene phylogeny that reveals that most of the genera are polyphyletic and/or paraphyletic. The robustness of the phylogeny allows us to revise the genus-level classification. Organic remains are robustly supported as the ancestral habitat for Bathymodiolinae. However, rather than a single step toward colonization of vents and seeps, recurrent habitat shifts from organic substrates to vents and seeps occurred during evolution, and never the reverse. This new phylogenetic framework challenges the gradualist scenarios from shallow to deep. Mussels from organic remains tolerate a large range of ecological conditions and display a spectacular species diversity contrary to vent mussels, although such habitats are yet underexplored compared to vents and seeps. Overall, our data suggest that for deep-sea mussels, the high specialization to vent habitats provides ecological success in this harsh habitat but also brings the lineage to a kind of evolutionary dead end.

BIOPAPUA