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

Profundiconus is the most divergent cone snail genus and its unique phylogenetic position, sister to the rest of the family Conidae, makes it a key taxon for examining venom evolution and diversity. Venom gland and foot transcriptomes of Profundiconus cf. vaubani and Profundiconus neocaledonicus were de novo assembled, annotated, and analyzed for differential expression. One hundred and thirty-seven venom components were identified from P. cf. vaubani and 82 from P. neocaledonicus, with only four shared by both species. The majority of the transcript diversity was composed of putative peptides, including conotoxins, profunditoxins, turripeptides, insulin, and prohormone-4. However, there were also a significant percentage of other putative venom components such as chymotrypsin and L-rhamnose-binding lectin. The large majority of conotoxins appeared to be from new gene superfamilies, three of which are highly different from previously reported venom peptide toxins. Their low conotoxin diversity and the type of insulin found suggested that these species, for which no ecological information are available, have a worm or molluscan diet associated with a narrow dietary breadth. Our results indicate that Profundiconus venom is highly distinct from that of other cone snails, and therefore important for examining venom evolution in the Conidae family.

KANACONO

The conoidean family Terebridae is an intriguing lineage of marine gastropods, which are of considerable interest due to their varied anatomy and complex venoms. Terebrids are abundant, easily recognizable and widely distributed in tropical and subtropical waters, but our findings have demonstrated that their systematics requires revision. Here we elaborate the classification of Terebridae based on a recently published molecular phylogeny of 154 species, plus characters of the shell and anterior alimentary system. The 407 living species of the family, including seven species described herein, are assigned to three subfamilies: Pellifroniinae new subfamily, Pervicaciinae and Terebrinae. The Pellifroniinae comprises five deep-water species in two genera, Pellifronia and Bathyterebra n. gen. Pellifroniinae possess a radula of duplex marginal teeth, well-developed proboscis and venom gland, and a very small rhynchodeal introvert. The Pervicaciinae includes c. 50 species in the predominantly Indo-Pacific genera Duplicaria and Partecosta. Pervicaciinae possess salivary glands, a radula of solid recurved marginal teeth and a weakly developed rhynchodeal introvert, but lack proboscis and venom gland. The remaining Terebridae species are classified into 15 genera in the subfamily Terebrinae (including four genera described herein); nine genera are defined on the basis of phylogenetic data and six solely on shell morphology. The Indo-Pacific genera Profunditerebra n. gen., Maculauger n. gen. and Myurellopsis n. gen. each include about a dozen species. The first is restricted to the deep waters of the Indo-West Pacific, while the latter two range widely in both geographic and bathymetric distribution. Neoterebra n. gen. encompasses about 65 species from a range of localities in the eastern Pacific, Caribbean, and Atlantic, and from varying depths. To characterize the highly diversified genera Terebra, Punctoterebra, Myurella and Duplicaria, each of which comprise several morphological clusters, we propose the use of DNA-based diagnoses. These diagnoses are combined with more informative descriptions to define most of the supraspecific taxa of Terebridae, to provide a comprehensive revision of the group.

ATIMO VATAE, CONCALIS, EXBODI, INHACA 2011, KARUBENTHOS 2, KARUBENTHOS 2012, KAVIENG 2014, MADEEP, Restreint, MIRIKY, MUSORSTOM 2, NanHai 2014, PANGLAO 2004, PANGLAO 2005, PAPUA NIUGINI, SALOMON 2, SANTO 2006, TERRASSES, Restreint, ZhongSha 2015

Abstract The molluskan order Neogastropoda encompasses over 15,000 almost exclusively marine species playing important roles in benthic communities and in the economies of coastal countries. Neogastropoda underwent intensive cladogenesis in the early stages of diversification, generating a “bush” at the base of their evolutionary tree, which has been hard to resolve even with high throughput molecular data. In the present study to resolve the bush, we use a variety of phylogenetic inference methods and a comprehensive exon capture dataset of 1817 loci (79.6% data occupancy) comprising 112 taxa of 48 out of 60 Neogastropoda families. Our results show consistent topologies and high support in all analyses at (super)family level, supporting monophyly of Muricoidea, Mitroidea, Conoidea, and, with some reservations, Olivoidea and Buccinoidea. Volutoidea and Turbinelloidea as currently circumscribed are clearly paraphyletic. Despite our analyses consistently resolving most backbone nodes, 3 prove problematic: First, the uncertain placement of Cancellariidae, as the sister group to either a Ficoidea-Tonnoidea clade or to the rest of Neogastropoda, leaves monophyly of Neogastropoda unresolved. Second, relationships are contradictory at the base of the major “core Neogastropoda” grouping. Third, coalescence-based analyses reject monophyly of the Buccinoidea in relation to Vasidae. We analyzed phylogenetic signal of targeted loci in relation to potential biases, and we propose the most probable resolutions in the latter 2 recalcitrant nodes. The uncertain placement of Cancellariidae may be explained by orthology violations due to differential paralog loss shortly after the whole genome duplication, which should be resolved with a curated set of longer loci.

ATIMO VATAE, AURORA 2007, BIOMAGLO, BIOPAPUA, CORSICABENTHOS 1, DongSha 2014, EXBODI, ILES DU SALUT, INHACA 2011, KANACONO, KANADEEP, KARUBENTHOS 2, KAVIENG 2014, KOUMAC 2.1, KOUMAC 2.3, MADEEP, MADIBENTHOS, MAINBAZA, NanHai 2014, PAPUA NIUGINI, TAIWAN 2013, Tuhaa Pae 2013, ZhongSha 2015

Predator-prey interactions are thought to play a driving role in animal evolution, especially for groups that have developed venom as their predatory strategy. However, how the diet of venomous animals influences the composition of venom arsenals remains uncertain. Two prevailing hypotheses to explain the relationship between diet and venom composition focus on prey preference and the types of compounds in venom, and a positive correlation between dietary breadth and the number of compounds in venom. Here, we examined venom complexity, phylogenetic relationship, collection depth, and biogeography of the Terebridae (auger snails) to determine if repeated innovations in terebrid foregut anatomy and venom composition correspond to diet variation. We performed the first molecular study of the diet of terebrid marine snails by metabarcoding the gut content of 71 terebrid specimens from 17 species. Our results suggest that the presence or absence of a venom gland is strongly correlated with dietary breadth. Specifically, terebrid species without a venom gland displayed greater diversity in their diet. Additionally, we propose a revision of the definition of venom complexity in conoidean snails to more accurately capture the breadth of ecological influences. These findings suggest that prey diet is an important factor in terebrid venom evolution and diversification and further investigations of other understudied organisms, like terebrids, are needed to develop robust hypotheses in this area.

PAPUA NIUGINI

Central to the discovery of neuroactive compounds produced by predatory marine snails of the superfamily Conoidea (cone snails, terebrids, and turrids) is identifying those species with a venom apparatus. Previous analyses of western Pacific terebrid specimens has shown that some Terebridae groups have secondarily lost their venom apparatus. In order to efficiently characterize terebrid toxins, it is essential to devise a key for identifying which species have a venom apparatus. The findings presented here integrate molecular phylogeny and the evolution of character traits to infer the presence or absence of the venom apparatus in the Terebridae. Using a combined dataset of 156 western and 33 eastern Pacific terebrid samples, a phylogenetic tree was constructed based on analyses of 16S, COI and 12S mitochondrial genes. The 33 eastern Pacific specimens analyzed represent four different species: Acus strigatus, Terebra argyosia, T. ornata, and T. cf. formosa. Anatomical analysis was congruent with molecular characters, confirming that species included in the clade Acus do not have a venom apparatus, while those in the clade Terebra do. Discovery of the association between terebrid molecular phylogeny and the occurrence of a venom apparatus provides a useful tool for effectively identifying the terebrid lineages that may be investigated for novel pharmacological active neurotoxins, enhancing conservation of this important resource, while providing supplementary information towards understanding terebrid evolutionary diversification.

EBISCO, PANGLAO 2004, PANGLAO 2005, SANTO 2006

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

ATIMO VATAE

Devising a reproducible approach for species delimitation of hyperdiverse groups is an ongoing challenge in evolutionary biology. Speciation processes combine modes of passive and adaptive trait divergence requiring an integrative taxonomy approach to accurately generate robust species hypotheses. However, in light of the rapid decline of diversity on Earth, complete integrative approaches may not be practical in certain species-rich environments. As an alternative, we applied a two-step strategy combining ABGD (Automated Barcode Gap Discovery) and Klee diagrams, to balance speed and accuracy in producing primary species hypotheses (PSHs). Specifically, an ABGD/Klee approach was used for species delimitation in the Terebridae, a neurotoxin-producing marine snail family included in the Conoidea. Delimitation of species boundaries is problematic in the Conoidea, as traditional taxonomic approaches are hampered by the high levels of variation, convergence and morphological plasticity of shell characters. We used ABGD to analyze gaps in the distribution of pairwise distances of 454 COI sequences attributed to 87 morphospecies and obtained 98 to 125 Primary Species Hypotheses (PSHs). The PSH partitions were subsequently visualized as a Klee diagram color map, allowing easy detection of the incongruences that were further evaluated individually with two other species delimitation models, General Mixed Yule Coalescent (GMYC) and Poisson Tree Processes (PTP). GMYC and PTP results confirmed the presence of 17 putative cryptic terebrid species in our dataset. The consensus of GMYC, PTP, and ABGD/Klee findings suggest the combination of ABGD and Klee diagrams is an effective approach for rapidly proposing primary species proxies in hyperdiverse groups and a reliable first step for macroscopic biodiversity assessment.

ATIMO VATAE, AURORA 2007, BIOPAPUA, BOA1, EBISCO, EXBODI, MIRIKY, PANGLAO 2004, PANGLAO 2005, SALOMON 2, SANTO 2006, TERRASSES, Restreint

Abstract How species diversification occurs remains an unanswered question in predatory marine invertebrates, such as sea snails of the family Terebridae. However, the anatomical disparity found throughput the Terebridae provides a unique perspective for investigating diversification patterns in venomous predators. In this study, a new dated molecular phylogeny of the Terebridae is used as a framework for investigating diversification of the family through time, and for testing the putative role of intrinsic and extrinsic traits, such as shell size, larval ecology, bathymetric distribution, and anatomical features of the venom apparatus, as drivers of terebrid species diversification. Macroevolutionary analysis revealed that when diversification rates do not vary across Terebridae clades, the whole family has been increasing its global diversification rate since 25 Ma. We recovered evidence for a concurrent increase in diversification of depth ranges, while shell size appeared to have undergone a fast divergence early in terebrid evolutionary history. Our data also confirm that planktotrophy is the ancestral larval ecology in terebrids, and evolutionary modeling highlighted that shell size is linked to larval ecology of the Terebridae, with species with long-living pelagic larvae tending to be larger and have a broader size range than lecithotrophic species. Although we recovered patterns of size and depth trait diversification through time and across clades, the presence or absence of a venom gland (VG) did not appear to have impacted Terebridae diversification. Terebrids have lost their venom apparatus several times and we confirm that the loss of a VG happened in phylogenetically clustered terminal taxa and that reversal is extremely unlikely. Our findings suggest that environmental factors, and not venom, have had more influence on terebrid evolution.

ATIMO VATAE, EXBODI, INHACA 2011, KARUBENTHOS 2, KAVIENG 2014, MADEEP, MAINBAZA, MIRIKY, NanHai 2014, PANGLAO 2005, SALOMON 2, SANTO 2006, TERRASSES, ZhongSha 2015

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

A revision of the terebrid genus Granuliterebra (Oyama, 1961), is carried out, a new terebrid genus, Pellifronia n. gen., and three new terebrid species, Granuliterebra oliverai n. sp., G. eddunhami n. sp., and Myurella lineaperlata n. sp. Are described from the Vanuatu Archipelago. Conchological characters were used in the analysis of specimens gathered from two recent major expeditions to the Vanuatu Archipelago by the Museum national d'Histoire naturelle. A total of 106 terebrid species in the bathymetrical range of 0-200 m, representing the Philippines, New Caledonia and Vanuatu were used in a comparative study. There is a 65% overlap of the terebrid fauna found in Santo and in the Philippines and New Caledonia.

BORDAU 1, LIFOU 2000, MUSORSTOM 10, MUSORSTOM 6, MUSORSTOM 8, PANGLAO 2004, PANGLAO 2005, SANTO 2006

Partecosta milesi sp. nov. is described as new and compared to its sole morphological congener in the SW Indian Ocean. The South African members of the genus Gradaterebra are revised of which knowledge of the shell morphology remains only peripheral.

ATIMO VATAE