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The systematics of the marine mollusc family Velutinidae has long been neglected by taxonomists, mainly because their often internal and fragile shells offer no morphological characters. Velutinids are usually undersampled owing to their cryptic mantle coloration on the solitary, social or colonial ascidians on which they feed and lay eggs. In this study, we address the worldwide diversity and phylogeny of Velutinidae based on the largest molecular dataset (313 specimens) to date, accounting for > 50% of the currently accepted genera, coupled with morphological and ecological data. Velutinids emerge as a diverse group, encompassing four independent subfamily-level lineages, two of which are newly described herein: Marseniopsinae subfam. nov. and Hainotinae subfam. nov. High diversity was found at genus and species levels, with two newly described genera (Variolipallium gen. nov. and Pacifica gen. nov.) and ≥ 86 species in the assayed dataset, 58 of which are new to science (67%). Velutinidae show a remarkable morphological plasticity in shell morphology, mantle extension and chromatic patterns. This variability is likely to be the result of different selective forces, including habitat, depth and trophic interactions.

Background Planaxis sulcatus has been touted as a textbook example of poecilogony, with members of this wide-ranging Indo-Pacific marine gastropod said to produce free-swimming veligers as well as brooded juveniles. A recent paper by Wiggering et al. (BMC Evol Biol 20:76, 2020) assessed a mitochondrial gene phylogeny based on partial COI and 16S rRNA sequences for 31 individuals supplemented by observations from the brood pouch of 64 mostly unsequenced individuals. ABGD and bGYMC supported three reciprocally monophyletic clades, with two distributed in the Indo-Pacific, and one restricted to the northern Indian Ocean and Red Sea. Given an apparent lack of correlation between clade membership and morphological differentiation or mode of development, the reported 3.08% maximum K2P model-corrected genetic divergence in COI among all specimens was concluded to represent population structuring. Hence, the hypothesis that phylogenetic structure is evidence of cryptic species was rejected and P. sulcatus was concluded to represent a case of geographic poecilogony. Results Our goal was to reassess the case for poecilogony in Planaxis sulcatus with a larger molecular dataset and expanded geographic coverage. We sequenced an additional 55 individuals and included published and unpublished sequence data from other sources, including from Wiggering et al. Our dataset comprised 108 individuals (88 COI, 81 16S rRNA) and included nine countries unrepresented in the previous study. The expanded molecular dataset yielded a maximum K2P model-corrected genetic divergence among all sequenced specimens of 12.09%. The value of 3.08% erroneously reported by Wiggering et al. is the prior maximal distance value that yields a single-species partition in ABGD, and not the maximum K2P intraspecific divergence that can be calculated for the dataset. The bGMYC analysis recognized between two and six subdivisions, while the best-scoring ASAP partitions recognized two, four, or five subdivisions, not all of which were robustly supported in Bayesian and maximum likelihood phylogenetic analyses of the concatenated and single gene datasets. These hypotheses yielded maximum intra-clade genetic distances in COI of 2.56–6.19%, which are more consistent with hypothesized species-level thresholds for marine caenogastropods. Conclusions Based on our analyses of a more comprehensive dataset, we conclude that the evidence marshalled by Wiggering et al. in support of Planaxis sulcatus comprising a single widespread, highly variable species with geographic poecilogony is unconvincing and requires further investigation in an integrative taxonomic framework.

A coiled shell is the most evident feature of the typical Bauplan of a gastropod mollusc. However, at least 54 families independently evolved an apparently simplified shell morphology: the limpet. Species with this largely uncoiled, depressed shell morphology occur in almost every aquatic habitat and are associated to a number of different lifestyles and diets. The marine gastropod family Capulidae includes 18 recognised genera, the large majority of which are coiled, but with a number of limpet-like species. Capulid shell plasticity is also associated to a broad range of feeding ecologies, from obligate suspension feeders to kleptoparasites. To investigate the evolution of the limpet-like shell in the family Capulidae we performed an ancestral state reconstruction analysis on a time-calibrated phylogenetic tree (COI, 16S, and ITS2) including 16 species representing a good deal of its morphological diversity. Our results identified at least three capulid lineages that independently evolved limpet-like shells, suggesting that a recurrent limpetization process characterizes this family. One of the limpet-like genera was undescribed and was here named Cryocapulus n. gen. We suggest that capulids evolved from a coiled suspension feeder lineage and that the shift to kleptoparasitism, which occurred in the family ancestor, may have represented a strategy to save energy through the exploitation of the water current produced by the host. Probably the major drivers of shell evolution in capulids are related to their ecology, most of them being kleptoparasites, include the shape and the kind of host substrate, and lead to the repeated acquisition of a limpet-like shape.

Species in the family Capulidae (Littorinimorpha: Capuloidea) display a wide range of shell morphologies. Several species are known to live in association with other benthic invertebrates—mostly bivalves and sabellid worms, but also other gastropods—and are believed to be kleptoparasitic filter feeders that take advantage of the water current produced by the host. This peculiar trophic ecology, implying a sedentary lifestyle, has resulted in highly convergent shell forms. This is particularly true for the genus Hyalorisia Dall, 1889, which occurs in deep water in the Caribbean and Indo-West Pacific provinces, with two nominal species recognized so far. Combining morphological, ecological and molecular data, we assessed the diversity of the genus, its phylogenetic position inside the family and its association with its bivalve host, the genus Propeamussium de Gregorio, 1884 (Pectinoidea), resulting in the description of nine new cryptic species. When sympatric, species of Hyalorisia are associated with different host species, but the same species of Propeamussium may be the host of several allopatric species of Hyalorisia.

Three new species of the neogastropod family Raphitomidae Bellardi, 1875, are described from the Croatian waters of the Adriatic Sea: Raphitoma petanii Prkic, Giannuzzi-Savelli & Pusateri n. sp., R. pusaterii Prkic & Giannuzzi-Savelli n. sp. and R. stanici Prkic, Giannuzzi-Savelli & Pusateri n. sp. The new species are diagnosed by teleoconch characters and by genetic data (COI sequences) in an integrative taxonomy framework. They belong to a group of species with microgranules on the external surface of all teleoconch whorls and all three have a multispiral protoconch indicating a planktotrophic larval phase. The first two species are so far known only from material found in Croatia. R. petanii Prkic, Giannuzzi-Savelli & Pusateri n. sp. and R. stanici Prkic, Giannuzzi-Savelli & Pusateri n. sp. are predominantly shallow-water species, whereas R. pusaterii Prkic & Giannuzzi-Savelli n. sp. has been so far collected only from deeper bottoms with presence of the red coral, Corallium rubrum (Linnaeus, 1758). Syntypes of Murex echinatusBrocchi, 1814 are figured and commented.

Herein we revise several Recent Mediterranean species of the rissoid genus Alvania Risso, 1826: Alvania scabra (Philippi, 1844), Alvania sculptilis (Monterosato, 1877), Alvania sororcula Granata-Grillo, 1877, Alvania lucinae Oberling, 1970, Alvania josefoi Oliver & Templado, 2009 and Alvania scuderii Villari, 2017. They represent a rather homogeneous group of morphologically similar species, referred to as the Alvania scabra complex, which includes also some other species from the northeastern Atlantic. We designate a neotype for Rissoa scabra Philippi, 1844 and a lectotype for Rissoa oranica Pallary, 1900 to stabilize the use of the names. Alvania oranica (Pallary, 1900) is confirmed as a synonym of Alvania scabra (Philippi, 1844), and Alvania asperella (Granata-Grillo, 1877) is proposed as a synonym of Alvania sororcula (Granata-Grillo, 1877) [new synonymy]. Finally, we describe one new Mediterranean species: Alvania pizzinii Amati, Smriglio & Oliverio n. sp. from Levanzo Is., Sicily.

Giannuzzi-Savelli, Riccardo, Pusateri, Francesco, Prkić, Jakov, Bartolini, Stefano, Russini, Valeria, Fassio, Giulia, Oliverio, Marco (2020): Revision of Mediterranean and NE Atlantic Raphitomidae (Gastropoda, Conoidea) 8: The genus Leufroyia Monterosato, 1884. Zoosystema 42 (22): 433-473, DOI: 10.5252/zoosystema2020v42a22

Poecilogony is the intraspecific variation in developmental mode, with larvae of different types produced by the same individual, population or species. It is very rare among marine invertebrates, and in gastropods has long been described only in a few opisthobranchs. The physiological and regulatory mechanisms underlying larval evolutionary transitions, such as loss of planktotrophy that occurred repeatedly in many caenogastropod lineages, are still largely unknown. We have studied the inter- v. intraspecific variation in larval development in the north-east Atlantic neogastropod genus Raphitoma Bellardi, 1847, starting with an iterative taxonomy approach: 17 morphology-based Preliminary Species Hypotheses were tested against a COI molecular-distance-based method (ABGD), and the retained species hypotheses were eventually inspected for reciprocal monophyly on a multilocus dataset. We subsequently performed an ancestral state reconstruction on an ultrametric tree of the 10 Final Species Hypotheses, time-calibrated by fossils, revealing that the interspecific changes were planktotrophy > lecithotrophy, and all have occurred in the Pleistocene, after 2.5 million years ago. This is suggestive of a major role played by Pleistocene Mediterranean oceanographic conditions – enhanced oligotrophy, unpredictable availability of water column resources – likely to favour loss of planktotrophy. Within this group of species, which has diversified after the Miocene, we identified one pair of sibling species differing in their larval development, Raphitoma cordieri (Payraudeau, 1826) and R. horrida (Monterosato, 1884). However, we also identified two Final Species Hypotheses, each comprising individuals with both larval developmental types. Our working hypothesis is that they correspond to one or two poecilogonous species. If confirmed by other nuclear markers, this would be the first documentation of poecilogony in the Neogastropoda, and the second in the whole Caenogastropoda. Although sibling species with different developmental strategies may offer good models to study some evolutionary aspects, poecilogonous taxa are optimally suited for identifying regulatory and developmental mechanisms underlying evolutionary transitions.

We used a molecular phylogenetic approach to investigate species delimitation and diversification in the northeastern Atlantic and Mediterranean musseldrills of the Ocinebrina aciculata complex, based on molecular data from topotypical material of many of the nominal taxa. The complex is shown to consist of at least five species: Ocinebrina aciculata (Lamarck, 1822) from the Atlantic and western Mediterranean; O. cf. corallina (Scacchi, 1836) from the central Mediterranean Sea; O. reinai Bonomolo & Crocetta, 2012 from the Tyrrhenian Sea; O. corallinoides Pallary, 1912 from the Gulf of Gabes; and O. aegeensis n. sp. currently known from the Aegean Sea only. The new species is differentiated from the other taxa by very subtle morphological diagnostic features, although it is clearly identified by genetic distance and apomorphic DNA-sequence characters. The identity of Murex corallinus Scacchi, 1836 (type species of Ocinebrina Jousseaume, 1880) could not be defined with certainty, pending genetic comparison of specimens of the â €? large Tyrrhenian morphotype' (corresponding to the neotype, but not assayed herein) with the assayed â €? small morphotype'.

Three species of the neogastropod genus Columbella Lamarck, 1799 are recognised from the northeastern Atlantic and the Mediterranean. One is the common Mediterranean C. rustica (Linnaeus, 1758), with paucispiral protoconch, extending its range in the Atlantic South to Senegal and North to Portugal. Columbella adansoni Menke, 1853, with multispiral protoconch is restricted to the Macaronesian archipelagoes. A third species, also with multispiral protoconch, from West Africa is recognised through molecular methods, and the name C. xiphitella Duclos, 1840 is employed by correcting the original erroneous locality (“Californie”) to Gabon. Except for protoconch features, no major morphological characters are available to separate the three species; however diagnostic species-level differences in specific positions in the cytochrome c oxidase I (COI) sequences are present between all three species.

In marine environments, connectivity among populations of benthic invertebrates is provided primarily by dispersion of larvae, with the duration of pelagic larval phase (PLD) supposed to represent one of the major factor affecting connectivity. In marine gastropods, PLD is linked to specific larval development types, which may be entirely intracapsular (thus lacking a pelagic dispersal), or include a short pelagic lecithotrophic or a long planktotrophic phase. In the present study, we investigated two sibling species of the cosmopolitan neogastropod genus Columbella (commonly known as dove shells): Columbella adansoni Menke, 1853, from the Macaronesian Atlantic archipelagos, with planktotrophic development, and Columbella rustica Linnaeus, 1758, from the Mediterranean Sea, with intracapsular development. We expected to find differences between these two sister species, in terms of phylogeographic structure, levels of genetic diversification and spatial distribution of genetic diversity, if PLD was actually a relevant factor affecting connectivity. By analysing the sequence variation at the cytochrome c oxidase subunit I (COI) in 167 specimens of the two species, collected over a comparable geographic range, we found that Columbella adansoni, the species with planktotrophic development, and thus longer PLD, showed no phylogeographic structure, lower levels of genetic diversity, interpopulational variance lower than the intrapopulational one and no spatial structure in the distribution of the genetic diversity; Columbella rustica, the species with intracapsular development, thus with evidently lower dispersal abilities, showed a clear phylogeographic structure, higher levels of genetic diversity, high interpopulational and low intrapopulational variance, and a clear signature of global spatial structure in the distribution of the genetic diversity. Thus, in this study, two sibling species differing almost only in their larval ecology (and PLD), when compared for their genetic variation showed patterns supporting the hypothesis that PLD is a major factor affecting genetic connectivity. Therefore, it seems reasonable to expect that the ecological attributes of the marine communities - also in terms of the variation in larval ecology of the species involved - are taken into the due consideration in conservation actions, like the design of marine protected areas networks.

In most marine gastropods, the duration of the larval phase is a key feature, strongly influencing species distribution and persistence. Antarctic lineages, in agreement with Thorson's rule, generally show a short pelagic developmental phase (or lack it completely), with very few exceptions. Among them is the ascidian-feeding gastropod family Velutinidae, a quite understudied group. Based on a multilocus (COI, 16S, 28S and ITS2) dataset for 182 specimens collected in Antarctica and other regions worldwide, we investigated the actual Antarctic velutinid diversity, inferred their larval development, tested species genetic connectivity and produced a first phylogenetic framework of the family. We identified 15 Antarctic Molecular Operational Taxonomic Units (MOTUs), some of which represented undescribed species, which show two different types of larval shell, indicating different duration of the Pelagic Larval Phase (PLD). Antarctic velutinids stand as an independent lineage, sister to the rest of the family, with extensive hidden diversity likely produced by rapid radiation. Our phylogenetic framework indicates that this Antarctic flock underwent repeated events of pelagic phase shortening, in agreement with Thorson's rule, yielding species with restricted geographic ranges.

Proteins of the ShK superfamily are characterized by a small conserved domain (ShKT), first discovered in small venom peptides produced by sea anemones, and acting as specific inhibitors of voltage-dependent and calcium-activated K+ channels. The ShK superfamily includes both small toxic peptides and larger multifunctional proteins with various functions. ShK toxins are often important components of animal venoms, where they perform different biological functions including neurotoxic and immunosuppressive effects. Given their high specificity and effectiveness, they are currently regarded as promising pharmacological lead compounds for the treatment of autoimmune diseases. Here, we report on the molecular analysis of ShKT domain containing proteins produced by the Mediterranean vampire snail Cumia reticulata, an ectoparasitic gastropod that feeds on benthic fishes. The high specificity of expression of most ShK transcripts in salivary glands identifies them as relevant components of C. reticulata venom. These ShK proteins display various structural architectures, being produced either as single-domain secretory peptides, or as larger proteins combining the ShKT with M12 or CAP domains. Both ShKT-containing genes and their internal ShKT domains undergo frequent duplication events in C. reticulata, ensuring a high level of variability that is likely to play a role in increasing the range of their potential molecular targets.

We have compiled a complete list of new marine molluscan taxa introduced by Tommaso Allery Di Maria, Marquis of Monterosato (1841–1927). The dates of publication of every single work have been checked against available evidence, and an updated bibliography is also presented. Finally, the type material of all marine taxa expected to be in the collection Monterosato (presently preserved in the Museo Civico di Zoologia in Rome) has been searched in the main collection, and all retrieved specimens have been catalogued. A large majority of the material has been found, representative specimens of each taxon have been illustrated, and remarks on nomenclature and taxonomy have been provided yielding 42 new synonymies, 46 nominal taxa rediscovered, and 6 new combinations.

Cytolytic pore-forming proteins are widespread in living organisms, being mostly involved in both sides of the host–pathogen interaction, either contributing to the innate defense or promoting infection. In venomous organisms, such as spiders, insects, scorpions, and sea anemones, pore-forming proteins are often secreted as key components of the venom. Coluporins are pore-forming proteins recently discovered in the Mediterranean hematophagous snail Cumia reticulata (Colubrariidae), highly expressed in the salivary glands that discharge their secretion at close contact with the host. To understand their putative functional role, we investigated coluporins’ molecular diversity and evolutionary patterns. Coluporins is a well-diversified family including at least 30 proteins, with an overall low sequence similarity but sharing a remarkably conserved actinoporin-like predicted structure. Tracking the evolutionary history of the molluscan porin genes revealed a scattered distribution of this family, which is present in some other lineages of predatory gastropods, including venomous conoidean snails. Comparative transcriptomic analyses highlighted the expansion of porin genes as a lineage-specific feature of colubrariids. Coluporins seem to have evolved from a single ancestral porin gene present in the latest common ancestor of all Caenogastropoda, undergoing massive expansion and diversification in this colubrariid lineage through repeated gene duplication events paired with widespread episodic positive selection. As for other parasites, these findings are congruent with a “one-sided arms race,” equipping the parasite with multiple variants in order to broaden its host spectrum. Overall, our results pinpoint a crucial adaptive role for coluporins in the evolution of the peculiar trophic ecology of vampire snails.

The southernmost record of the Mediterranean nudibranch Felimida elegantula (Philippi, 1844) is reported here. A single specimen, with a colour pattern that hampered an easy morphological identification, was collected at the Kerkennah Islands (Tunisia). DNA-barcoding analysis (with the cytochrome c oxidase subunit I genetic marker) unambiguously confirmed its identification, and radular and anatomical features conformed with those previously described. With this record, the chromatic polymorphism of F. elegantula is demonstrated to be extremely large and the known range of the species is extended to the African coast of Tunisia.

Specimens of the nudibranch genus Calma were observed under boulders at two Croatian localities while feeding on gobiid eggs. Some ambiguous morphological features compared with the original descriptions of the known species of the genus, C. glaucoides and C. gobioophaga hampered easy identification. Genetic data (COI and 16S sequences) confirmed the distinction between the two species of the genus Calma, and allowed unambiguous identification of the Croatian specimens as Calma gobioophaga. This is the first record of this species for the Mediterranean and extends its distribution range remarkably. Finally, the eggs consumed by the Croatian C. gobioophaga specimens have been taxonomically identified by using the 12S rDNA marker as Gobius cobitis.

Jaminia quadridens (Mollusca: Gastropoda: Heterobranchia: Pulmonata: Stylommatophora: Enidae) is a land snail living up to 2400 m above sea level on calcareous meadow slopes. It is widely distributed in Central and Southern Europe, with two subspecies currently recognised (J. quadridens quadridens and J. quadridens elongata). Like other Enidae, the genus Jaminia is sinistrally coiled, whilst the vast majority of gastropods are dextral. Chirality in snails is determined in the early embryonic stages by a single gene with maternal effect. Following the discovery of reversed (dextral) populations in Abruzzi, we investigated the genetic variability of Jaminia quadridens in central and southern Italy. In fact, reversal of chirality is often associated with extremely rapid speciation in snails ("single gene speciation"), as gene flow between opposite chiral morphs can be severely reduced by pre-copula isolation mechanisms. Phylogenetic analyses with different inference methods, haplotype analyses and species delimitation analyses were carried out on cytochtome oxydase subunit I (COI) sequences of 126 Jaminia specimens from central and southern Italy, Sardinia and Provence. Our results suggested a complex framework, with at least five lineages that may represent distinct species, in agreement with biogeographic patterns previously reported for other terrestrial taxa. Southern populations of an ancestral stock probably underwent allopatric speciation while surviving in glacial refugia during the Pleistocene. Colonization of central Italy may be recent, with evidences of current gene flow between populations of a single species, which includes reversed individuals. The appearance of chiral reversal was statistically associated with marginal demes but apparently not related to other biological, ecological or historical factors. As land snails are generally severely affected by habitat degradation, due to their ecological requirements, our results have important implications for conservation. J. quadridens in Italy may comprise a complex of distinct species, mostly with restricted ranges, which may suffer from environmental changes more than a single, widely distributed species would.

The chromodorid nudibranchs Felimare tricolor (Cantraine, 1835), F. fontandraui (Pruvot-Fol, 1951) and F. picta (Shultz in Philippi, 1836) typically show highly variable colour patterns that are misleading for species identification. Their taxonomy has long been confused, and their identification can be difficult if based only on morphological characters. We carried out molecular genetic analyses using the mitochondrial cytochrome c oxidase subunit I (COI) and 16S rDNA markers on Mediterranean samples of these three taxa representing a large part of their range of chromatic variation. Results proved the usefulness of the DNA-barcoding approach in assessing species delimitation in this group, and in identification of specimens with body colours not clear for species recognition. We inferred preliminary phylogenetic relationships among one third of the currently recognised species of Felimare: they indicated with good support sister species relationship among Felimare tricolor and F. fontandraui, and suggested (with low support) potential relationships among F. picta, F. verdensis, F. californiensis and F. agassizi.

The northeastern Atlantic and Mediterranean small mussel drills of the Ocinebrina aciculata complex are here revised and consist of at least 3 species. The type species, Ocinebrina aciculata (Lamarck, 1822), characterized by a slender shell with rounded whorls and primary and secondary spiral cords of approximately similar size, lives throughout the northeastern Atlantic and Mediterranean Sea at depths usually ranging between 0 and 105 m. Its synonymy is here stabilized by a neotype selection for Murex corallinus Scacchi, 1836. Ocinebrina corallinoides Pallary, 1912 (=Ocinebrina buzzurroi Cecalupo and Mariani, 2008, new synonymy), characterized by a strongly elongate and weakly convex shell and primary and secondary spiral cords of approximately similar size, is endemic to the Gulf of Gabès and is here considered a distinct species, pending genetic studies. Ocinebrina reinai n. sp. is here described from the central Mediterranean Sea (where it is sympatric with O. aciculata) on the basis of morphological diagnostic features of shell (rarest presence of labral tooth, commoner presence of infrasutural apertural denticle, dark spots on the ribs and spiral sculpture with differently sized primary and secondary cords and smaller threads) and radula, confirmed by genetic data. Divergence in COI sequences with sympatric samples of O. aciculata ( > 7%), confirm their status as a distinct species. A comparative table reporting diagnostic features of the congeneric species of the complex and those with which the new species was previously misidentified is offered. Se revisa la taxonomía de las pequeñas especies de gasterópodos murícidos del grupo de Ocinebrina aciculata (Lamarck, 1822). Se consideran válidas tres especies, de las que una se describe como nueva. O. aciculata es la especie tipo del género, está caracterizada por una concha alargada, espiras redondeadas, cordones primarios y secundarios aproximadamente del mismo tamaño, y está distribuida en el área del Atlántico noreste y del Mediterráneo, entre 0 y 105 m de profundidad. Para estabilizar su sinonimia se ha seleccionado un neotipo para Murex corallinus Scacchi, 1836. O. corallinoides Pallary, 1912 (=Ocinebrina buzzurroi Cecalupo and Mariani, 2008, nueva sinonimia) es endémica del Golfo de Gabès, y se distingue por su concha muy alargada y poco convexa, con cordones primarios y secundarios aproximadamente del mismo tamaño. Se considera una especie distinta, a la espera de estudios genéticos. O. reinai n. sp. se describe aqui, y se ha encontrado en Mediterráneo central, donde vive simpátrica con O. aciculata, de la que se distingue por caracteres morfológicos de la concha (rara presencia del diente labral, diente apertural infrasutural más frecuente, manchas oscuras en las costas axiales, cordones primarios y secundarios de tamaño diferente) y de la rádula, confirmados por datos genéticos. Las secuencias del gen mitocondrial COI indican una distancia genética con O. aciculata en simpatría de más de 7%, confirmando su estatus de especie distinta. Se presenta una tabla comparativa de las diferencias entre las especies más similares.

Nitric oxide synthase (NOS) has been characterized in several opistobranchs and pulmonates but it was much less investigated in prosobranchs, which include more than 20,000 species and account for most of the gastropod diversity. Therefore, new data from this large group are needed for a better knowledge of the molecular evolution of NOS enzymes in molluscs. This study focused on NOS expressed in the nervous system of the prosobranch neogastropod Stramonita haemastoma. In this study we report compelling evidence on the expression of a constitutive Ca2+/CaM-dependent neuronal NOS in the central and peripheral nervous system. The prevailing neuronal localization of NADPHd activity was demonstrated by NADPHd histochemistry in both central and peripheral nervous system structures. L-arginine/citrulline assays suggested that Stramonita NOS is a constitutive enzyme which is both cytosolic and membrane-bound. Molecular cloning of the full-length Stramonita NOS (Sh-NOS) by reverse-transcription polymerase chain reaction (RT-PCR) followed by 5′ and 3′ RACE showed that Sh-NOS is a protein of 1,517 amino acids, containing a PDZ domain at the N-terminus and sharing similar regulatory domains to the mammalian neuronal NOS (nNOS). Regional expression of the Sh-NOS gene was evaluated by RT-PCR. This analysis showed different expression levels in the nerve ring, the osphradium, the cephalic tentacles, the buccal tissues, and the foot, whereas NOS expression was not found in the salivary glands and the gland of Leiblein. The present data provide a solid background for further studies addressing the specific functions of NO in neogastropods. J. Comp. Neurol. 520:364–383, 2012. © 2011 Wiley Periodicals, Inc.

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.

Oliverio, Marco (2009): Diversity of Coralliophilinae (Mollusca, Neogastropoda, Muricidae) at Austral Islands (South Pacific). Zoosystema 31 (4): 759-789, DOI: 10.5252/z2009n4a2, URL: http://www.bioone.org/doi/abs/10.5252/z2009n4a2

Received 23 July 2014, Revised 3 March 2015, Accepted 7 May 2015, Available online 20 May 2015, Four genetically distinct clades were recently described under the name Dendropoma petraeum, a Mediterranean endemic vermetid gastropod. The aim of this work is to date the processes that drove to the diversification within this taxon and to relate them to the corresponding historical events occurred in the Mediterranean Sea. Sequences from mitochondrial and nuclear markers were obtained from specimens collected in 29 localities spanning over 4000 km across the entire distribution range of D. petraeum species complex. The phylogenetic and coalescent-based analyses confirmed the four well-supported and largely differentiated lineages of D. petraeum, clearly delimited geographically along a west–east axis within the Mediterranean Sea: Western, Tyrrhenian–Sicilian, Ionian–Aegean and Levantine lineages. Divergence time estimates, obtained using a range of known substitution rates for other marine gastropods, indicated two main stages of diversification. In the first period (between 9.5 and 4.5 mya), the ancestral D. petraeum diverged into the current four lineages. The most recent period occurred between 3.72 and 0.66 mya in the late Pliocene–early Pleistocene, and included the main within-lineage diversification events. Therefore, if the divergence time between the major lineages of Dendropoma in the Mediterranean actually predated or coincided with the Messinian Salinity Crisis, then they should have survived to this dramatic period within the Mediterranean, as supported by Bayes Factors model comparison. Conversely, if the divergence started after the crisis, congruent with the idea that no true marine organism survived the Messinian Salinity Crisis, then our results indicate substitution rates of Dendropoma much higher than usual (5.16% per million years for COI, 3.04% for 16S). More recent climate changes seem to have conditioned the demographic history of each lineage differently. While Western and Tyrrhenian–Sicilian lineages both underwent an increase in their effective population sizes from 1.5 to 0.6 mya coinciding with a long interglacial period, the Ionian–Aegean and Levantine lineages showed constant effective population sizes since 2–2.5 mya, suggesting that these eastern lineages might represent small and relict populations surviving the subsequent Quaternary glaciations in isolated refugia., This study was supported by grants CTM2008-00496 and CGL2011-23306 from the Spanish government, and the European Community (FP7) (COCONET, Grant agreement no: 287844).

The ectoparasitic gastropod genusCerithiopsisForbes & Hanley, 1850 was nominally based onMurex tubercularisMontagu, 1803. We have used the DNA barcode COI sequences to assay sympatric samples of morphotypes recently described as distinct species of theCerithiopsis tubercularis-complex. Our results demonstrated that, in the Croatian waters, the gastropods usually calledC. tubercularisin fact comprise a complex of cryptic species, which can be reliably diagnosed only by examining the soft parts. In the present study we have demonstrated that the colour pattern of the head-foot is diagnostic at the species level in this complex and, coupled with genetic data, may provide a sounding base for a revision of the cerithiopsids of the European coasts.

The aeolid nudibranch Caloria elegans (Facelinidae) is quite common in the Mediterranean Sea and eastern Atlantic Ocean and is easily recognized by the presence of a typical black spot at the apical portion of its cerata. Facelina quatrefagesi (Facelinidae) was long considered as a synonym of C. elegans until recently, when it was re-evaluated as a valid species based mainly on rhinophore morphology. In order to definitively assess the status of these aeolid taxa, we employed an integrative taxonomy approach using the nuclear H3 and the two mitochondrial cytochrome oxidase subunit I and 16S markers. The molecular analyses clearly showed that, although morphologically closely related to C. elegans, F. quatrefagesi is a valid species.

The gastropod genus Colubraria includes marine shallow-water species from tropical, subtropical, and temperate rocky coral environments. At least six species are known to feed on fish blood. Although there is general consensus in placing Colubraria in the Neogastropoda, the actual relationships and the systematic position of Colubraria and related genera are unknown. This is partly the consequence of the lack of a clear phylogenetic framework for the Neogastropoda. This study attempts to propose a phylogenetic framework for the Neogastropoda, by testing: (1) a preliminary phylogenetic arrangement for a large number of recognized neogastropod families; (2) the position of Colubraria within the neogastropods; and (3) the relationships of Colubraria within one of the major neogastropod lineages. We used two different molecular data sets. The first set included representatives of at least 14 neogastropod families, for points (1) and (2), and was based on mitochondrial (16S, 12S, and cytochrome oxidase subunit I, COI) and nuclear (28S) DNA sequences, giving a total of 3443 aligned positions. The second data set, for point (3), included 30 buccinoid sequences from mitochondrial 16S, giving a total of 1029 aligned positions. We also studied the anatomy of the type species of Colubraria and compared it with other neogastropods within the new phylogenetic framework. The results included the first phylogeny of the neogastropod based on 50% of the recognized families. This clearly indicated that the nematoglossan Cancellariidae represent a basal offshoot of the monophyletic Neogastropoda, and that the toxoglossan Conoidea are the sister group to the Rachiglossa. Within the Rachiglossa, a colubrariid clade, worthy of family ranking, showed clear buccinoid affinities. Most of the anatomy of Colubraria is congruent with a buccinoid model. The peculiar anatomical features that do not conform to the buccinoid model seem to be related to the evolution of haematophagous feeding. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158, 779–800.

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.

The Mediterranean species of the genus Mitromorpha Carpenter, 1865 as currently conceived, are herein reviewed. The genus is represented in the Mediterranean Sea by eleven species, of which seven are here described as new, all included conservatively in the subgenus Mitrolumna Bucquoy, Dautzenberg & Dollfus, 1883: Mitromorpha (Mitrolumna) columbellaria (Scacchi, 1836), Mitromorpha (Mitrolumna) olivoidea (Cantraine, 1835), Mitromorpha (Mitrolumna) karpathoensis (Nordsieck, 1969), Mitromorpha (Mitrolumna) wilhelminae (van Aartsen, Menkhorst & Gittenberger, 1984), Mitromorpha (Mitrolumna) alyssae n. sp., Mitromorpha (Mitrolumna) bogii n. sp., Mitromorpha (Mitrolumna) cossyrae n. sp., Mitromorpha (Mitrolumna) nofronii n. sp., Mitromorpha (Mitrolumna) mariottinii n. sp., Mitromorpha (Mitrolumna) mifsudi n. sp., and Mitromorpha (Mitrolumna) tricolorata n. sp. Neotypes are designated for: Mitra columbellaria Scacchi, 1836, [currently Mitromorpha columbellaria (Scacchi, 1836) comb. nov.], and Mitrolumna algeriana Pallary, 1900 ex Monterosato ms. [currently Mitromorpha algeriana (Pallary, 1900) comb. nov.] considered as a synonym of Mitromorpha columbellaria (Scacchi, 1836). The latter is the oldest available name for the most common and widespread Mediterranean species of Mitromorpha. A lectotype is selected for Mitra leontocroma Brusina, 1866 [currently Mitromorpha leontocroma (Brusina, 1866) comb. nov.], previously considered as a junior synonym of Mitromorpha olivoidea (Cantraine, 1835) but here considered as a junior synonym of Mitromorpha columbellaria (Scacchi, 1836). Mitromorpha melitensis (Mifsud, 1993) is a synonym of Mitromorpha olivoidea (Cantraine, 1835). Mitromorpha mediterranea Mifsud, 2001 is a synonym of Mitromorpha columbellaria (Scacchi, 1836).

Coralliophilid gastropods include a large number of described species, grouped in at least seven to 10 ‘genera’ according to their shell morphology. They are considered closely related to Muricidae and ranked as a family on its own or as a subfamily of muricids. Their phylogenetic position and relationships are still not defined. The little anatomical work so far done on this group seems to indicate a relatively high level of homogeneity, at least in the alimentary system. There is a need for an independent phylogenetic framework to understand their position and relationship within the muricoideans, and their internal systematics and phylogeny. We have addressed this problem by means of parsimony analysis of 609 aligned positions of the sequences coding for the 12S rDNA. Four coralliophilid sequences representing the same number of commonly recognized lineages (Babelomurex, Latiaxis, Coralliophila, Galeropsis � Quoyula) were analysed, along with three sequences of muricoid genera (Stramonita, Phyllonotus, Nucella) representing as many subfamilies of Muricidae, plus the sequence of the buccinoidean Fasciolaria as outgroup. Maximum parsimony and neighbour-joining analysis of the dataset, with increasing weighing of transversions versus transitions, yielded similar topologies. Two major outcomes resulted from the analyses: first, the coralliophilid sequences included herein are always monophyletic, with very high bootstrap support in all analyses. This is in agreement with the few anatomical data gathered so far that suggest coralliophilids are relatively homogeneous. Secondly, the sister-group of the coralliophilids among the analysed sequences is represented by Stramonita, with high bootstrap support in all analyses. This is in a good agreement with previous molecular analyses and with the morphological evidence that Rapaninae are the closest sister group of coralliophilids. According to the present results, the rank of the coralliophilids should be the same as Rapaninae, therefore a subfamilial status (Coralliophilinae) seems reasonable.

Background Hematophagy arose independently multiple times during metazoan evolution, with several lineages of vampire animals particularly diversified in invertebrates. However, the biochemistry of hematophagy has been studied in a few species of direct medical interest and is still underdeveloped in most invertebrates, as in general is the study of venom toxins. In cone snails, leeches, arthropods and snakes, the strong target specificity of venom toxins uniquely aligns them to industrial and academic pursuits (pharmacological applications, pest control etc.) and provides a biochemical tool for studying biological activities including cell signalling and immunological response. Neogastropod snails (cones, oyster drills etc.) are carnivorous and include active predators, scavengers, grazers on sessile invertebrates and hematophagous parasites; most of them use venoms to efficiently feed. It has been hypothesized that trophic innovations were the main drivers of rapid radiation of Neogastropoda in the late Cretaceous. We present here the first molecular characterization of the alimentary secretion of a non-conoidean neogastropod, Colubraria reticulata. Colubrariids successfully feed on the blood of fishes, throughout the secretion into the host of a complex mixture of anaesthetics and anticoagulants. We used a NGS RNA-Seq approach, integrated with differential expression analyses and custom searches for putative secreted feeding-related proteins, to describe in detail the salivary and mid-oesophageal transcriptomes of this Mediterranean vampire snail, with functional and evolutionary insights on major families of bioactive molecules. Results A remarkably low level of overlap was observed between the gene expression in the two target tissues, which also contained a high percentage of putatively secreted proteins when compared to the whole body. At least 12 families of feeding-related proteins were identified, including: 1) anaesthetics, such as ShK Toxin-containing proteins and turripeptides (ion-channel blockers), Cysteine-rich secretory proteins (CRISPs), Adenosine Deaminase (ADA); 2) inhibitors of primary haemostasis, such as novel vWFA domain-containing proteins, the Ectonucleotide pyrophosphatase/phosphodiesterase family member 5 (ENPP5) and the wasp Antigen-5; 3) anticoagulants, such as TFPI-like multiple Kunitz-type protease inhibitors, Peptidases S1 (PS1), CAP/ShKT domain-containing proteins, Astacin metalloproteases and Astacin/ShKT domain-containing proteins; 4) additional proteins, such the Angiotensin-Converting Enzyme (ACE: vasopressive) and the cytolytic Porins. Conclusions Colubraria feeding physiology seems to involve inhibitors of both primary and secondary haemostasis, anaesthetics, a vasoconstrictive enzyme to reduce feeding time and tissue-degrading proteins such as Porins and Astacins. The complexity of Colubraria venomous cocktail and the divergence from the arsenal of the few neogastropods studied to date (mostly conoideans) suggest that biochemical diversification of neogastropods might be largely underestimated and worth of extensive investigation. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1648-4) contains supplementary material, which is available to authorized users.