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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.

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 Gabès; 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 'large Tyrrhenian morphotype' (corresponding to the neotype, but not assayed herein) with the assayed 'small morphotype'. [ABSTRACT FROM AUTHOR]

The Ocenebrinae is a subfamily of marine predatory gastropods known as oyster and mussel drills. Their current phylogenetic framework is traditionally based on shell and radular characters, but a consensus on relationships among genera is still lacking. We investigated the molecular phylogeny of Ocenebrinae using 50 species and DNA data from one nuclear (28S) and two mitochondrial ( COI and 16S) genes, the largest data set so far assembled for this subfamily. We found support for the monophyly of the Ocenebrinae, and species were divided into four major lineages. Within groups, genera had similar geographic distributions, suggesting that except in a few cases, species diversification within clades occurred without range expansions. We discuss the phylogenetic distribution of a labral tooth and a sealed siphonal canal, two characteristic ocenebrine features. We also show that Ocinebrina species in the north-eastern Pacific are not monophyletic with north-eastern Atlantic and Mediterranean species, and that the Ocinebrina edwardsii species complex belongs to Ocenebra. [ABSTRACT FROM AUTHOR]

We used a molecular phylogenetic approach to investigate species delimitations and diversification in the mussel drills of the Ocinebrina edwardsii complex by means of a combination of nuclear (internal transcribed spacer 2, ITS2) and mitochondrial [cytochrome oxidase subunit I ( COI) and 16S] sequences. Our sample included 243 specimens ascribed to seven currently accepted species from 51 sites. Five of the samples were from either the type locality of a nominal species or a close nearby locality ( O. edwardsii from Corsica, O. carmelae and O. piantonii from the Kerkennah Islands, O. hispidula from the Gulf of Gabès and O. leukos from the Canary Islands), one from the inferred original locality ( O. ingloria from Venice Lagoon), and specimens assigned in the recent literature to O. nicolai. We used a combination of distance- and tree-based species delimitation methods to identify Molecular Operational Taxonomic Units ( MOTUs) to compare with the a priori species identifications. The consensus tree obtained by BEAST on the COI alignment allows the recognition of several distinct clades supported by the three species delimitation methods employed. The eight- MOTUs scenario, shared by the Automatic Barcode Gap Discovery ( ABGD) and Generalized Mixed Yule- Coalescent ( GMYC) methods, comprises the following major clades: clade A contains the south Tunisian species Ocinebrina piantonii Cecalupo, Buzzurro & Mariani from which the sympatric taxon O. carmelae Cecalupo, Buzzurro & Mariani (new synonym) cannot be separated; clades B and C bring together all populations from the Aegean Sea and some from the Ionian Sea, respectively; clade D groups, on the one hand, the south Tunisian samples morphologically assigned to O. hispidula Pallary and, on the other, Atlantic and Alboran Sea samples (including the Canarian taxon O. leukos Houart); clade E includes a sample from the type locality of O. edwardsii and several samples from the Tyrrhenian Sea; clades F and G correspond to a few samples from the Venice Lagoon and the Tyrrhenian Sea, respectively; clade H groups the bulk of samples from the Adriatic Sea, including samples from the Venice Lagoon morphologically identified as Ocinebrina ingloria ( Crosse), and some from the Ionian Sea. No final conclusions could be reached to reconcile the currently recognized morphological taxa with the clades suggested by the COI data. The geographical structure proposed by the mitochondrial markers is similar to that found in other marine invertebrates and partially corresponds to the species defined by shell characters. We propose here a framework for the revision of the Ocinebrina edwardsii species complex, suggesting a geographical pattern for the diversification of this group in the studied area. © 2013 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Three hundred years of study on the Mediterranean molluscan fauna led the scientific community to consider it as the best ever known. However, the rate at which new taxa are discovered and described every year is still remarkably high, even in key predators such as Muricidae Rafinesque, 1815. Within this family, the genus Ocenebra Gray, 1847 comprises species widely distributed in the northeastern Atlantic and the Mediterranean Sea that were already the target of a decadal nomenclatural, morphological, and molecular combined research. Notwithstanding, we hereby describe an additional ocenebrid endemism from the Mediterranean Sea, whose distribution appears to be restricted to a circalittoral submarine cave of the Messina Strait area (Italy). The new species Ocenebra vazzanai is compared with the recent Atlanto-Mediterranean congeneric taxa on the basis of the known type materials, and a table summarizing the main diagnostic features of the species is offered to facilitate future identifications. The high biodiversity highlighted in the genus Ocenebra reveals a wide adaptive radiation and suggests the necessity of further studies aiming to tackle biodiversity issues even in popular groups, such as molluscs, and in widely studied biogeographic areas, such as Italy, and the Mediterranean basin in general. [ABSTRACT FROM AUTHOR]