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Micro-computed tomography (micro-CT) is a high-resolution 3D-imaging technique which is now increasingly applied in biological studies focusing on taxonomy and functional morphology. The creation of virtual representations of specimens can increase availability of otherwise underexploited and inaccessible samples. The 3D model dataset can be also further processed through volume rendering and morphometric analysis. The success of micro-CT as a visualisation technique depends on several methodological manipulations, including the use of contrast enhancing staining agents, filters, scanning mediums, containers, exposure time and frame averaging. The aim of this study was to standardise a series of micro-CT scanning and 3D analysis protocols for a marine gastropod species, Hexaplex trunculus. The analytical protocols have followed all the developmental stages of this gastropod, from egg capsules and embryos to juveniles and adults.

The geologic record of the shallow-marine gastropod genusPseudoperissolaxClark, 1918 is documented in detail for the first time in a region of the northeast Pacific extending from southwestern Washington to northern Baja California, Mexico. This genus, which has been erroneously equated with thenomen dubium PerrisolaxGabb, 1861, comprises a very small group of species whose supra-generic ranking has been inconsistent.Pseudoperissolaxis placed here in family Muricidae Rafinesque, 1815 and subfamily Muricinae Rafinesque, 1815 based on the presence of varices, a club-shaped last whorl with noded carinae, and a long siphonal canal. The genus is represented in the northeast Pacific by the late PaleocenePseudoperissolax tricarnatus(Weaver, 1905) and the late Paleocene to late EocenePseudoperissolax blakei(Conrad, 1855).Pseudoperissolaxwas a warm-water gastropod that most likely originated during the Late Cretaceous (Maastrichtian) in Madagascar and also questionably spread during this time to southern New Zealand. Its certain geologic range is early Paleocene to earliest Oligocene, with occurrences in western Kamchatka, southern Japan, southwestern Washington, southwestern Oregon, southern California, northern Baja California, Mexico, southern Alabama, and Nuevo León, northeastern Mexico. WhetherPseudoperissolaxmigrated into the northeast Pacific from Kamchatka or from Alabama and Mexico cannot be determined with certainty. The decline and eventual extinction of the genus coincided with the global-cooling event at the end of the Eocene.

The current investigation provides the first histomorphological description of the female pallial gonoduct in the muricid mollusc Dicathais orbita, and of sperm passage in the subfamily Rapaninae. Gonoduct anatomy, musculature, and sperm distribution were documented over the annual reproductive cycle to confirm the site of fertilization in members of the Muricidae, provide evidence for sperm storage, and allow subfamilial comparisons in reproductive anatomy and strategies. This approach revealed morphological plasticity of the ingesting gland in D. orbita, which has implications for the use of gonoduct character traits in taxonomic studies of the Muricidae. Other features of subfamilial diagnostic interest, including the ventral channel and both albumen and capsule glands, are highlighted to show common character traits between the Rapaninae, Ocenebrinae, and Muricinae. Conversely, distinct differences in posterior capsule and pedal gland morphology may aid subfamilial classification of Rapaninae species in future revisions of the Muricidae. Histomorphology coupled with sperm distribution revealed the passage of sperm and identified the dorsal albumen gland as the site of fertilization. Temporally replicated sampling indicated the potential for sperm storage for ≤10 months within the seminal receptacles in D. orbita. Sperm ingestion provides a possible mechanism for sexual selection, suggesting further investigation into sperm storage is warranted in the Muricidae.

The purple dye murex, Bolinus brandaris (Linnaeus, 1758), is a muricid gastropod common throughout the Mediterranean and along the Moroccan and Portuguese Atlantic coasts. In the present study, we confirmed the diploid chromosome number of 2n = 70 for this species, and established for the first time the karyotype, which comprised 12 metacentric, 15 submetacentric and eight subtelocentric chromosome pairs. To facilitate cytotaxonomic comparisons, we carried out a comparative karyological analysis through multidimensional scaling between B. brandaris and three other 2n = 70 muricid species (Hexaplex trunculus, Ocenebra erinaceus, and Stramonita haemastoma) for which chromosomal measurements have been previously published. The interpretation of the ideograms and the statistical analysis highlighted the closest similarity of B. brandaris and H. trunculus compared to S. haemastoma and O. erinaceus. Indeed, B. brandaris and H. trunculus showed the smallest dissimilarities both for relative length and arm ratio, with O. erinaceus presenting intermediate values, whereas the highest dissimilarities were found between H. trunculus and S. haemastoma for both data. The karyotypes of B. brandaris and H. trunculus (subfamily Muricinae) presented the highest proportions of metacentric chromosomes compared to the other two muricids analysed, suggesting that those karyotypes could be considered primitive within the 2n = 70 Muricidae studied so far. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 185–193.

The neogastropod family Muricidae includes a diverse set of radular bauplane, including a beaked, three-dimensional form, a flattened-pentacusped form, and a third “dagger” type in which the central rachidian cusp is massive and elongate. Examination of the radular ontogenies of representatives of five muricid subfamilies reveals that several species undergo changes in radular form during ontogeny on a scale comparable to the evolutionary differences between higher taxa. The species Concholepas concholepas (Bruguiere, 1789) (Rapaninae) and Trophon geversianus (Pallas, 1774) (Trophoninae) begin ontogeny with a three-dimensional rachidian characteristic of the Ocenebrinae or Muricopsinae but end with the dagger rachidian typical of their respective subfamilies. Young individuals of Vitularia salebrosa (King and Broderip, 1832) (Muricopsinae?) also have a three-dimensional rachidian but shift to a double-dagger morphology by adulthood. Chicoreus (Phyllonotus) pomum (Gmelin, 1791) (Muricinae) has a typical fl...

Summary Tyrian purple is a well-known colourant that can be obtained from the hypobranchial glands of muricids. Here we investigate the presence of purple and related pigments in the hypobranchial glands, reproductive glands and egg capsules of three Rapaninae, three Ocenebrinae and one Muricinae species. Observations on the dissected specimens revealed the presence of purple pigmentation in the hypobranchial glands of all species. All of the Rapaninae and the Muricinae, but only some species of Ocenebrinae, appear to transfer the pigment precursors to their egg capsules. This provides evidence that the precursors of Tyrian purple are not produced for the sole purpose of protecting the egg masses as has been previously suggested. In all the subfamilies, the hypobranchial and reproductive (capsule and prostate) glands lie adjacent to one another. Colour changes in the reproductive glands, indicating the presence of dye precursors, were observed in two species of Rapaninae. In Dicathais orbita, colour chang...

We report DNA sequence variation in 861 bp of the mitochondrial cytochromeb gene from 10 species of the dasyurid marsupial subfamily Phascogalinae (including the New Guinean genusMurexia) and an outgroup planigale (Planigale ingrami). Phylogenetic analyses of these sequences indicate that (1) the subfamily consists of three major clades corresponding to (a)Phascogale, (b) AustralianAntechinus, and (c) New Guinean “Antechinus” andMurexia; (2) “Antechinus” habbema constitutes the earliest branch of the New Guinean clade; and (3); “Antechinus” melanurus and “A.” naso are sister species within the New Guinean clade. Among Australian antechnuses,A. stuartii andA. swainsonii are more closely related to each other than either is toA. flavipes, a result that is seemingly at odds with all previous systematic studies. Although resolution is limited, it appears thatAntechnius andMurexia species form a clade to the exclusion ofPhascogale. This relationship suggests that male semelparity is not a strong synapomorphy for Australian antechinuses and phascogales, despite its apparent physiological similarity in the two groups.

The extreme south of Madagascar is noted for the endemism of its marine biota, notably molluscs. Six new species of Muricidae Rafinesque, 1815 are described in the present paper; three in the subfamily Muricinae Rafinesque, 1815: Chicoreus (Triplex) kantori n. sp., Naquetia manwaii n. sp. and Dermomurex (Dermomurex) charlesi n. sp.; two in the subfamily Muricopsinae Radwin & D'Attilio, 1971: Favartia (Favartia) tantelyi n. sp. and Favartia (Pygmaepterys) fournierae n. sp.; and one in the subfamily Rapaninae Gray, 1853: Semiricinula bozzettii n. sp. Similar species from Madagascar and from other regions are compared and illustrated. The radula of Naquetia manwaii n. sp. and of Semiricinula bozzettii n. sp. are illustrated.

Archer provided the most recent and comprehensive suprageneric classification of dasyurid marsupials. Five extant subfamilies, two with constituent tribes, were recognized on the basis of morphological, serological, and allozyme data. Phylogenetic relationships among these groups, however, were totally unresolved. Subsequent molecular studies suggested that the endemic New Guinean subfamilies Muricinae and Phascolosoricinae are parts of larger Australian clades. Our objective in this study was to test the monophyly of Archer's seven groups and estimate relationships among them using DNA sequences from the mitochondrial cytochromeb (cyt-b) gene. We report 657 bp ofcyt-b from 32 dasyuroid species. Phylogenetic analysis of these data leads to the following conclusions: (1) muricines form a clade within Phascogalinae that includes endemic New GuineanAntechinus species; (2) the two genera of Phascolosoricinae are part of a more inclusive Dasyurinae; (3) Sminthopsinae is monophyletic, but the tribes Sminthopsini and Planigalini are not; and (4) the dasyurine tribes Dasyurini and Parantechini are probably not monophyletic. Relationships among Sminthopsinae, Dasyurinae (including phascolosoricines), and Phascogalinae (including muricines) remain unresolved.

The identification and phylogeny of muricids have been in a state of confusion for a long time due to the morphological convergence and plasticity. DNA-based identification and phylogeny methods often offer an analytically powerful addition or even an alternative. In this study, we employ a DNA barcoding method to identify 17 known and easily confused muricid species (120 individuals) from the whole China coast based on mitochondrial cytochrome c oxidase subunit I (COI) and 16S rRNA sequences, and nuclear ITS-1 and 28S rRNA sequences. The phylogeny of muricid subfamilies is also analysed based on all mitochondrial and nuclear sequences. The universal COI and 16S rRNA primers did not work broadly across the study group, necessitating the redesign of muricid specific COI and 16S rRNA primers in this paper. Our study demonstrates that COI gene is a suitable marker for barcoding muricids, which can distinguish all muricid species studied. Phylogenetic analysis of 16S rRNA, ITS-1 and 28S rRNA data also provide good support for the species resolution observed in COI data. The relationships of muricid subfamilies are resolved based on the separate and combined gene data that showed the monophyly of each the subfamilies Ergalataxinae, Rapaninae, Ocenebrinae and Muricinae, especially that Ergalataxinae did not fall within Rapaninae.

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.

Poirieria (Flexopteron) poppei is described from 2 specimens dredged off Balut Island, in the Philippmes. It is the second known Recent species of Flexopteron, and is compared with P. (F.) philippinensis (Shuto, 1969) and P. (F.) primanova Houart, 1985.