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The Mediterranean mangeliid species commonly ascribed to the genus Mangelia Risso, 1826 are here reviewed with the description of three new species: Mangelia algarvensis Spada n. sp., M. striolatoides Sabelli & Spada n. sp. and Mangelia tenuisculpta Spada n. sp. One new genus, Pseudomangelia n. gen. Sabelli & Spada (type species Pleurotoma vauquelini Payraudeau, 1827) is described and the genera Lyromangelia Monterosato, 1917, Pyrgocythara Woodring, 1928, Smithiella Monterosato, 1880 and Villersiella Monterosato, 1890 are resurrected on the basis of different morphology of the shell, of the living animal and of the radula.

A tentative list of shelled gastropods cited from the Red Sea wich can presumabily be found in the Red Sea is proposed. I refer mainly to bibliographical sources but also on the large collection of the Museum of Zoology of the University of Bologna. When possible my attempt was to indicate the location of types, their online figures, the findings, habitat and all biological characteristics I can found about each species. The list comprises 2797 names of species of which about 1183 still deserve taxonomic work to ascertain their validity or are doubtful and probably most of them, about 50% should be excluded from the true Red Sea fauna.

We revise the type specimens of 132 nominal species of worldwide Triphoridae stored in the Natural History Museum of the United Kingdom (NHMUK), London. We provide the species name in its original combination, followed by bibliographic details of the original description, the location of the known type material, the original description (and its translation when in Latin), a diagnosis and curatorial or nomenclatural notes. We illustrated most specimens in the type series in colour and with SEM imaging and we have added the original figure whenever possible. The specimens ofTriphorisalveolatus,T.granulatus,T.suturalisandT.verrucosus, all A. Adams & Reeve, 1850,T.pfeifferiCrosse & Fischer, 1865 andT.cucullatusde Folin, 1867, previously considered type material, are not considered here belonging to the type series. Adams & Reeve’s taxa should be considerednomina dubia. The nameTriphorainsularumis a manuscript name by H.E.J. Biggs who deposited “types” in the NHMUK but refrained from introducing the name due to the lack of apex of the studied material. We selected lectotypes for six species (T.concorsHinds, 1843,T.maxillarisHinds, 1843,T.fuscomaculataE.A. Smith, 1904,T.shepstonensisE.A. Smith, 1906,T.eupunctataG.B. Sowerby III, 1907, andT.rufulaWatson, 1886) to stabilize the nomenclature. Finally, we illustrate original specimens (although not types) of three species described by Turton, whose type material is lost.

Species are fundamental units in evolutionary biology. However, defining them in taxonomically problematic groups requires integration of independent sources of information in order to develop robust hypotheses for taxonomic classification. Here, we propose an integrative framework for species delimitation in the Mediterranean species of the genus Cerithium (Caenogastropoda: Cerithiidae), whose shells show a wide variety of forms resulting in problematic morphological identification at the species level. Combined sequence data of two mitochondrial genes (COIþ12S) for 55 individuals from the central Mediterranean Sea were used to test the species status of six identified morphotypes. Phylogenetic analyses, as well as DNA-based methods of species delimitation (automatic barcode gap discovery, species delimitation plugin and genealogical sorting index), support the species status of three morphotypes (C. vulgatum ¼ MOTU-A, C. alucastrum ¼ MOTU-B and C. protractum ¼ MOTU-C), sometimes considered as ecotypes. Molecular operational taxonomic unit (MOTU)-D includes large individuals morphologically assigned to C. vulgatum (from Brindisi and Oristano) and C. repandum (from Tunisia), but all probably represent C. repandum which, if valid, would then not be endemic to its type locality in the Gulf of Gabe` s. All individuals identified as C. lividulum grouped in MOTU-E, except those from Tunisia which cluster in MOTU-F with some C. renovatum. Cerithium renovatum from Crete forms an endemic group (MOTU-G), suggesting a possible cryptic species. Our results show only partial concordance between traditional morphology and sequence data, indicating that the former is not always sufficient for recognizing species level taxa within Mediterranean Cerithium, although protoconch morphology is a key feature for distinguishing between species with superficially similar teleoconchs. Further analyses based on more comprehensive geographic sampling and more mitochondrial markers, and including a number of nuclear loci, are needed to clarify Mediterranean Cerithium diversity more fully.

Distribution shifts of intertidal species have been thoroughly described for several organisms on the Atlantic coasts of Europe, but comparatively less work has been conducted in the Mediterranean Sea. However, such semi-enclosed basins react faster to global change. The periwinkle Echinolittorina punctata is a littorinid gastropod which has shown a remarkable range expansion during the last few decades. Moreover, its unambiguous taxonomy, accessible habitat and ease of identification qualify it as an ideal descriptor of biotic changes in the Mediterranean Sea. We investigated genetic differentiation among 17 Mediterranean and Atlantic populations covering its current distributional range, using the mitochondrial cox1 marker to test the hypothesis that it experienced a significant range expansion triggered by sea warming after the Last Glacial Maximum (LGM). This would confirm its suitability as descriptor of climatic fluctuations. E. punctata has a weak population structure along its distributional range, with greater haplotype diversity in the western African populations than in the Mediterranean Sea, suggesting a recent population expansion following a bottleneck event. Such range expansion is dated ca. 15,000 years BP, and is, thus, related to the end of LGM. E. punctata planktotrophic development lasts 3–4 weeks, likely triggering the weak population structure and enhanced ability to track environmental change.

Size-frequency distributions can support reliable inferences concerning population dynamics of brachiopods, but only a few data are available so far. In this study, length and width frequency distributions of dead specimens of the Recent brachiopods Joania cordata and Argyrotheca cuneata from the Marine Protected Area ‘Secche di Tor Paterno’, Central Tyrrhenian Sea, Italy (41°35′ N, 12°20′ E), are reported in order to add new data about size-frequency distributions of brachiopods. The studied specimens came from death assemblages in the coralligenous substrate, in the Posidonia oceanica meadows, and in the sand channels. The observed patterns vary from left-skewed (J. cordata) to right-skewed (A. cuneata), indicating respectively a low and high mortality of smaller individuals. Significant differences between the coralligenous substrate and the P. oceanica meadow were observed for both species, revealing a variation among different habitats. All length and width distributions are clearly polymodal, but the biological meaning of the peaks is difficult to interpret, as the two species seem to have a 2-year life span. A biometric analysis of shell sizes revealed that length and width are the most variable parameters during the growth of the animal.

Although molluscs feature prominently in the semi-popular and academic literature on marine biodiversity, field surveys largely ignore the small and rare species that form the majority of marine molluscan diversity. As a result of a massive effort to sample the benthic molluscs of a complex tropical coastal environment, 23,238 gastropod specimens representing 259 species of Triphoridae—a family with most adult species ranging from 2 to 10 mm—were obtained from a 45,000 hectares study area off the island of Espiritu Santo, Vanuatu. Most species are represented by fewer than 20 specimens and, despite the intensity of the sampling effort, 13% of the species are unique singletons. Spatial heterogeneity was high: out of 416 sampling events, 187 contained triphorids, and 42% of the species occurred at fewer than 5 stations. Most species were small (68% below 5 mm) or very small (22% below 3 mm). A faunal turnover was documented at around 10 m, and another at around 60 m, at the onset of the ‘‘twilight zone’’ that is particularly difficult to sample. On the order of 70% of the species are probably new to science. When dealing with taxonomically difficult groups a morphospecies segregation approach is operationally appropriate to detect patterns of richness, rarity and spatial turn-over. Very few, if any, conservation surveys have the human and funding resources to carry out baseline surveys of the intensity that generated the results presented here. However, as species numbers are often used to promote the conservation interest of a reef, a bay or a stretch of coast, it is essential to know how the numbers were generated: absolute numbers of species are meaningless unless sampling effort and techniques, area surveyed, and size classes targeted are described. This is very rarely the case, even in the academic literature.

SUMMARY: This work represents an attempt to resolve the confused and contradictory taxonomy of Mediterranean chitons of the genus Acanthochitona by analysing morphological (SEM observations of aesthetes, radula and girdle) and molecular data (COI, 12S, ITS1). Both analyses support the validity of the three species, Acanthochitona fascicularis, A. crinita and A. oblonga, the latter two of which were previously considered as synonymous.

Anadara demiri (Piani, 1981) is an alien species in the Mediterranean Sea extending its range from Turkey westernly to the Adriatic Sea, where it is locally abundant. The species was first identified as Arca amygdalum Philippi, 1847 in the 1970s. The locus typicus of A. amygdalum is China. This first identification has never been discussed and the species has been thought to be of Indo-Pacific origin to date. However, in the Indo-Pacific province no Anadara shows any similarity with A. demiri. Morphological and molecular data suggest A. demiri is closely related to Anadara transversa (Say, 1822), a common species of the eastern coasts of North America. Anadara demiri is hence considered a junior synonym of A. transversa and the origin of this immigration has to be searched in the southern range of this species, maybe the Gulf of Mexico coasts of Florida.

Predator holes in empty shells of Joania cordata and Argyrotheca cuneata (Brachiopoda: Megathyrididae) collected in the marine protected area ‘‘Secche di Tor Paterno’’, central Tyrrhenian Sea, Italy (41350N– 12200E, at depths of 20–28 m), were analyzed. Predation intensity was low but appreciable, with the more common species J. cordata preyed on more frequently (6.7 %) than A. cuneata (3.8 %). Three main types of holes were recognized: (1) cylindrical drill holes with a circular outline, (2) larger irregular holes with a jagged outline, and (3) small holes at the bottom of depressions in the shell. They were probably produced by muricid gastropods, crabs, and Foraminifera, respectively. The large, irregular holes were the most common type in both brachiopod species. Evidence for predator selectivity with respect to which valve, the position of the hole on the valve, and the size of the brachiopod with respect to those available was assessed. The ventral valve, the postero-medial portions of both valves, and larger (J. cordata) or medium-sized (A. cuneata) shells were more frequently holed.

Rajidae (colloquially known as skates and rays) experienced multiple and parallel adaptive radiations allowing high species diversity and great differences of species composition between regional faunas. Nevertheless, they show considerable conservation of bio-ecological, morphological and reproductive traits. The evolutionary history and dispersal of North-east Atlantic and Mediterranean rajid fauna were investigated throughout the sequence analysis of the control region and 16S rDNA mitochondrial genes. Molecular estimates of divergence times indicated recent origin and rapid dispersal of the present species. Compared with the ancient origin of the family (Late Cretaceous), the present species diversity arose in a relatively narrow time-window (12 Myr) from Middle Miocene to Early Pleistocene, likely by speciation processes related to dramatic geological and climatic events in the Mediterranean. Nucleotide substitution rates and phylogenetic relationships indicated Mediterranean endemic skates derived from sister species with wider distribution during Late Pliocene–Pleistocene. Skate phylogeny and systematics obtained using mitochondrial gene variation were largely consistent with those based on morpho-anatomical data.

The Northeast Atlantic and Mediterranean skates (Rajidae) showed remarkable species diversity but with high morphological and ecological conservatism. Since skates are particularly vulnerable to the bottom trawl fishery, species-specific demographic surveys as well as studies defining life history and evolutionary traits are important in prioritising conservation programs. However, the identification of juveniles and adults of some species may be difficult using referenced guidelines and identification keys. Therefore, we attempt to develop markers for species identification through the parallel analysis of a 16S rDNA gene sequence and of several morphological characters on 135 individuals collected by trawl surveys in the Adriatic Sea and putatively assigned to six taxa. Species-specific haplotypes were defined for Raja miraletus, Raja montagui, Dipturus oxyrinchus, since a solid accordance between species boundaries and well-differentiated haplotypes was observed. Comparative analysis of 16S rDNA sequences allowed the identification of three juvenile specimens of Leucoraja circularis, a species that rarely occurs in the Adriatic Sea. On the contrary, morphological traits and haplotype distribution were largely discordant in Raja asterias and R. clavata. While all putative R. clavata individuals showed a unique haplotype (H-CLA), only 8 of 30 putative R. asterias individuals possessed a second weakly divergent haplotype (H-AST). The remaining 22 R. asterias carried the H-CLA. The multivariate analyses of morphometric and meristic characters in putative R. clavata and R. asterias revealed the clustering of individuals regardless of haplotypes. However, a bimodal distribution of R. asterias and R. clavata samples would suggest that two separated taxa might exist, both sharing the two 16S rDNA haplotypes. The haplotype distribution appeared to be significantly correlated only to the standardised disc length/total length (DL/TL) variation. Three alternative explanations may support this scenario: (i) an incomplete lineage sorting process in two morphologically yet distinct taxa; (ii) a recent hybridisation between the two taxa; (iii) the two taxa are morphologically plastic species and all considered morphological characters may be misleading in discriminating between them at all maturity stages, except for the DL/TL. However, further analyses on larger data sets and using molecular key markers (i.e. nuclear genes) will be needed to definitely resolve the status of these taxa. Molecular relationships among rajid taxa are largely consistent with systematics based on internal and external anatomical features. This multidisciplinary study contributed to defining the pattern of species diversity and abundance of rajids in the Adriatic Sea.

The importance of natural history museums is often underappreciated, but they provide society with a number of services. Among these, they are a fundamental tool for assessing extinction rates and range contractions, or the only way to access species extinct in historical times. In this perspective, we describe here the collection of Unionida of the Museo di Zoologia dell'Università di Bologna, containing one extinct (Epioblasma haysiana) and nine threatened species, plus another 47 species. The collection was built in the mid-19th century and potentially provides baseline information for specialists. In the fragmented natural history museum system of Italy, this might be just the tip of the iceberg of a significant and important amount of material collected in the 19th and early-20th century.

Epitonium (Asperiscala ?) oliverioi new species (Gastropoda, Ptenoglossa, Epitoniidae) characterized by two different teleoconch microsculptures is described from the Tulear region (SW Madagascar). A brief comparison of its spawn and radular morphology with those known of other epitoniids is also given in order to provide further characters for specific and supraspecific classification.

The molluscan assemblages inhabiting the leaf and rhizome layers of Posidonia oceanica were studied in a deep water (–24/26 m) settlement of a highly heterogeneous substratum on an off-shore reef in the central Tyrrhenian Sea. This is one of the few works dealing with the rhizome layer and with Posidonia oceanica that has settled on hard substrata. The leaf assemblage only had a few species, less than other assemblages at a comparable depth in the same basin. This poorness may be due to the depth, but it may also be due to the high fragmentation of the meadow. However, the high percentage of carnivores is consistent with previous observations in deep water meadows. The rhizome assemblage is highly diverse both in terms of species and feeding guilds, which could be explained by the higher affinity for low light conditions of most molluscs and the greater habitat heterogeneity. The marked differences in the two taxocoenoses and the high diversification of the rhizome assemblage evidence that they should be included in studies on the potential diversity of Posidonia oceanica meadows. Failure to consider this layer seriously affects any evaluation of the biodiversity of this habitat, which is of great conservation interest.

The agreement between the death (DA) and the living (LA) molluscs assemblages is analyzed in an infralittoral off-shore reef in the Central Tyrrhenian Sea (“Secche di Tor Paterno” Marine Protected Area) with extensive coralligenous and Posidonia oceanica biocoenoses. These biocoenoses host a highly diverse assemblage of small sized species. The work has a high species resolution and takes into consideration the richest but also more taxonomically difficult size class (1–6 mm). DAs contain allochthonous species which mainly live in deeper soft substrates but also contain species which were under-represented in the LA samples because they are endolithic or cemented to hard substrates, although such species are numerically rare. Multivariate analysis shows there are significant differences between living and death assemblages within habitats, but also that DAs are able to discriminate the two types of habitat. Fidelity of species richness and evenness is better in the coralligenous biocoenosis rather than in the P. oceanica meadow. This may be due to the reduced transport of shells out of the rhizome layer due to its reduced hydrodynamism due to the effect of the canopy. The good fidelity in the coralligenous biocoenosis suggests that the situation is close to complete ergodic mixing that draws individuals that coexisted or potentially coexisted in the same habitat into the DA. The lower fidelity in the P. oceanica meadow suggests incomplete ergodic mixing which can occur when within-habitat spatial mixing does not result in homogenization of dead skeletal material because transportation is non-uniform. Marked differences in species abundance between the LA and the DA are observed in both habitats and the result is consistent with previous works in similar habitats. Among the factors influencing fidelity, we hypothesize that trophic guild and life span of species may influence species abundance because carnivores and scavengers are more abundant in the living assemblage while microalgae herbivores are more abundant in the death assemblage. This difference in the fidelity of guild abundance may be connected to the different life span of species because many herbivores have short life span while carnivores and scavengers have long life span, although this issue needs to be further tested. On the contrary, temporal changes in community composition and individual preservation rate are not considered to influence fidelity significantly. The study suggests low bottom transport of dead shells in these habitats. This work opens good prospects for biodiversity assessments on the basis of DAs because it allows reduced diving and field time and better faunistic description due to time-averaging. However, dead specimens tend to lose important diagnostic characters and may require more skilled personnel for sorting and identification.

The chitons studied here are all from the coral reefs in the Tuléar area, SW Madagascar. This second note on Tuléar chitons benefits of the availability of well preserved complete specimens whereas the previous one (DELL’ANGELO et al. 2004) was mainly based on single valves. A small collection of living-collected Polyplacophora from shallow coral reef habitats in Tulèar permits to update the chiton fauna from Madagascar. The material was collected in the 1960s/70s (main collector JEAN FRANCOIS BRUNEL in 1971) by people then working at Station Marine d’Endoume, Marseille, and consists of seven species: Callistochiton rotondus LELOUP 1981, Chiton kaasi (LELOUP 1981), Lucilina tilbrooki MILNE 1958, Acanthochitona penicillata (DESHAYES 1863), Acanthochitona limbata KAAS 1986, Choneplax indica ODHNER 1919, and Cryptoplax sykesi THIELE 1909. Before, Lucilina tilbrooki was formerly only known from Heron Island, Australia. The finding of Callistochiton rotondus is noteworthy because is a very elusive species previously only known from the holotype.

Taviani, M., Sabelli, B. & Candini, F. 1990 04 15: A fossil Cenozoic monoplacophoran. Lethaia, Vol. 23, pp. 213–216. Oslo. ISSN 0024–1164. A few shells of Micropilina (Mollusca, Monoplacophora) have been found in middle Pleistocene (Sicilian) epibathyal clays at Archi (Reggio Calabria, southern Italy). The species appears conchologically indistinguishable from the Recent Atlantic taxon Micropilina minuta Waren, 1989. This finding represents the first record of a Cenozoic fossil monoplacophoran.

Diencephalic habenular nuclei of several species of Chondrohycthes and Ostehycthes fishes were investigated in order to ascertain their asymmetry. Raja asterias, Squalus acanthias, Mustels mustelus, Scyliorhinus canicula and Scyllium stellare show the left habenula larger than the right, as occurs in the elasmobranchs till now investigated. Among the six species of teleostean fishes we studied, the habenulae of Liza aurata, Anguilla anguilla and Trisopterus minutus are symmetrical, while in Lepidorhombus boscii, Platichthys flesus and Solea vulgaris the habenulae are slightly asymmetrical. This finding might suggest a relation, to be better investigated, among bentic life and habenular asymmetry in teleostean.

Reproductive biology of Nassarius reticulatus is well known, but informations about Nassarius mutabilis are scarce; we have so undertaken a macroscopical and histological study to clear the reproductive biology of this species.

Deltaic populations of Conopeum seurati from diverse environmental settings have variable phenotypes related to strong competitive regimes and to dissolved oxygen minima. Under extremely stressful conditions, the poorly canalized phenotype of C. seurati displays new additional features such as kleistozooids (kleistos= closed) and chaotic celleporoid layers. Kleistozooids are clearly distinguishable polymorphs characterized by the presence of a compact, imperforate frontal membrane and by a strongly reduced lumen of the “opesium”. They commonly aggregate in clusters of regularly-arranged individuals that store a large quantity of proteic material. The inferred function of these cell-like structures is to supply nutrients for basic colony activities. Celleporoid layers are, possibly, a developmental relaxation of the colony of C. seurati for a more efficient use of space in competitive interactions. Both celleporoid layers and kleistozooids reveal the magnitude of intracolony variability of a widespread opportunistic bryozoan species.

The cladoceran Daphnia middendorffiana is an arctic species able to produce winter eggs which develop parthenogenetically. The cytological study of the maturation of summer and winter eggs of an italian population of this species has shown that both types of eggs undergo only one maturation division of equational type with the expulsion of only one diploid polar body, the same maturation process as had been found in the pseudosexual eggs of a race of Daphnia pulex (Schrader, 1925).—The chromosomes behaviour during the maturation of summer and winter eggs of D. middendorffiana has been compared with that of a population of D. pulex which shows a normal heterogonic cycle.

The molluscan assemblages inhabiting the leaf and rhizome layers of Posidonia oceanica were studied in a deep water (–24/26 m) settlement of a highly heterogeneous substratum on an off-shore reef in the central Tyrrhenian Sea. This is one of the few works dealing with the rhizome layer and with Posidonia oceanica that has settled on hard substrata. The leaf assemblage only had a few species, less than other assemblages at a comparable depth in the same basin. This poorness may be due to the depth, but it may also be due to the high fragmentation of the meadow. However, the high percentage of carnivores is consistent with previous observations in deep water meadows. The rhizome assemblage is highly diverse both in terms of species and feeding guilds, which could be explained by the higher affinity for low light conditions of most molluscs and the greater habitat heterogeneity. The marked differences in the two taxocoenoses and the high diversification of the rhizome assemblage evidence that they should be included in studies on the potential diversity of Posidonia oceanica meadows. Failure to consider this layer seriously affects any evaluation of the biodiversity of this habitat, which is of great conservation interest.