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A new capillariid nematode, Capillostrongyloides morae sp. n., is described from specimens collected from the stomach and intestine of the common mora, Mora moro, and the Mediterranean codling, Lepidion lepidion (both Gadiformes, Moridae), off the Mediterranean coasts of Spain. The new species shows similar morphological features as other congeneric species occurring in freshwater and marine fishes, but it differs in the length of the body and spicules, the size of the caudal bursa, and the presence of an elevated anterior vulvar lip. Capillostrongyloides morae sp. n. is the second species within the genus for which the presence of a stylet is reported, and the first one in which this structure along with the distribution of cephalic papillae and oral structures (e.g. lips and lobes) are clearly shown by using scanning electron microscopy.

There is some evidence that the presence of Tursiops truncatus in fishing areas represents a real economic threat to fishermen due the dolphin feeding on the entangled fish, damaging the nets and reducing the fish catch. We have carried out experiments to assess the efficiency of a pinger in decreasing the interaction between the dolphins and fishing nets, in a fishing area off the coast of southern Italy, where Tursiops truncatus is frequently observed to interact with bottom gill nets. Two identical monofilament bottom gill nets (900 m long), one equipped with pingers and the other without, were used to measure the effect of these pingers on the abundance of the catch and net damage. For each haul (58 in total), data on dolphin sightings near the nets, damage judged to have been done by dolphins, weight and species composition of the catch were collected. All damages to the nets were recorded at the end of each haul. Dolphins in the fishing area were sighted 11 times out of 29 fishing activities (38%). The net equipped with pingers contained 28% more fish (biomass) than the net without pingers (t test, P0.04) and was less damaged (-31%, t test, P0.01). To assess whether the efficacy of these pingers remain constant over long period, long-term experiments should be carried out.

Chloromyxum leydigi Mingazzini, 1890, the type species of Chloromyxum Mingazzini, 1890, is redescribed based on material found in the gall bladder of the cartilaginous fish Torpedo marmorata Risso collected from the Portuguese Atlantic coast and its sporogonic development is described. Plasmodia and mature spores were floating free in the bile. Plasmodia are polysporic and highly polymorphic in shape and organization. Mature spores are spherical to subspherical with a pointed anterior end, measuring 12.3 +/- 0.5 microm in length and 9.0 +/- 0.5 microm in width. The spore wall is composed of two asymmetric shell valves, each bearing 4-5 elevated surface ridges. A bundle of 40-50 tapering caudal filaments extends from the basal portion of the shell valves. Four pyriform equal-sized polar capsules, measuring about 5.3 x 3.2 microm, are observed at the same level in the anterior pole of the spores, each containing a polar filament coiled in 8-9 (rarely 10) turns. Spore morphology, tissue tropism, host species and sequences of the SSU rRNA gene supported species identification. Since its discovery, this species has been dubiously reported from several cartilaginous hosts, namely due to the poor description of its features.

:  Univariate and multivariate autoregressive integrated moving average (ARIMA) models were used to model and forecast the monthly pelagic production of fish species in the Mediterranean Sea during 1990–2005. Autocorrelation (AC) and partial autocorrelation (PAC) functions were estimated, which led to the identification and construction of seasonal ARIMA models, suitable in explaining the time series and forecasting the future catch per unit of effort (CPUE) values. Univariate and multivariate ARIMA models satisfactorily predicted the total pelagic fish production and the production of anchovy, sardine, and horse mackerel. The univariate ARIMA models demonstrated a good performance in terms of explained variability and predicting power. The current findings revealed a strong autoregressive character providing relatively high R2 and satisfactory forecasts that were close to the recorded CPUE values. The present results also indicated that the multivariate ARIMA outperformed the univariate ARIMA models in terms of fitting accuracy. The opposite was evidenced when testing the forecasting accuracy of the two methods, where the univariate ARIMA models overall performed better than the multivariate models. The observed seasonal pattern in the monthly production series was attributed to the intrinsic nature of the pelagic fishery. As anchovy, sardine, and horse mackerel represent main target species in the Mediterranean pelagic fishery, the findings of the present study provided direct support for the potential use of accurate forecasts in decision making and fisheries management in the Mediterranean Sea.

The gills of 63 specimens of the Atlantic bluefin tuna Thunnus thynnus (Osteichthyes: Scombridae) from three localities of the Mediterranean (Sardinian, Tyrrhenian and Levantine Seas) were examined for metazoan parasites. The parasite fauna of T. thynnus from the Sea of Sardinia included 11 species: five didymozoid trematodes, three capsalid and one hexostomid monogeneans, and one caligid and one pseudocycnid copepods. Four didymozoids were found in fish from the Levantine Sea and only one didymozoid was recorded in fish from the Tyrrhenian Sea. Dividing the hosts into four size-groups (small, medium-sized, large and extra large), the pairwise comparison of prevalence and mean abundance of the new and literary data) showed differences according to host size. The differences in the composition of the parasitic faunas and in the prevalence of parasites, observed between the small tunas from the Tyrrhenian Sea and the medium-sized tunas from the Adriatic Sea, Levantine Sea and the North-East (NE) Atlantic Ocean, indicated that these groups form discrete units. The parasite fauna of the large tunas from the Sea of Sardinia is the richest among the bluefin tuna populations of the Mediterranean and the NE Atlantic, due to the presence of species not found elsewhere in bluefin tunas, such as Caligus coryphaenae, Capsala magronum and C. paucispinosa. This fact and the prevalence of some parasites of this group (lower than those of medium-sized fish from the NE Atlantic and higher than the small and medium-sized tunas from the Mediterranean) suggest that the large-sized tuna group in the western Mediterranean is formed by Mediterranean resident tunas (poorly infected), and by tunas migrating from the Atlantic Ocean (heavily infected).

:  Incidental catches in pelagic longline fishing pose a serious threat to sea turtle populations throughout the world's seas and oceans. In this work, carried out in the framework of the EC‐DG‐Fisheries 98/008 project, information on sea turtle catch rates from swordfish and albacore longline fishing activities observed in Italian waters off the Ionian Sea during 1999 and 2000, are reported. In addition, biometric data, health status, and tagging return rate of sea turtles captured are provided. A total of 200 sea turtles were caught (198 loggerhead turtles and 2 green turtles), comprising 0.5–15.7% of the total catch in number of individuals. The estimates of the sea turtles caught by the total fishing effort of both longlines in the whole study area were 1084 specimens in 1999 (95% CI = 667–1502) and 4447 specimens in 2000 (95% CI = 3189–5705). Although all sea turtles were released alive, nearly half of them had hooks that could not be removed and remained deeply embedded in the digestive tract.

We analysed the genetic diversity of Melicertus kerathurus (Penaeidae), a commercially valuable penaeid shrimp that is distributed in the Mediterranean Sea and eastern Atlantic Ocean. We examined the polymorphism of a 494 bp DNA segment of the mitochondrial COI region in 173 individuals, sampled in nine Mediterranean and two Atlantic samples, covering the whole range of the species from the tropical waters of the Gulf of Guinea to the eastern part of the Mediterranean Sea. The mean nucleotide and haplotype diversities were pi=0.00275 and h=0.718, respectively, for the global data set, with the highest values occurring in the African samples and the lowest in the Adriatic Sea. A clear sample differentiation was found (Fsub(st)=0.194), but this did not reflect a geographical pattern and there were only faint traces of an Atlantic-Mediterranean subdivision. Mismatch analysis and a high significant negative value of Tajima's D suggested that M. kerathurus is not at mutation drift-equilibrium, but underwent a recent expansion after a period of low effective sample size. A postglacial recolonisation of the Mediterranean from an Atlantic refuge could be hypothesised based on these data.

:  The demersal multispecies trawl fishery in the western Mediterranean Sea has a poor selectivity; large numbers of juvenile fish are caught when using the legislated 40‐mm diamond mesh cod end. The selectivity of a flexible sorting grid with 20‐mm bar spacing (BS20) installed in front the conventional trawl cod end was investigated. The standard covered cod end method was used. Data was adequate for analyzing the selectivity of European hake Merluccius merluccius, poor cod Trisopterus minutus, greater forkbeard Phycis blennoides and Norway lobster Nephrops norvegicus. The selectivity of the 20‐mm sorting grid was compared with the performance of 40‐mm diamond (DM40) and square mesh (SM40) cod ends. The effect of a guiding funnel on the performance of the grid (BS20‐f) was also explored. Finally, the potential changes in yield per recruit (Y/R) and biomass per recruit (B/R) after implementing a sorting grid were explored. An overall improvement in the 50% selection length (L50) with all four species was substantial when comparing the BS20 to the DM40. Higher improvement in L50s was achieved when the grid was equipped with the guiding funnel. When comparing the performance of the BS20‐f to the SM40, there was no marked difference in L50s. The Y/R and B/R, however, are substantially higher with BS20‐f for poor cod and about the same for European hake. BS20 compared to SM40 achieved lower Y/R and B/R for all four species; the smallest difference was observed for Norway lobster. Further development is required if the sorting grid is to be introduced into commercial fisheries.