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The potential of native entomopathogenic nematodes for the control of the brown marmorated stink bug Halyomorpha halys was evaluated in experimental trials in Georgia. Two Georgian strains of Heterorhabditis bacteriophora (HRB, GEO) and Steinernema borjomiense and two Italian strains of H. bacteriophora (HRB, IT) and S. apuliae were used in laboratory assays (22°C and 80% RH) at concentrations of 1000, 500 and 200 infective juveniles (IJs) per adult H. halys. The mortality of tested insects was estimated from the third day after treatment. Differences in mortality of the tested insect were observed between Georgian and Italian strains. At the highest concentration (1000 IJs/adult), mortality (%) of H. halys induced by Georgian strains HRB and S. borjomiense was 53.3 and 40, respectively, at 500 IJs/adult 40 and 33.3, and at 200 IJs/adult 33.3 and 13.3, respectively. Italian strains HRB (IT) and S. apuliae proved more suppressive against the tested insects, with mortality rates of 95.5 and 60, 93.3 and 40 and 73.3 and 33.2%, at concentrations of 1000, 500 and 200 IJs/adult of H. halys, respectively. The present study provides further insights in selection of promising EPN strains to be used against this harmful insect pest, although further studies to test their efficacy under field conditions are needed.

Steinernema feltiae belongs to the feltiae-kraussei-oregonensis group, clade III, and is an ubiquitarian species of entomopathogenic nematode. It is found in all types of soil and in all types of habitat. Species identification in the entomopathogenic nematodes genera Steinernema is a very complex task, given the broad variability of both morphological and biological traits within populations of a single species. To accomplish this, molecular techniques have been adopted which, however, require additional knowledge. Particularly relevant would be the possibility of testing in a reliable way the variability between different populations of the same species, which might represent different strains with different biological properties. During numerous samplings in Italy, several strains of S. feltiae were isolated. In this paper we analyze the intraspecific variability of the main morphometric and biological data of juveniles and males of 50 Italian populations of S. feltiae. The aim of our work was to determine if morphometric and biological analysis were useful to identify characters having significant diagnostic value, allowing to reliably discriminate among strains. Seven characters routinely computed for morphology (5 morphometrics for infective juveniles, spicula and gubernaculum shapes for males) and 2 biological performances (time to achieve adult stage, reproduction and progeny) were considered. The results showed extreme variability from both morphological and biological points of view

13 pages, 6 figures, tables, In the deep sea, the sense of time is dependent on geophysical fluctuations, such as internal tides and atmospheric-related inertial currents, rather than day-night rhythms. Deep-sea neutrino telescopes instrumented with light detecting Photo-Multiplier Tubes (PMT) can be used to describe the synchronization of bioluminescent activity of abyssopelagic organisms with hydrodynamic cycles. PMT readings at 8 different depths (from 3069 to 3349 m) of the NEMO Phase 2 prototype, deployed offshore Capo Passero (Sicily) at the KM3NeT-Italia site, were used to characterize rhythmic bioluminescence patterns in June 2013, in response to water mass movements. We found a significant (p < 0.05) 20.5 h periodicity in the bioluminescence signal, corresponding to inertial fluctuations. Waveform and Fourier analyses of PMT data and tower orientation were carried out to identify phases (i.e. the timing of peaks) by subdividing time series on the length of detected inertial periodicity. A phase overlap between rhythms and cycles suggests a mechanical stimulation of bioluminescence, as organisms carried by currents collide with the telescope infrastructure, resulting in the emission of light. A bathymetric shift in PMT phases indicated that organisms travelled in discontinuous deep-sea undular vortices consisting of chains of inertially pulsating mesoscale cyclones/anticyclones, which to date remain poorly known

Aquaporin-8 (AQP8) is a membrane channel permeable to water and ammonia. As AQP8 is expressed in the inner mitochondrial membrane of several mammalian tissues, we studied the effect of the AQP8 expression on the mitochondrial transport of ammonia. Recombinant rat AQP8 was expressed in the yeast Saccharomyces cerevisiae. The presence of AQP8 in the inner membrane of yeast mitochondria was demonstrated by subcellular fractionation and immunoblotting analysis. The ammonia transport was determined in isolated mitochondria by stopped flow light scattering using formamide as ammonia analog. We found that the presence of AQP8 increased by threefold mitochondrial formamide transport. AQP8-facilitated mitochondrial formamide transport in rat native tissue was confirmed in liver (a mitochondrial AQP8-expressing tissue) vs. brain (a mitochondrial AQP8 non-expressing tissue). Comparative studies indicated that the AQP8-mediated mitochondrial movement of formamide was markedly higher than that of water. Together, our data suggest that ammonia diffusional transport is a major function for mitochondrial AQP8.

The Atlantic horse mackerel ( Trachurus trachurus ) is a semi-pelagic fish species with a wide geographical distribution and commonly found on the continental shelf. In recent years, the species has received some attention due to its ecological role in pelagic food webs. Stable isotope of nitrogen and carbon (δ 15 N and δ 13 C) and Stomach Content Analysis (SCA) of T. trachurus were adopted as tools to provide necessary knowledge on its feeding habits in the Strait of Sicily. The strong correlation found between δ 15 N and δ 13 C values with body length, together with significant ontogenetic shift evidenced by SCA, could be associated to changes in food availability, which in turn is triggered by environmental conditions. Spatial distribution of T. trachurus in the study area, mainly for small and medium size specimens, is linked to lower temperature, salinity and Photosynthetically Active Radiation (PAR sat ) values with higher aggregations on the Adventure Bank (i.e., an area characterized by periodic upwelling events). Larger size specimens mostly inhabited shallower waters characterized by higher temperature, salinity and PAR values, typical of the central-eastern part of the study area. Our results support the hypothesis that feeding behavior of T. trachurus is strictly linked to environmental factors (i.e. chiefly oceanographic conditions of the water column and day duration) that in turn influences the distribution of its prey. Findings can supply knowledge needed for improving fish stock management and promoting plans able to take into account also local ecosystem analysis.

Trophic ecology of adults of European sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) was examined and compared among various regions of central Mediterranean Sea. Carbon and nitrogen stable isotope analyses (delta C-13 and delta N-15) were adopted as a tool to determine changes in feeding behaviour of adults of sardines and anchovies. In the study period (summer) a clear geographical pattern was recognized in the isotopic composition of both species, with an increasing trend northward. The highest variations in isotopic signal were linked to the geographical positions of the samples and, especially, between pairs of areas: South Sicily/South Campania and Gulf of Gaeta/South Elba. Higher isotope values were found in the anchovies and sardines caught in northern Tyrrhenian Sea, while lower values were mostly estimated in the southern region. Higher carbon and nitrogen isotopes may reflect a more coastal behaviour of both species, being C-13-enriched source from benthic primary producers in addition to phytoplankton. Variations in the nitrogen isotope ratio may reflect not only differences in the trophic level of prey species, but also variations in the baseline level of food webs. Our results support the hypothesis that feeding behaviour of both species is directly or indirectly influenced by local factors, or by resource partitioning based on zooplankton size. Findings can supply knowledge needed for improving fish stock management and promoting plans able to take into account also local ecosystem analysis. (C) 2016 Elsevier Ltd. All rights reserved.

Dark marine habitats are often characterized by a food-limited condition. Peculiar dark habitats include marine caves, characterized by the absence of light and limited water flow, which lead to reduced fluxes of organic matter for cave-dwelling organisms. We investigated whether the most abundant and common cave-dwelling fish Apogon imberbis has the potential to play the role of trophic vector in Mediterranean marine caves. We first analysed stomach contents to check whether repletion changes according to a nycthemeral cycle. We then identified the prey items, to see whether they belong to species associated with cave habitats or not. Finally, we assessed whether A. imberbis moves outside marine caves at night to feed, by collecting visual census data on A. imberbis density both inside and outside caves, by day and by night. The stomach repletion of individuals sampled early in the morning was significantly higher than later in the day. Most prey were typical of habitats other than caves. A. imberbis was on average more abundant within caves during the day and outside during the night. Our study supports the hypothesis regarding the crucial trophic role of A. imberbis in connecting Mediterranean marine caves with external habitats.

16 pages, 3 figures, 8 tables, electronic supplementary material http://dx.doi.org/10.1007/s10530-015-0868-5, The introduction of Red Sea species through the Suez Canal has caused dramatic alteration of Eastern Mediterranean marine communities, however changes at the level of trophic interactions remain poorly understood. Capitalizing on this spectacular bioinvasion, we used stable isotope analysis to depict the novel fish food web occurring in the Eastern Mediterranean, off the Lebanese coast. Multivariate analyses were performed on six trophic groups contrasting the δ15N–δ13C ratios of native (MED) versus non-indigenous (Lessepsian-LES) species. Community-wide aspects of trophic structure were explored by means of recently developed quantitative metrics, such as the average distance to centroid and the standard ellipse area. Although the trophic positions of Lessepsian and native species were comparable, native fishes generally showed a greater trophic diversity than Lessepsians, the latter being mainly located in the central region of the available trophic space. We argue that the original trophic niche of native species has widened out due to the shift they have made towards less preferred food items, whilst highly competitive invaders are exploiting more energetic resources. In the absence of historical data, our observations agree with the idea of a rapid change of the Eastern Mediterranean food web, driven by niche displacements through trophic competition, This project was partially funded by the European Commission FP7 project VECTORS (ref. Oceans 2010-2-266445) and by the University Research Board (URB) (DDF 111030/188111 and 111030/288132) of the American University of Beirut (Lebanon)

The dusky spinefoot (Siganus luridus) has spread through much of the eastern Mediterranean since its introduction in 1920. In the present study, we monitored the abundance of this invader around the island of Linosa (Strait of Sicily), where the species was first recorded in 2003. Data were periodically collected along two temporal windows, 2005–06 and 2012–15, by both underwater visual census and surface snorkelling. Local ecological knowledge was investigated to gain complementary information. Both approaches highlighted significant proliferation of this tropical invader, with an average abundance of 0.36 individuals per 250m2 across the 0–30-m depth range. Dense aggregations of more than 100 adult individuals were observed in September 2015, and a coherent spatial structure at the small scale (

13 pages, 2 figures, 4 tables, Stable isotope analysis (SIA) of carbon and nitrogen is now a common tool to investigate trophic relationships and food-web structure in aquatic ecosystems. However, species-specific and tissue-specific lipid content sometimes hinders the correct interpretation of δC and δN values because lipids are C-depleted with respect to proteins, and thus tissue lipid extraction is generally invoked. We assessed the effects of lipid extraction on δC and δN compositions and C:N ratios of muscle, liver (or hepatopancreas) and gonads of three common Mediterranean deep-sea species with different locomotory activity, buoyancy mechanisms and feeding modes: the benthic-feeder shrimp Aristeus antennatus, the nektobenthic-feeder shark Galeus melastomus and the pelagic-feeder fish Micromesistius poutassou to evaluate both the effect of lipid extraction on SIA data and the validity of δC lipid correction models. Results showed that the effect of lipid extraction is not unique but some common patterns can be identified. Lipid extraction resulted in increased δN values in the liver and the muscle and in decreased δN values in the gonads, in increased δC values in all the tissues of the three species, except in the hepatopancreas of A. antennatus, and in decreased C:N ratios. The magnitude of the changes was species- and tissue-specific. We assessed the validity of δC correction equations for lipid content in muscle and liver tissues available from literature in the species from this study. Such equations provided corrected δC values equivalent to those obtained through lipid extraction when applied to a species with similar characteristics (i.e., taxon, behavior, etc.) to those for which the equations were designed. Our results for muscle tissue showed that not one of the equations tested was valid for the deep-sea shark G. melastomus, and we propose a species-specific model with a fairly feasible model efficiency. Besides, tissue-specific equations for liver in G. melastomus provided non-significant differences between δC and δC values, but all model efficiencies were fairly low. Thus, lipid extraction trials on elasmobranch muscle and liver tissue to determine effects on δC and δN values on a species-by-species basis are recommended. Our research together with a comprehensive literature review on this topic, highlights that there is no accepted or mandated standard of treatment for lipids when using stable isotope analyses, The authors acknowledge funding from Spain's National Research Programme for research project BIOMARE (CTM2006–13508-CO2–02/MAR) and ANTROMARE (CTM2009–12214-C02–01/MAR) projects

The non-indigenous crabs Percnon gibbesi (H. Milne Edwards, 1853) and Callinectes sapidus (Rathbun, 1896) (Crustacea, Decapoda, Portunidae) are reported from Genoa and La Spezia, respectively, in the Ligurian Sea at the northern rim of the Mediterranean Sea. Both specimens were collected by fishermen who then brought them to the attention of professional scientists. This illustrates the importance of engaging local communities in detecting non-indigenous species and monitoring their spread. © 2017 The Author(s). Journal compilation & 2017 REABIC.

16 pages, 6 figures, 4 tables, 1 appendix, The influence of mesoscale physical and trophic variables on deep-sea megafauna, a scale of variation often neglected in deep-sea studies, is crucial for understanding their role in the ecosystem. Drivers of megafaunal assemblage composition and biomass distribution have been investigated in two contrasting areas of the Balearic basin in the NW Mediterranean: on the mainland slope (Catalonian coasts) and on the insular slope (North of Mallorca, Balearic Islands). An experimental bottom trawl survey was carried out during summer 2010, at stations in both sub-areas located between 450 and 2200m water depth. Environmental data were collected simultaneously: near-bottom physical parameters, and the elemental and isotopic composition of sediments. Initially, data were analysed along the whole depth gradient, and then assemblages from the two areas were compared. Analysis of the trawls showed the existence of one group associated with the upper slope (US=450-690m), another with the middle slope (MS=1000-1300m) and a third with the lower slope (LS=1400-2200m). Also, significant differences in the assemblage composition were found between mainland and insular slopes at MS. Dominance by different species was evident when the two areas were compared by SIMPER analysis. The greatest fish biomass was recorded in both areas at 1000-1300m, a zone linked to minimum temperature and maximum O2 concentration on the bottom. Near the mainland, fish assemblages were best explained (43% of total variance, DISTLM analysis) by prey availability (gelatinous zooplankton biomass). On the insular slope, trophic webs seemed less complex and were based on vertical input of surface primary production. Decapods, which reached their highest biomass values on the upper slope, were correlated with salinity and temperature in both the areas. However, while hydrographic conditions (temperature and salinity) seemed to be the most important variables over the insular slope, resource availability (gelatinous zooplankton and Calocaris macandreae) predominated and explained 59% of decapod assemblage variation over the mainland slope. Both fish and decapods were linked to net primary production recorded over the mainland 3 months before sampling, while the delay between the input of food from the surface and fish abundance was only 1 month on the insular slope. Our results suggest that trophic relationships over insular slopes probably involve a shorter food chain than over mainland slopes and one that is likely more efficient in terms of energy transfer. © 2013 Elsevier Ltd., This study was carried out within the framework of the Spanish funded ANTROMARE project (ref. CTM2009-12214-C02-01/MAR)

The rising impact of invasive species and climate change on Mediterranean fish biodiversity highlight the urgency to evaluate the current status of natural assemblages. Here we investigated the rocky-reef fish of Malta and Lampedusa (Strait of Sicily, Mediterranean Sea), two islands of high biogeographical importance subjected to a different level of protection and anthropic pressure. By using underwater visual census, a total of 192 counts were performed in May–June and September–October 2007 using a hierarchical spatial design and four depth layers. Overall, 23 families and 61 different taxa were recorded. Out of them, two highly invasive species were censused (i.e. Siganus luridus and Fistularia commersonii) with relatively low abundances. Native Labridae and Sparidae shape the assemblage structure of both islands, and thermophilic species such as Sparisoma cretense and Thalassoma pavo occur with high densities. The fish assemblages of Malta and Lampedusa were relatively similar in species composition, richness and total abundance. Nevertheless, multivariate analysis depicted significant differences between these two islands, mainly attributable to the unevenness of Labridae. Significant differences in the size distribution of the most abundant species were detected between islands, with parallel variation across time. The pattern of spatio-temporal variability of the whole assemblage structure strongly resembled that of nekto-benthic fish, hence pointing out the relevance of this guild as an indicator species group in future monitoring activity. This study will serve as a current baseline against which future changes in the central Mediterranean fish assemblages can be assessed.

14 pages, 5 figures, 3 tables, The trophic ecology (diets, stable isotope composition) and life cycle (gonado-somatic, GSI, and hepato-somatic, HSI, indices) of Aristaeomorpha foliacea were analysed seasonally (in May, June, and November 2012 and January 2013) off southeast Turkey (Levantine Basin), over the slope at 442-600 m depth. Aristaeomorpha foliacea females were mature in June, suggesting gonad maturity was somewhat delayed off southeast Turkey compared to other areas in the Eastern Mediterranean. The HSI of A. foliacea was highest in May and June (8.2% of body weight) for males and both immature and mature females, sharply lower in November (3.5%) and then increasing again in winter (7.1%). Stomach fullness (F) showed a tendency similar to HSI in both females and males, increasing from May to June. Aristaeomorpha foliacea had rather low δ15N (6.68‰ to 8.26‰) off southeast Turkey, with females having higher δ15N with increasing size. The δ13C signal (-14.85 to -14.68‰) indicated that diet was mainly though not exclusively based on zooplankton (pelagic shrimps and small myctophids of 1.3-4.5 mm TL, cnidarians, hyperiids and pteropods). The increase of A. foliacea remains in A. foliacea guts and of some benthic prey (polychaetes, bivalves, gastropods) after the reproductive period would explain the moderate depletion of δ13C in spring-summer. The greatest changes in the diet occurred between periods of water mass stratification (June and November) and periods of water mass homogeneity (May and January), with greater consumption of zooplankton in the latter season. Aristaeomorpha foliacea seems to have lower reproductive capacity (GSI 5.6%) than other deep-water species of penaeidae living in shallower (Parapenaues longirostris) and deeper waters (Aristeus antennatus). The species has a more specialized zooplankton diet, exploiting short, more efficient trophic chains, which could be an advantage explaining its dominance in oligotrophic areas of the Central-Eastern Mediterranean, including the Turkish slope, This research was performed in collaboration with, and partially financed by the MICYT project ANTROMARE (CTM2009-12214-C02-01-MAR)

13 pages, 5 figures, 5 tables, The trophic ecology, energy and reproductive states of the deep-water shrimp Aristaeomorpha foliacea, widely distributed along the slopes of the Mediterranean Sea Basins, were analysed in eight areas spread along ca. 3000km in order to identify patterns in the habitat conditions supporting the species. From W to E the areas were situated between the north side of Eivissa (39°12'N, 1°20'E, in the Balearic Basin) and off Mersin, Turkey (36°15'N, 34°19'E, in the Levantine Sea). Trends identified mainly as a function of longitude from west to east were: (i) higher δ15N, parallel to δ15N shifts in the top 200m of the water column for particulate organic N (Pantoja et al., 2002). The δ15N trend indicates that the deep trophic web, i.e. A. foliacea at 400-600m, reflects the δ15N signal of the photic zone; (ii) a similar significant trend of δ13C, related with exploitation of pelagic versus benthic resources by A. foliacea in each area (i.e. by local variability of terrigenous inputs via submarine canyons). More depleted δ13C was found at mid-longitudes (Tyrrhenian Sea and Sicily Channel) linked to higher consumption of macroplankton prey (Pasiphaea spp., euphausiids and mesopelagic fishes). The feeding intensity (gut fullness, F) and prey diversity (J) of A. foliacea were related, according to generalized linear models, with the temperature and salinity of intermediate waters, variables in turn associated with latitude and longitude. Both F and J were higher in areas with greater shrimp density. The optimal ecological habitat of A. foliacea appears to be located in the Tyrrhenian Sea and the Sicily Channel, where we found the highest F, the greatest trophic diversity and A. foliacea in the best biological condition (i.e. with higher hepato-somatic index, HSI). These are also the areas with the highest densities of A. foliacea. In contrast, in the western Mediterranean Sea (Balearic Basin and the southern Balearic Islands), where A. foliacea has low densities, the shrimp showed generally lower values of trophic indicators and biological condition. © 2014 Elsevier Ltd., This research was performed and financed within the framework of the MICYT project ANTROMARE (CTM2009-12214-C02-01-MAR). In addition, this study was possible thanks to some material collected on oceanographic cruises (MEDITS_IT10 and 11, IDEADOS09, IDEADOS10) and by commercial trawlers

Bioluminescence refers to the production of ecologically functional light by living organisms. It is widespread in the marine environment, where it occurs in a broad range of phyla. The deep pelagic ocean is the largest biome on earth and is chronically under-sampled. Underwater camera systems offer a rapid sampling method for this zone. In the current study, the ICDeep (Image Intensied Charge Coupled Device for Deep-sea research) profiler was used to record digital video of bioluminescent organisms through the deep water column. This work proposes a new automatic detection and counting methods for bioluminescent organisms represented as ashes within video data acquired through the camera based on computer vision algorithms. The proposed method has been validated by a ground truthed sequence of bioluminescent events resulting in a high correct detection rate and real time processing execution.