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Twenty-five species of cetaceans have been reported throughout the Mediterranean Sea, eight of them are commonly distributed in the whole basin and are regularly found beached or adrift in the sea. Stranded animals are frequently found in poor conservation status, preventing reliable identification; identification is thus often based solely on morphological features. Therewith, molecular tools are especially useful to provide taxonomic identification. In this work, a four-enzymes PCR-RFLP in silico protocol, based on a fragment of the mitochondrial gene cytb, has been designed for cetacean species occurring in the Mediterranean Sea. Moreover, beached or floating specimen samples belonging to the eight common species have been tested in the laboratory, providing evidence that this approach represents a reliable, cost- and time-effective tool for their specific identification.

In animals, doubly uniparental inheritance (DUI) is a major exception to the common strict maternal inheritance of mitochondria. To date, DUI has only been found in many bivalve species, but its distribution is still unclear. Given the great species richness of the class, much effort is needed to further investigate the occurrence of DUI in unsampled species. A compelling evidence of DUI is generally the presence of a sex-linked heteroplasmy, where two divergent mitochondrial lineages are found: One is isolated from the male germline, and the other one is isolated from the female germline and, normally, from the soma of both sexes. In the present study, we investigated the sex-linked heteroplasmy in the razor clam Solen marginatus Pulteney, 1799 and in the lagoon cockle Cerastoderma glaucum (Bruguière, 1789) using two mitochondrial markers (cox1 and rrnL). We found evidence of DUI in the species S.marginatus, with a divergence up to 21% for the rrnL gene, but not in C.glaucum. Moreover, our phylogenetic reconstruction includes all the available data for heterodont species with sex-linked heteroplasmy and suggests multiple origins of DUI in this subclass, as well as the presence of DUI in other species of the genus Solen.

The production of cupped oysters is an important component of European aquaculture. Most of the production relies on the cultivation of the Pacific oyster Crassostrea gigas, although the Portuguese oyster Crassostrea angulata represents a valuable product with both cultural and economic relevance, especially in Portugal. The authors of the present study investigated the genetic diversity of Portuguese oyster populations of the Sado estuary, both from natural oyster beds and aquaculture facilities, through cox1 gene fragment sequencing. Then, a comparison with a wide dataset of cupped oyster sequences obtained from GenBank (up to now the widest available dataset in literature for the Portuguese oyster) was performed. Genetic data obtained from this work confirmed that the Pacific oyster does not occur in the natural oyster beds of the Sado estuary but showed that the species occasionally occurs in the oyster hatcheries. Moreover, the results showed that despite the founder effect and the bottleneck events that the Sado populations have experienced, they still exhibit high haplotype diversity. Risks are arising for the conservation of the Portuguese oyster reference populations of the Sado estuary due to the occurrence of the Pacific oyster in the local hatcheries. Therefore, researchers, local authorities, and oyster producers should work together to avoid the loss of this valuable resource.

Despite their ecological and economical relevance, a lack of data is still occurring about the distribution, abundance, bioaccumulation and risks for consumption of some edible bivalves. The present study has been carried out in the Venice Lagoon taking into account three bivalve species to investigate i) the possible relationship among the biological features-distribution, abundance and bioaccumulation patterns- of razor clams (Solen marginatus Pulteney, 1799), Manila clams (Ruditapes philippinarum Adams and Reeve, 1850) and lagoon cockles (Cerastoderma glaucum Poiret, 1789) and the hydrological features, namely sediment physico-chemical characteristics and contamination; ii) their specific role as bioindicators of inorganic contamination; iii) the possible risks for human health associated with the consumption of these edible bivalves. Results showed that species distribution and abundance, especially for razor clams, was mainly influenced by environmental conditions and sediment granulometric composition, above metal(loid) contamination. The contamination patterns were different among species, as Manila clam generally showed higher bioaccumulation values for most of the metal(loid)s, whilst lagoon cockles preferentially accumulated Ni. Eventually, a serious concern exists for the human consumption, for all species and investigated sites regarding As. This study will raise attention on the effects of bioaccumulation of inorganic pollutants by edible bivalves and risks for consumers' safety, especially concerning razor clams and cockles, for which a critical lack of data on metal(loid) bioaccumulation occurs from the Northern Adriatic Sea.

Rare earth elements (REEs) are gaining growing attention in environmental and ecotoxicological studies due to their economic relevance, wide range of applications and increasing environmental concentrations. Among REEs, special consideration should be given to Gadolinium (Gd), whose wide exploitation as a magnetic resonance imaging (MRI) contrast agent is enhancing the risk of its occurrence in aquatic environments and impacts on aquatic organisms. A promising approach for water decontamination from REEs is sorption, namely through the use of macroalgae and in particular Ulva lactuca that already proved to be an efficient biosorbent for several chemical elements. Therefore, the present study aimed to evaluate the toxicity of Gd, comparing the biochemical effects induced by this element in the presence or absence of algae. Using the bivalve species Mytilus galloprovincialis, Gd toxicity was evaluated by assessing changes on mussels’ metabolic capacity and oxidative status. Results clearly showed the toxicity of Gd but further revealed the capacity of U. lactuca to prevent injuries to M. galloprovincialis, mainly reducing the levels of Gd in water and thus the bioaccumulation and toxicity of this element by the mussels. The results will advance the state of the art not only regarding the effects of REEs but also with regard to the role of algae in accumulation of metals and protection of aquatic organisms, generating new insights on water safety towards aquatic wildlife and highlighting the possibility for resources recovery.

The concentrations of inorganic, organic and total carbon, and some sedimentary parameters (sediment density, fines, pH, and shell fragments), have been analyzed in surface sediments of the Venice Lagoon since 1987. Environmental scenarios, characterized by different anthropogenic impacts, have been considered, especially in the central basin where more information is available. Data collected in 2009 in the lagoons and ponds of Po Delta, in Comacchio Valleys and Pialassa della Baiona have been also considered and analyzed together with those recorded in the whole Venice Lagoon in 2011. The results show a strong correlation of the inorganic carbon (Cinorg) with the carbonatic or siliceous origins of the sediments and changes of both Cinorg and organic carbon (Corg) according to different anthropogenic impacts, especially eutrophication and clam-fishing activities. Higher sediment density, grain-size, and pH were associated to good-high ecological conditions and the higher presence of inorganic carbon of biological origin (shell fragments and calcified macroalgal fragments). Conversely, Corg, which is associated to eutrophic conditions, was strongly affected by the sediment disturbance and the presence of high concentrations of bivalves which enhance its consumption.

Marine bioinvasions require integrating monitoring tools with other complementary strategies. In this study, we collected information about the invasive alien crab Callinectes sapidus in Italy, Croatia and Montenegro, by means of online questionnaires administered to recreational fishers (n = 797). Our records matched the current distribution of the species: C. sapidus resulted far more common in the Adriatic/Ionian than in the Tyrrhenian/Ligurian sector. Most respondents rated the species as ‘occasional’ or ‘rare’. Moreover, the more C. sapidus was considered to be abundant, the more fishers tended to perceive it as a negative disturbance over fisheries and the environment. Our findings suggest that C. sapidus is more common than previously thought in most of the study area, and it could have reached the levels of a true invasions in the south-eastern Adriatic Sea. This experience demonstrates that online questionnaires can be appropriate tools to effectively engage stakeholders in alien species monitoring.

Gadolinium (Gd) is one of the most commercially exploited rare earth elements, commonly employed in magnetic resonance imaging as a contrast agent. The present review was performed aiming to identify the Gd concentrations in marine and freshwater environments. In addition, information on Gd speciation in the environment is discussed, in order to understand how each chemical form affects its fate in the environment. Biological responses caused by Gd exposure and its bioaccumulation in different aquatic invertebrates are also discussed. This review was devoted to aquatic invertebrates, since this group of organisms includes species widely used as bioindicators of pollution and they represent important resources for human socio-economic development, as edible seafood, fishing baits and providing food resources for other species. From the literature, most of the published data are focused on freshwater environments, revealing concentrations from 0.347 to 80 μg/L, with the highest Gd anomalies found close to highly industrialized areas. In marine environments, the published studies identified a range of concentrations between 0.36 and 26.9 ng/L (2.3 and 171.4 pmol/kg), reaching 409.4 ng/L (2605 pmol/kg) at a submarine outfall. Concerning the bioaccumulation and effects of Gd in aquatic species, most of the literature regards to freshwater species, revealing concentration ranging from 0.006 to 0.223 μg/g, with high variability in the bioaccumulation extent according to Gd complexes chemical speciation. Conversely, no field data concerning Gd bioaccumulation in tissues of marine species have been published. Finally, impacts of Gd in invertebrate aquatic species were identified at different biological levels, including alterations on gene expression, cellular homeostasis, shell formation, metabolic capacity and antioxidant mechanisms. The information here presented highlights that Gd may represent an environmental threat and a risk to human health, demonstrating the need for further research on Gd toxicity towards aquatic wildlife and the necessity for new water remediation strategies. published

We present a comprehensive review of the available global literature on the genetics and genomics of marine fish invasions. Overall this review provides data from 66 species belonging to 39 families, collected from 80 published studies on both WoS (Web of Science) and Scopus databases. We found that studies on alien fishes focused on specific geographic areas, mainly the Mediterranean region. Furthermore, most studies restricted their approach to describe patterns of cryptic diversity and/or the development of novel markers, whilst the genetic structure of introduced populations and the genetic mechanisms driving the invasion processes were mostly neglected. The majority of studies on marine fishes reveal similar genetic diversity levels in both native and introduced ranges, suggesting massive or multiple introductions. Indeed, cases of introduced populations showing evidence of bottlenecks were rare. Genetic arrangements are not explained by taxonomic group or reproductive strategy but recent studies reveal rapid evolutionary changes associated with invasive lineages, opening new grounds to investigate mechanisms of adaptation in the natural environment. Finally, the potential of marine fish invasions as a model to test evolutionary responses to rapid environmental changes is further discussed.

The accumulation of Posidonia oceanica dead leaves on the beaches of the Mediterranean shores is a natural phenomenon. They are either temporary or permanent structures (banquettes) and represent a valuable resource, with important ecosystem functions including coastal protection against erosion. Nevertheless, the perception of these plant accumulations by the different stakeholders (beach managers, local administrations and tourists) is often negative, they consider these deposits a malevolent waste to be removed, rather than a natural and valuable component of the coastline. We propose an integrated/beneficial management model for posidonia deposits, called ECOLOGICAL BEACH, firstly proposed in France, and recently implemented and applied in Italy. The model promotes the preservation of posidonia beach casts on site, with a balanced coexistence of natural and anthropic elements. The model fosters the several important ecosystem services of the beach casts and contributes to coastal preservation. To successfully spread the model, several activities must be implemented: a regulatory framework, the collection of data about the occurrence of beach casts, management protocols and educational programs. The most important activity is the educational one, based on the dissemination of the ecological and economic value of the beach casts, aimed at switching the perception of this phenomenon towards positive appraisal.

Shellfish farming and shellfish harvesting have been practiced for a long time in the Ria de Aveiro coastal lagoon (Portugal). Among commercial bivalves, Manila clam Ruditapes philippinarum represents one of the most important species inhabiting this coastal system. Introduced in Portugal in 1984, naturalised R. philippinarum clam populations have been subjected to several pressures that may threaten this resource sustainable management: illegal fishing, harvesting in chemically polluted sites with impacts on human health and lack of control in terms of productivity with the risk of a progressive decline of the biomass. On behalf of the ASARISAFE project (with the title Safety and sustainable management of valuable clam product in Portugal and China) the environmental quality of Manila clam harvesting sites was evaluated, focusing on inorganic pollution and health status of clams in terms of bioaccumulation as well as biochemical performance. Seasonal sampling campaigns were conducted in six R. philippinarum harvesting areas evaluating inorganic pollution levels, in clam's tissues, sediment and water. Clams biochemical performance in terms of metabolism, energy reserves and oxidative stress was also assessed. The results obtained showed that mercury (Hg) and arsenic (As) were the elements with the highest BAF (Bioaccumulation factor) values, but contamination levels in tissues and sediments varied among sampling areas and seasonal campaigns. The amount of clams consumed per week to exceed Provisional Tolerable Week Intake (PTWI, kg) was the lowest for As, revealing that less 0.05 kg of clams was enough to exceed PTWI. However, the results obtained further demonstrated that the clam's biochemical performance was not responding to tissues contamination levels but were closely related to seasons, with distinct metabolic capacity and oxidative stress levels among distinct sampling periods during the year.

Elite athletes are those who represent their sport at such major competition as the Olympic Games or World contests. The most outstanding athletes appear to emerge as a result of endogenous biologic characteristics interacting with exogenous influences of the environment, often described as a 'Nature and Nurture' struggle. In this work, we assessed the contribution given by 4 genes involved in muscles development (MSTN) and behavioural insights (5HTT, DAT and MAOA) to athletic performances. As for neurotransmission, 5HTT, DAT and MAOA genes have been considered as directly involved in the management of aggressiveness and anxiety. Genotypes and allelic frequencies of 5HTTLPR, MAOA-u VNTR, DAT VNTR and MSTN K153R were determined in 50 elite athletes and compared with 100 control athletes. In this work we found a significant correlation between the dopamine transporter genotype 9/9 and allele 9 and elite sport performances. On the contrary, no association was found between muscle development regulation or serotonin pathway and elite performances. Our data, for the first time, suggest a strong role of dopamine neurotransmitter in determining sport success, highlighting the role of emotional control and psycological management to reach high-level performances.

The Manila clam Ruditapes philippinarum – synonym Venerupis philippinarum (Adams and Reeve, 1850) is now one of the top 5 most commercially valuable bivalve species worldwide. Originally from the Indo-Pacific region, it has been introduced in many countries for fisheries and aquaculture, including estuarine environments along Atlantic and Mediterranean European coasts. Yet despite its commercial value and widespread distribution, the precise origins of stocks remain speculative and the genetic diversity of introduced populations is poorly known. Thus, the aim of this work was to collect mtDNA COI (Cytochrome oxidase I) gene sequences from 5 European countries with Manila clam stocks and compare them with native Asian populations to evaluate their genetic diversity and identify possible routes of invasion. The COI gene sequencing supported a strong founder effect in the European populations with 3 main haplotypes occurring at high frequencies, derived from Japan. However, high haplotype diversity was also observed due to the occurrence of 10 rare haplotypes. This supports hypotheses (i) there have been additional, previous unrecorded, introductions as previously hypothesized by analysis of 16S rDNA, and (ii) there has been a limited loss of genetic diversity in introduced populations, as previously suggested by microsatellite data. This is the first genetic comparison of Manila clam populations introduced in to Europe with native clams. Genetic data herein presented are fundamentally important for the traceability of clam products and stock management programmes and will also inform discussion on the potential resilience of exploited Manila clam populations.

The impacts of seawater acidification and salinity shifts on metabolism, energy reserves, and oxidative status of mussels have been largely neglected. With the aim to increase the current knowledge for the mussel Mytilus galloprovincialis a 28-day chronic test was conducted during which mussels were exposed to two pH (7.8 and 7.3; both at control salinity 28) and three salinity (14, 28 and 35, at control pH, 7.8) levels. After exposure to different conditions, mussels electron transport system activity, energy reserves (protein and glycogen content) carbonic anhydrase activity, antioxidant defences and cellular damage were measured. Results obtained showed that mussels exposed to seawater acidification presented decreased metabolic capacity that may have induced lower energy expenditure (observed in higher glycogen, protein and lipids content at this condition). Low pH condition induced the increase of carbonic anhydrase activity that was related to acid-base balance, while no significant activation of antioxidant defence mechanisms was observed resulting in higher LPO. Regarding the impacts of salinity, the present study showed that at the highest salinity (35) mussels presented lower metabolic activity (also related to lower energetic expenditure) and an opposite response was observed at salinity 14. Carbonic anhydrase slightly increased at stressful salinity conditions, a mechanism of homeostasis maintenance. Lower metabolic activity at the highest salinity, probably related to valves closure, helped to mitigate the increase of LPO in this condition. At low salinity (14), despite an increase of antioxidant enzymes activity, LPO increased, probably as a result of ROS overproduction from higher electron transport system activity. The present findings demonstrated that Mytilus galloprovincialis oxidative status and metabolic capacity were negatively affected by low pH and salinity changes, with alterations that may lead to physiological impairments namely on mussels reproductive output, growth performance and resistance to disease, with ecological and economic implications. Indicators: Physiological and biochemical changes in Mytilus galloprovincialis in response to low pH and salinity changes

The rock partridge, Alectoris graeca, is a polytypic species declining in Italy mostly due to anthropogenic causes, including the massive releases of the closely related allochthonous chukar partridge Alectoris chukar which produced the formation of hybrids. Molecular approaches are fundamental for the identification of evolutionary units in the perspective of conservation and management, and to correctly select individuals to be used in restocking campaigns. We analyzed a Cytochrome oxidase I (COI) fragment of contemporary and historical A. graeca and A. chukar samples, using duplicated analyses to confirm results and nuclear DNA microsatellites to exclude possible sample cross-contamination. In two contemporary specimens of A. graeca, collected from an anthropogenic hybrid zone, we found evidence of the presence of mtDNA heteroplasmy possibly associated to paternal leakage and suggesting hybridization with captive-bred exotic A. chukar. These results underline significant limitations in the reliability of mtDNA barcoding-based species identification and could have relevant evolutionary and ecological implications that should be accounted for when interpreting data aimed to support conservation actions.

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.

Introduction of non-indigenous taxa by anthropogenic activities may lead to the generation of hybrid forms and cause genetic pollution of native species. Populations of different Salmo species are threatened in Italy by hybridization and introgression caused by allochthonous lineages introduced since historical times. In particular, Salmo marmoratus is currently sympatric with domestic lineages of Salmo trutta in most of its native geographical range and reproductive interfecundity between the two taxa is seriously threatening the genetic purity of the endemic species. To fulfill conservation purposes and fisheries management, an investigation based on single and multilocus DNA fingerprinting was carried out both to assess marble trout genetic diversity and the method’s amenability to restocking practices. RFLPs (Restriction Fragments Length Polymorphisms) and SNPs (Single Nucleotide Polymorphisms) in mitochondrial 16 S rDNA, D-loop, and nuclear LDH-C1* sequences were genotyped in more than 350 samples collected from different hatcheries in Northern Italy. The combination of the three markers allowed the selection of putative pure individuals of S. marmoratus to be submitted to additional highly polymorphic AFLPs (Amplified Fragment Length Polymorphisms) analyses. Additional benefits of AFLPs over other techniques emerged in connection with their potential power for fish stock identification. In fact, 52% of all analyzed samples were potentially pure marble trout, 4% were pure Atlantic trout and 44% were hybrids showing different combinations of haplotypes/genotypes. The combined approach demonstrated improved resolution to reveal hybridization not detected by classical diagnostic markers, and to select breeders for reintroduction programs.

Manila clam Ruditapes philippinarum represents an important economic resource of Italian aquaculture. However, especially for Venice lagoon, health and environmental risks should be evaluated. A multidisciplinary approach was used. In particular, local production chain analysis and end-user requirements were investigated to assess manila clam safety and traceability in Northern Adriatic Sea. Moreover, the molecular and biochemical techniques demonstrated a good quality of the investigated farming sites, due to the absence of biotoxins. Molecular markers provided informations on the population genetics and specific genetic traits of Ruditapes philippinarum in Northern Adriatic Sea, which was investigated for the first time. The complexity of all these informations was simplified in a single useful tool: a database containing all the informations about the seafood product.

In this work, we present molecular barcoding results obtained in 69 processed fish products belonging to 27 teleost species traded in Italian commercial markets during 2008. DNA barcoding using direct sequencing of about 900 bp of mitochondrial genes cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b) revealed uncorrect labelling in 22 samples (32%). Among substituted species, 18 (26%) were serious frauds under both economic and nutritional points of view. In some cases, frauds concerned species of major conservation regard and reported in the IUCN and CITES directories. Results add further concern on the trading of processed fish products in Italy from both health and conservation points of view.

In 2006 an unusual find of Procambarus clarkii, today considered one of the most dangerous exotic crayfish, was made within the preserved brackish Mediterranean biotope “Palude di Torre Flavia” (Rome, Italy). Here the investigation on the population structure and dynamics of P. clarkii inhabiting this brackish wetland is presented in an attempt to describe the life history pattern in this type of habitat. The present study showed that this species has a lower growth rate and higher longevity than other studied European P. clarkii populations, and that it can damage brackish habitats and human livelihoods. The main results of this study chiefly concern the differences found between several life-history parameters of the studied population and those obtained in previous studies. These results showed the high ecological plasticity of P. clarkii, indicate the need to intervene before the species spreads further in brackish water, for the conservation of Mediterranean coastal habitats.

Biological invasions inflict damage to the ecology, economy, and human health, and pose serious threats to the native communities. Among the many invasive taxa, crayfish have attracted much attention by scientists and policy makers. Recently, an established population of an alien species of crayfish, new for Italy, was found in the Natural Preserve of “Laghi di Ninfa” (central Italy). Based on morphological and genetic evidence (molecular barcoding of COI and 16S rDNA), we classified it at subspecies level as the Parastacidae Cherax destructor destructor, native to Australia. Its introduction possibly occurred at the end of the 1980s but the species seems to be still confined in the preserve. The low temperature of the adjacent waters may be a barrier against its natural spreading but not against its intentional translocation into natural waters by man. Because of the invasive history of C. destructor, eradication of this population is urgent and still economically profitable.

* Corresponding author Received 9 February 2009; accepted in revised form 30 March 2009; published online 24 April 2009 Abstract The red swamp crayfish, Procambarus clarkii, is the most abundant invasive crustacean decapod in Italy. Evidence is however emerging for the presence of other Cambaridae that are erroneously assigned to the P. clarkii taxon. The marbled crayfish, belonging to a still uncertain species of the genus Procambarus, has been found for the first time in Italy in the Canale Maestro della Chiana (Tuscany, Central Italy), where it lives in sympatry with a large P. clarkii population. Although a single specimen was found, this record is particularly relevant due to the parthenogenetic reproductive habit of the marbled crayfish. However, molecular analyses based on COI barcoding did not reveal any differentiation within the P. clarkii population and excluded any form of hybridization between the two species. We will shortly discuss new pathways of invasive species and the threats posed by parthenogenetic species, even though they seem to be still sporadic.

Although the symbionts of non-vertebrate metazoans have received scarce attention, scientific interest has recently increased as these symbionts can spread diseases and alter the diversity of the ecosystem where hosts are introduced. We report here a symbiont newly described by molecular markers and observed on the yabby Cherax destructor Clark, 1936, collected in Italian freshwaters. Preliminary morphological observations were performed and a species identification was proposed using molecular techniques. In particular, a 644-bp long 28S rDNA fragment was successfully sequenced and could be aligned for the entire sample set. The minimum spanning network identified two haplotypes clustered into a single haplogroup (H1) together with Temnosewellia minor Haswell, 1888 reference sequences. Considering the introduction of temnocephalans, this represents the third discovery of alien crayfish symbionts in Italian freshwaters, but the first obtained by molecular data. Outside Europe, there are only few records of alien temnocephalans worldwide, introduced with the crayfishes from Australia. The occurrence of this new temnocephalid species and the great number of potential hosts species inhabiting Italian freshwaters suggest that the Italian peninsula might have many undescribed temnocephalid populations/species.

L’introduzione di specie animali e la transfaunazione costituiscono attualmente una grave minaccia per le specie autoctone, seconda solo alla distruzione degli habitat. In questo contesto, bene si inserisce l’attuale situazione, riscontrata negli ultimi anni nei sistemi idrici del Lazio, relativa alla presenza dei decapodi dulcacquicoli alloctoni Procambarus clarkii, Orconectes limosus (cambaridi originari del Nord America) e Astacus leptodactylus (astacide proveniente dall’Europa orientale). Lo studio della distribuzione nel territorio regionale ha permesso di mettere in evidenza alcune differenze relative alla presenza delle tre specie in esame: Orconectes limosus ed Astacus leptodactylus si trovano solo in alcune aree circoscritte, puntiformi; Procambarus clarkii, invece, ha una distribuzione molto più ampia nel territorio regionale. Questa ricerca ha confermato la notevole plasticità ecologica la forte capacità invasiva e di adattamento ai nuovi ambienti, grazie al rapido accrescimento, allo sfruttamento delle risorse trofiche più svariate ed alla frequenza ed ampiezza dei periodi riproduttivi. Questo può creare un disequilibrio all’interno dell’ecosistema portando a danni irreversibili, non solo di natura ecologica ma in qualche caso anche di natura economica (più facile ed immediata da rilevare). Pertanto, è possibile indicare alcune linee guida relative alle attività di gestione nell’area presa in esame. L’eradicazione di Procambarus clarkii sembra essere un intervento di difficile attuazione data la sua presenza e le continue segnalazioni fornite da persone di diversa estrazione (ricercatori, pescatori professionisti e sportivi, appassionati, etc.), in particolare nel reticolo idrico dell’agro pontino, intricato sistema di irrigazioni di campi agricoli. Un’attività di contenimento che preveda uno sforzo in campo da parte di tutti gli enti predisposti alla salvaguardia dell’ambiente è comunque auspicabile. Per le altre due specie, la loro presenza limitata fa della eradicazione un intervento più facilmente attuabile. In ogni caso, deve essere evitata la diffusione di queste specie, fenomeno continuamente mantenuto soprattutto dalla loro commercializzazione. Ciò può avvenire sensibilizzando l’opinione pubblica, effettuando un costante controllo sull’intero territorio, incrementando la ricerca di base e supportando tali sforzi con una legislazione adeguata, in grado di regolamentare l’introduzione ed il trattamento delle specie aliene, normativa che al momento non risulta soddisfacente.

Manila clam Ruditapes philippinarum – synonym Venerupis philippinarum (Adams and Reeve, 1850) – is one of the most successful marine invaders, being introduced worldwide for aquaculture and fisheries. Genetic diversity and structure of its populations are largely unknown, especially in the invaded environments. Herein we present molecular genetic data on 12 introduced Manila clam populations in Italy, Spain, and Portugal from both Mediterranean (Adriatic) and Atlantic sampling sites. The phylogenetic information was investigated by the direct sequencing of 16S mitochondrial DNA. Results of mtDNA analyses showed the occurrence of 11 haplotypes for European introduced populations, as a consequence of multiple founder effects from different source populations. Rp hap1 was the most frequent, shared among all populations. The other 10 haplotypes were rare and distributed at local scale, in agreement with what was observed in other invasive bivalves. Biogeographic and phylogenetic analyses based on 16S rDNA of introduced Manila clam populations showed a complex scenario, dominated by multiple pools of individuals coming from different sources, as a consequence of multiple introductions.

The systematic is still unresolved for the genus Squalius (Cyprinidae, Leuciscinae), a rich group of small to large fishes widely distributed throughout Europe. The distinction of one of the Italian narrowly endemic species, Squalius albus (Bonaparte, 1838), described for the area surrounding lake Trasimeno, from the more common and widespread Squalius squalus (Bonaparte, 1837) is doubtful. The application of integrative taxonomy, with DNA taxonomy and quantitative morphometric, using both living and preserved individuals collected from lake Trasimeno before Squalius sp. restocking, allowed us to explicitly test for the identity of the two species in the complex. COI barcoding data, used for phylogenetic reconstructions, underlined that two clades may exist in the complex; nevertheless, DNA taxonomy (ABGD and GMYC) and morphometrics show no statistical support for their identity as separate species. Moreover, during our survey of the genetic diversity of the Italian Squalius, we provided further support for the species status of Squalius lucumonis, and found evidence of the occurrence in Southern Italy of another chub species, Squalius vardarensis (Karaman, 1928), previously known only from the Southern part of the Balkan Peninsula.

Seven Italian populations of twaite shad Alosa fallax from Northern and Central Italy were investigated to assess genetic diversity by Cytochrome b (Cytb) gene sequencing. The two ecotypes historically referred to landlocked and anadromous populations were investigated for the first time from a genetic point of view, to clarify their phylogenetic relationships. Moreover, results obtained from populations coming from separated Adriatic and Tyrrhenian basins were compared with data assessed in samples of allis shad Alosa alosa from the Atlantic basin. All the Italian samples were recognized at species level as A. fallax, differing for five mutations from A. alosa. The analyses confirmed the occurrence of a single phylogenetic lineage and of a single species within Italian waters, in both landlocked and migratory populations. The minimum spanning network identified six haplotypes for A. fallax and two haplotypes for A. alosa. The neighbour-joining tree and the maximum likelihood on the Cytb gene sequences confirmed two distinct lineages for A. alosa and A. fallax, without evidence of a separation at specific level within the A. fallax group. A weak separation due to incipient population differentiation was detected between anadromous and landlocked Italian populations, supporting the idea of a recent separation. The molecular data herein collected do not support the existence of the already controversial incipient species Alosa agone. Despite this, the two ecotypes could be considered as different management units from a conservation viewpoint.

The coastal lagoons of the Northern Adriatic Sea are among the most worldwide productive locations of Manila clam Ruditapes philippinarum. Although introduced in Italy in 1983 from the Indo-Pacific, fishing and exploitation of Manila clam improved during the years as Italy became the leading country in Europe for production of this shellfish. Despite its commercial importance, genetic structure of R. philippinarum in Northern Adriatic Sea has not been previously investigated. Here we present the first genetic study on Manila clam populations inhabiting a Mediterranean area, assessed by both mitochondrial (16S rDNA) and nuclear DNA (microsatellite loci). Our study showed that this species has a limited genetic differentiation at the mitochondrial level, but a higher rate of genetic diversity can be identified by polymorphic markers as microsatellites. In particular, out of 28 alleles, 7 private ones were recorded for the Venice Lagoon populations, 2 for those of Scardovari and one for the Po River Delta populations. These molecular markers suggest the occurrence of at least two different introduction events from different recruitment stocks, representing a powerful tool not only to assess genetic diversity of an introduced species, but also helpful information to manage aquaculture and fishery stocks, and to warrant food quality, safety and for the authentication of shellfish products, and traceabilty path.

A fish population of the carp family Cyprinidae with atypical phenotypic characteristics was observed in one of the main catchments of the Pollino National Park, a valuable, protected area in southern Italy. In this area, the Italian roach Rutilus rubilio (Bonaparte, 1837), a native endemic fish of Tyrrhenean regions, has been introduced in sympatric conditions with Squalius squalus (Bonaparte, 1837) and Telestes muticellus (Bonaparte, 1837). A molecular investigation was carried out to assess the genetic identity of the population with a view to conservation. Direct sequencing of a cytochrome b gene fragment was performed based on 30 individuals of cyprinid fish with atypical phenotype, in addition to 30 S. squalus, 10 T. muticellus, and 30 R. rubilio pure individuals collected in different Italian regions, which served as reference samples. Multiple sequence alignments demonstrated that 50% of atypical-cyprinid haplotypes were maternally inherited from either S. squalus or R. rubilio. No contribution by T. muticellus was determined. Our results indicate an intergeneric hybridization event between S. squalus and R. rubilio, as a consequence of trans-introduction activities of alien species.

The Manila clam is emerging as a relevant species for the Portuguese market. The present work was conducted in the Tagus estuary to evaluate 1) the metals and As content in the sediments of the Tagus estuary, especially on those areas subjected to Manila clam harvesting 2) the metals and As content in clams, and the risk associated with their consumption 3) the physiological and biochemical responses of the clam to metals and As contamination, and its possible role as a pollution bioindicator in the estuarine environment. The most contaminated sediments were identified nearby industrial areas, nevertheless clams collected in low contaminated areas showed high metals and As concentrations. The condition index, glycogen content, membrane oxidative damage, biotransformation enzymes and metallothioneins showed consistent responses to metals and As content in clams. Results emphasize the need for the development of a management plan for the species exploitation in the Tagus estuary.