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Natural history museums are irreplaceable tools to study and preserve the biological diversity around the globe and among the primary actors in the recognition of species and the logical repositories for their type specimens. In this paper we surveyed the consistency of the preserved specimens of amphibians and reptiles housed in the major Italian scientific collections, and verified the presence of threatened species according to the IUCN Red List, including the Extinct (EX), Extinct in the Wild (EW), Critically Endangered (CR), Endangered (EN), and Vulnerable (VU) categories. Altogether, we analyzed 39 Italian zoological collections. We confirmed the presence of one extinct reptile (Chioninia coctei) and five extinct or extinct in the wild amphibian species (Atelopus longirostris, Nectophrynoides asperginis, Pseudophilautus leucorhinus, P. nasutus, and P. variabilis). Seven CR amphibians, fourteen CR reptile species and the extinct skink C. coctei are shared by more than one institution. Museums which host the highest number of threatened and extinct amphibian species are respectively Turin (17 CR and 1 EX), Florence (13 CR and 1 EX), and Trento (15 CR and 1 EW), while for reptiles the richest museums are those from Genoa (15 CR and 1 EX), Florence (11 CR and 1 EX), and Pisa (7 CR). Finally, we discussed the utility of natural history museums and the strategies to follow for the implementation of their functionality. [ABSTRACT FROM AUTHOR]

The role of the south-western Alps as a corridor for Mediterranean trout (Salmo trutta complex Linnaeus, 1758) was evaluated in order to understand the influence of the last glacial events in shaping the spatial distribution of the genetic diversity of this salmonid. For this, the allochthonous hypothesis of a man-mediated French origin (19th century) of the Mediterranean trout inhabiting the Po tributaries in the Italian side of the south-western Alps was tested. A total of 412 individuals were analysed at the mitochondrial control region. The phylogenetic classification was carried out by using a Median-Joining Network analysis. Mismatch pair-wise analysis, molecular dating and Kernel density distribution analysis of the main mitochondrial lineages were evaluated to compare past demographic dynamics with the current spatial distribution of genetic diversity. The main outcomes resulted strongly in agreement with a biogeographic scenario where the south-western Alps acted as a unidirectional corridor that permitted the colonization of the upper Durance (Rhône River basin) by trout from the Po River basin. Therefore, the Mediterranean trout should be considered as native also along the Italian side of the south-western Alps and the allochthonous hypothesis should be rejected. [ABSTRACT FROM AUTHOR]

Background. The Mediterranean swordfish stock is overfished and considered not correctly managed. Elucidating the patterns of the Mediterranean swordfish population structure constitutes an essential prerequisite for effective management of this fishery resource. To date, few studies have investigated intra-Mediterranean swordfish population structure, and their conclusions are controversial. Methods. A panel of 20 microsatellites DNA was used to investigate fine-scale population structuring of swordfish from six main fishing areas of the Mediterranean Sea. Results. This study provides evidence to reject the hypothesis of a single swordfish population within the Mediterranean Sea. DAPC analysis revealed the presence of three genetic clusters and a high level of admixture within the Mediterranean Sea. Genetic structure was supported by significant FST values while mixing was endorsed by the heterozygosity deficit observed in sampling localities indicative of a possible Wahlund effect, by sampling admixture individuals. Overall, our tests reject the hypothesis of a single swordfish population within the Mediterranean Sea. Homing towards the Mediterranean breeding areas may have generated a weak degree of genetic differentiation between populations even at the intra-basin scale. [ABSTRACT FROM AUTHOR]

Mediterranean brown trout is subject to several serious threats such as pollution, water abstraction, habitat alteration and especially genetic introgression with domestic strains used for stocking activities. Despite this latter issue has largely been debated by scientists, local managers and stakeholders for decades, official stocking practices with domestic trout still persists in several countries (Italy included), even if there are laws explicitly prohibiting introduction of organisms of non-local origin. Probably, the last opportunity to conserve native brown trout populations is represented by protected areas. Therefore, in the present study, we aimed to verify the role of the Nature 2000 network and a national park as valid tools to guarantee the survival of native brown trout in the Apennines. Partial mitochondrial DNA control region sequence analysis and genotyping of the locus LDH-C1* and 11 microsatellites were used to investigate the genetic diversity of three rivers from central Italy. For all rivers investigated a temporal analysis of introgression was also carried out. The genetic diversity of three domestic stocks was included in the sampling design for comparison. The main results of this study indicated that: (i) the genetic diversity of brown trout in central Italy is very complex and (ii) its conservation is seriously threatened by genetic introgression phenomena still ongoing. The only samples showing no introgression or a decrease in genetic introgression were those isolated by the presence of natural and/or artificial barriers to fish movements rather than protected by inhabiting rivers within the Natura 2000 network. This observation prompts an important reflection on issues concerning fluvial continuity restoration and suggests that barrier removal should be undertaken with caution in order to avoid the concrete risk of domestic trout spreading that could promote additional loss of native brown trout biodiversity. [ABSTRACT FROM AUTHOR]

Copyright of Knowledge & Management of Aquatic Ecosystems is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Knowledge & Management of Aquatic Ecosystems is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Satellite DNAs represent a preponderant portion of eukaryotic genomes, and despite the ample literature on satDNAs of eukaryotes little is known about these repetitive elements in reptiles. Studies on reptiles satellite DNAs have been mainly focused on lacertid lizards and only one aimed at characterising these repetitive elements in skinks. Here, the isolation and characterisation of a satellite DNA in two populations of the ocellated skink, Chalcides ocellatus (Forskål, 1775), is presented. The repetitive element isolated is located at centromeres of all chromosomes of the complement, shows a tendency towards AT enrichment (53.5%), and contains short motifs that are common in centromeric satellites of eukaryotes (TG/CA, GAAA). The satellite shows an extremely low evolutionary rate (0.13% per million year) that make it unsuitable as a phylogenetic probe to assess the genetic differentiation of the populations investigated, that show a deep genetic divergence at mitochondrial level. The influence of satellite location on chromosomes and chromosomal morphology are invoked to explain this unusually slow mutation rate. [ABSTRACT FROM AUTHOR]

Genetic diversity of four populations of Chalcides mertensi (Klausewitz, 1954) from Tunisia was analyzed by means of the Restriction Fragment Length Polymorphism (RFLP) analysis of two fragments of mitochondrial DNA (mtDNA) encompassing NADH dehydrogenase subunits 1 and 2 (ND-1/2) and NADH dehydrogenase subunits 3, 4 and 4L (ND-3/4). Phylogenetic relationships between haplotypes were inferred by analysing the sequence of 396 base pairs at the 5' end of the mitochondrial gene encoding cytochrome b and a segment of 12S rRNA gene (386 bp). The results of this study highlighted a pronounced genetic divergence between the populations from northern (Ain Soltane and Tabarka) and southern (Kasserine and Sidi Bouzid) Tunisia, that the phylogenetic analysis recovered as two distinct taxonomic entities. These two groups of populations can therefore be ascribed to two distinct taxa, with southern populations probably representing the typical C. mertensi, whereas northern individuals are likely to represent a new species of grass swimming Chalcides. The divergence between these two taxonomic entities can be referred to palaeogeographic and palaeoclimatic events that have affected northwestern Africa during the last 10 Million years. The analysed populations show a low genetic variability that can be related to the past climatic and geologic events and the colonization processes that took place with environmental amelioration, and to the peripheral position of these populations in the distributional range of the species. However, a more exhaustive study, including Algerian and Moroccan skink populations will be necessary in order to clarify these issues. [ABSTRACT FROM AUTHOR]