Phylogeographyc inferences from the mtDNA variation of the three-toed skink, Chalcides chalcides (Reptilia: Scincidae)

Genetic diversity was analyzed in Chalcides chalcides populations from peninsular Italy, Sardinia, Sicily and Tunisia by sequencing 400 bp at the 50 end of the mitochondrial gene encoding cytochrome b (cyt b) and by restriction fragment length polymorphism (RFLP) analysis of two mitochondrial DNA segments (ND-1/2 and ND-3/4). The results of the phylogenetic analysis highlighted the presence of three main clades corresponding with three of the four main geographical areas (Tunisia, Sicily and the Italian peninsula), while Sardinia proved to be closely related to Tunisian haplotypes suggesting a colonization of this island from North Africa by human agency in historical times. On the contrary, the splitting times estimated on the basis of cyt b sequence data seem to indicate a more ancient colonization of Sicily and the Italian Peninsula, as a consequence of tectonic and climatic events that affected the Mediterranean Basin during the Pleistocene. Finally, the analysis of the genetic variability of C. chalcides populations showed a remarkable genetic homogeneity in Italian populations when compared to the Tunisian ones. This condition could be explained by a rapid post-glacial expansion from refugial populations that implied serial bottlenecking with progressive loss of haplotypes, resulting in a low genetic diversity in the populations inhabiting the more recently colonized areas

Ecology and conservation of the Mediterranean trout in the central Apennines (Italy)

The Mediterranean brown trout (Salmo trutta complex) is one of the freshwater fish species complex at greater risk of extinction in the Mediterranean area. The introduction of alien invasive species and their interaction with the native fauna represent some of the major threats to the survival of this species. Currently, the genetic variability of the Mediterranean trout (Salmo trutta complex) is being compromised by the introgressive hybridization with the Atlantic trout (Salmo trutta Linnaeus, 1758). Therefore, it is necessary to gain further knowledge on genetic and demographic characteristics of Mediterranean trout populations, that, combined with environmental and angling data, will allow to undertake sound conservation strategies. The aims of the present study were to analyze: i) the demographic characteristics of the Mediterranean trout in seven central Apennine river basins where native populations are threatened by stocking with the domestic trout of north Atlantic origin; ii) the influence of both environmental parameters and different fishery management strategies on the status of native trout populations. The project focuses on 14 sites included in the Natura 2000 EU wide network of nature protection areas, established under the 1992 Habitat Directive. A total of 25 watercourses were investigated for a total of 32 sampling sites. A census of the fish fauna was carried out by electrofishing at each sampling location. Fish and environmental data were collected in spring and autumn 2014. The results obtained in the present research allowed us to detect the presence of three residual Mediterranean trout populations with a high degree of genetic integrity in the study area. The native trout populations were characterized by higher abundances and higher adult density values. Well-structured native populations with higher legal-size specimens density and poor body conditions in terms of relative weight were observed in the no-fishing areas, probably due to the presence of intraspecific competition phenomena. The environmental analysis confirmed the key role played by the geological characteristics of the central Apennines in shaping the introgression levels observed in the wild trout populations, while the recovery of the water quality appears decisive in the development of management strategies aimed at their conservation

Haplotype characterization of a stranded common minke whale calf (Balaenoptera acutorostrata lacépède, 1804): Is the mediterranean sea a potential calving or nursery ground for the species?

The stranding of a suckling calf of Common Minke Whale (Balaenoptera acutorostrata) on the coast near Salerno (Campania, Southern Italy) is reported. The molecular analysis of a partial sequence of the mitochondrial DNA control region shows that the animal bore a haplotype identical to haplotype Ba169 considered as typical of individuals from North Atlantic population. Historical data and our results suggest the possibility that the Mediterranean Sea might be a potential calving or nursery ground for this species

Searching for a stock structure in <i>Sardina pilchardus</i> from the Adriatic and Ionian seas using a microsatellite DNA-based approach

En el presente trabajo se ha investigado la variabilidad genética de la sardina europea en el mar Adriático y Jónico con el objetivo de detectar la posible existencia de estructura genética entre y dentro de ambas cuencas. El análisis de la variabilidad genética en ocho loci microsatélites detectó una desviación respecto al equilibrio HW por un exceso de homocigotos en algunas de las muestras estudiadas. La estima del nivel de diferenciación interpoblacional, realizada mediante AMOVA, qST and rRST, y descriptores Bayesianos, resultó no significativa para las muestras analizadas. Estos datos concuerdan con los obtenidos en estudios previos basados en alozimas y marcadores mitocondriales y contradicen la anterior identificación de dos subpoblaciones en el mar Adriático en base a datos morfológicos y reproductivos

Karyological Characterization of the Endemic Iberian Rock Lizard, Iberolacerta Monticola (Squamata, Lacertidae): Insights into Sex Chromosome Evolution

[Abstract] Rock lizards of the genus Iberolacerta constitute a promising model to examine the process of sex chromosome evolution, as these closely related taxa exhibit remarkable diversity in the degree of sex chromosome differentiation with no clear phylogenetic segregation, ranging from cryptic to highly heteromorphic ZW chromosomes and even multiple chromosome systems (Z1Z1Z2Z2/Z1Z2W). To gain a deeper insight into the patterns of karyotype and sex chromosome evolution, we performed a cytogenetic analysis based on conventional staining, banding techniques and fluorescence in situ hybridization in the species I. monticola, for which previous cytogenetic investigations did not detect differentiated sex chromosomes. The karyotype is composed of 2n = 36 acrocentric chromosomes. NORs and the major ribosomal genes were located in the subtelomeric region of chromosome pair 6. Hybridization signals of the telomeric sequences (TTAGGG)n were visualized at the telomeres of all chromosomes and interstitially in 5 chromosome pairs. C-banding showed constitutive heterochromatin at the centromeres of all chromosomes, as well as clear pericentromeric and light telomeric C-bands in several chromosome pairs. These results highlight some chromosomal markers which can be useful to identify species specific diagnostic characters, although they may not accurately reflect the phylogenetic relationships among the taxa. In addition, C-banding revealed the presence of a heteromorphic ZW sex chromosome pair, where W is smaller than Z and almost completely heterochromatic. This finding sheds light on sex chromosome evolution in the genus Iberolacerta and suggests that further comparative cytogenetic analyses are needed to understand the processes underlying the origin, differentiation and plasticity of sex chromosome systems in lacertid lizards.Xunta de Galicia; PGIDIT03RFO10301PRXunta de Galicia; PGIDIT06RFO10301PRItalia. Ministero dell'istruzione, dell'università e della ricerca; PRIN 200

Haplotype characterization of a stranded &lt;em&gt;Balenoptera physalus&lt;/em&gt; (Linnaeus, 1758) from Ancona (Adriatic sea, central Italy)

&lt;strong&gt;Caratterizzazione aplotipica di una balenottera comune spiaggiata presso&#13; Ancona (Mare Adriatico, Italia centrale).&lt;/strong&gt;&#13; &lt;strong&gt;Riassunto&lt;/strong&gt;&#13; La sequenza della regione di controllo del DNA mitocondriale di un esemplare di balenottera comune (&lt;em&gt;Balaenoptera physalus&lt;/em&gt;) spiaggiata presso Ancona (Mare Adriatico) viene descritta e confrontata con quelle note per la specie.&#13; L’aplotipo ottenuto è risultato identico a quello descritto per il Mar Ligure, permettendo di ipotizzare spostamenti fra l’area tirrenica e l’Adriatico centro-settentrionale

Chalcides chalcides (Linnaeus, 1758)

tassonomia e biologia della specie Chalcides chalcides in Itali

Standard karyotypes of two populations of the <em>Scincus scincus</em> complex from Tunisia and Morocco (Reptilia: Scincidae)

A study on chromosomes of two Scincus populations attributed to S. scincus and S. albifasciatus was carried out by conventional Giemsa staining. Both samples showed the same diploid number of 2N = 32 and identical chromosome morphology. Therefore, these populations seem to be lacking in chromosome changes that could act as barriers to gene flow. However, because speciation in lizards is not always associated with chromosome repatterning, the taxonomic status of “scincus” and “albifasciatus” forms remains unsettled