The morphological and genetic structure of Western Mediterranean trout Salmo cettii inhabiting basins in Sardinia was completed to assist the design of its conservation programmes. Genetic analysis of protein-coding LDH-C1 plus sequencing mitochondrial control region gene and analyses of morphological characters described 253 specimens from seven localities in two basins in Southwest Sardinia. Nuclear and mitochondrial analyses revealed all of the fish were pure-bred native S. cettii, with no introgression from allochthonous S. trutta. The novel 18 mtDNA control region haplotypes were clustered in an 'insular' clade, strictly related to the Adriatic haplogroup, and depicted a radial network around two ancestral haplotypes. Completion of discriminant analysis using data on body pigmentation and quantitative morphologic parameters revealed three phenotypic groups within the fish. Each population and phenotype, characterised by high values of nucleotide and haplotype diversity, were not genetically differentiated and not geographically structured according to the two hydrological basins. Geometric morphometric analysis, based on 15 landmarkers, revealed pronounced and highly significant differences in body shape morphology between populations, suggesting S. cettii is locally adapting to extreme environmental conditions and so future management plans for these populations should treat the two basins as distinct morphological units.

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Started in October 2003 and concluded in September 2006, the project has been realized thanks to the financial support of the European Community and the co-financial support of Lombardy Region-Environment Quality Department, with the participation, as a partner, of South Oglio Park.The objective of the project was the conservation of the adriatic sturgeon population found in the Ticino River and in the middle reach of the Po River, blocked there by the Isola Serafini dam on the Po river that prevents the fish from migrating to and from the Adriatic sea.Sporadic but reliable records provide evidence of the presence in the Ticino River of a spawning population that passes its life cycle in freshwater, and so is called a landlocked population.This population, with little information about its real size and status, could actually represent one of the last groups, if not the last, of the original population of Acipenser naccarii that once inhabited the Po Basin.That is why it is necessary to have a conservation project that would define the best strategy to manage and protect the species, and carry out the activities necessary for its preservation.