ABSTRACT
The distribution of the genetic diversity and the population structure of Pagellus erythrinus were analysed using mitochondrial control region sequences and cytochrome b restriction profiles in a total of 128 and 508 individuals, respectively, that were collected from 15 sampling sites in the central Mediterranean Sea and from one site in the Atlantic Ocean. No population genetic structure was detected within the central Mediterranean and thus, the commonly recognized transition zones in the area do not seem to affect population connectivity. The comparison between the Mediterranean samples and the single Atlantic sample suggests weak differentiation between the two basins. Three mitochondrial lineages were identified, each including individuals from almost every sampling site. The haplotype and nucleotide diversity values, mismatch distribution and demographic parameters indicate that the sympatry of these lineages can be ascribed to a period of isolation followed by genetic divergence, population expansion and secondary contact, all of which are likely to be associated with climatic oscillations that occurred during the middle and late Pleistocene.
Acknowledgements
We thank the MEDITS coordinators and all of our colleagues for their invaluable help with sample collection, specifically Maria Teresa Spedicato and Giuseppe Lembo, COISPA (Bari); Angelo Cau, Department of Life and Environmental Sciences, Cagliari University; Corrado Piccinetti, Department of Biological, Geological and Environmental Sciences, Bologna University; Angelo Tursi, Department of Biology, Bari University; Fabio Fiorentino, Coastal Marine Environment Institute, Mazara del Vallo; Mohamed Salah Romdhane, INAT/Université de Carthage, Tunisia; and Rafaela Barros Paiva, Centro de Oceanografia, Universidade de Lisboa, Portugal. The authors are grateful to Valentina Milana and Paolo Colangelo, Department of Biology and Biotechnology C. Darwin, Sapienza University of Rome, for their critical reading and suggestions.
Disclosure statement
No potential conflict of interest was reported by the authors.