The origin of the Sardinian Blue, Pseudophilotes barbagiae (Lycaenidae): Out-of-Europe or Out-of-Africa?

Trabajo presentado en el XIXth European Congress of Lepidopterology, celebrado en Radebeul (Alemania) del 27 de septiembre al 2 de octubre de 2015.The island of Sardinia is characterized by an extraordinary richness of endemic species, evolved as a result of its geographic position and geological history. Here, we try to reconstruct the evolutionary history of the endemic Sardinian blue butterfly, P. barbagiae de Prins and van der Poorten 1982, using the DNA barcoding region of the COI mitochondrial gene. The species is restricted to a few slopes in the mountainous areas of the island, and has been described as distinct from the continental and Corsican P. baton by characteristics of the male genitalia and wing markings. We analyzed 11 individuals of P. barbagiae and compared them with all Eu- ropean and north African congeneric species: a group of 77 sequences including P. baton (Corsica, Italy, France, Spain), P. vicrama (Romania, Turkey, Kazakhstan, Russia) and P. panoptes (Spain), as well as several BINs containing 20 sequences of P. abencerragus (Spain, Morocco, Tunisia, Portugal), 10 sequences of P. bavius (Romania, Russia) and 4 sequences of P. fatma (Morocco). The Bayesan phylogenetic tree showed that the group with P. baton, P. vicrama and P. panoptes forms a well-supported clade, but DNA barcodes do not distinguish these three species. The largest interspecific distance (4.8%) was found between P. fatma and P. baton ­ P. vicrama ­P. panoptes group, while the smallest (1.2%) was between P.abencerra­ gus and P. barbagiae. The latter also forms a well-supported monophyletic group and has closer affinity to P. abencerragus (1.2%) than to P. baton – P. vicrama – P. pa noptes group (1.8%). Two hypotheses on a European versus an African origin of P. barbagiae will be presented in the light of genetic and biogeographic data. This study will contribute to the emerging picture of butterfly diversification in the Palearctic region, and contribute to our understanding of the evolution of endemism in the European butterfly fauna.N