SPECIATION OF THE GENUS BARBUS IN THE NORTH MEDITERRANEAN BASIN - RECENT ADVANCES FROM BIOCHEMICAL GENETICS

On the basis of population genetic studies, this article proposes a sy stematic and evolutionary redefinition of some of the Barbus species o ccurring in the north Mediterranean basin. The comparative value of en zymatic and nucleic acid markers is discussed. The various evolutionar y branches of the genus Barbus reflect the main migrations of the fres hwater fish fauna. The phylogeny thus allows the origin of the species to be reconstituted. Species occurring in the north of the Mediterran ean basin are positioned along an intercontinental gradient frequently having different levels of ploidy: these include diploid species, tet raploid species belong to the subgenus Barbus and the hexaploid specie s of the subgenus; Labeobarbus. An integrated study of genetics, karyo logy, palaeontology, morphology and parasitology is suggested as the m eans of assessing the value of various evolutionary hypotheses propose d in the literature.