Population – genetic structure on European anchovy (Engraulis encrasicolus, Linnaeus, 1758) (Osteichthyes: Engraulide) from Mediterranean Basin and Atlantic Ocean

Abstract

         Muscle proteins of the European anchovy Engraulis encrasicolus L. were analyzed using starch gel electrophoresis and isoelectric focusing on thin polyacrylamide ampholine gel. Twenty-two protein loci were analyzed and polymorphism was found in six of them. Based on genetic-biochemical data, we hypothesize that there are two anchovy subspecies, European and African. The former inhabits the Atlantic Ocean, the Mediterranean coast of Europe, and the Aegean, Marmora, Black, and Azov Seas. The latter is found in the Cape Blank region of the Atlantic Ocean and, probably, along the northwestern part of the African coast. The Aegean anchovy consists of hybrid populations, resulting from introgressive hybridization between the European and the African populations. No evidence for subspecies differentiation between the populations from the European coast of the Mediterranean and the Atlantic Ocean was found. Genetic distances between the Azov and Black Sea populations show that the former probably entered the Black Sea during the Karangad period and the latter during the last connection of the Black Sea to the Mediterranean. The genetic distance between the Black Sea anchovy and the Azov anchovy shows that they could be specified as two different populations. Probably some earlier subspecies differences disappeared as a result of introgressive hybridization.