THE OCCURRENCE OF THE ATLANTIC PENAEID PRAWN FARFANTEPENAEUS AZTECUS (IVES, 1891) IN THE THERMAIKOS GULF (AEGEAN SEA, EASTERN MEDITERRANEAN): CONSIDERATIONS ON THE POTENTIAL ESTABLISHMENT AND IMPACT ON THE AUTOCHTHONOUS MELICERTUS KERATHURUS (FORSKAL, 1775)

The penaeid prawn Farfantepenaeus aztecus (Ives, 1891), of western Atlantic origin, has been recently recorded in a lagoonal environment in the Thermaikos Gulf (North Aegean Sea) increasing the number of alien decapods in the Aegean Sea to 29. The present work reports the finding of F. aztecus in offshore waters on the trawling ground of the Thermaikos Gulf. The presence of this alien species in the area is probably due to ships' ballast water or to expansion northward from the Levantine Sea where it was recently reported. The life cycle characteristics and several properties of the Atlantic species along with the abiotic and biotic factors of the Thermaikos indicate that the species will eventually be established successfully in the gulf. However, the potential establishment of F. aztecus in the Thermaikos Gulf raises concerns over the fate of the autochthonous penaeid prawn Melicertus kerathurus (Forskal, 1775) in the North Aegean Sea.