Abstract
The present paper is based on the literature review and the recent information about the distribution range of the alien brown shrimp Penaeus aztecus Ives, 1891 in the Mediterranean Sea. This alien species has spread throughout the Mediterranean Sea (especially the eastern part) mainly through ship/ballast water introductions and has presently been reported by eight countries (27 localities). Introduction pathways and chronological distribution patterns of the alien brown shrimp species are discussed. Penaeus aztecus forms dense populations along the coast of the Turkish Mediterranean Sea, and it has a potential for colonising the native habitats of autochthonous species.