Genetic evidence for wide distribution of the alien prawn-goby, Vanderhorstia mertensi (Actinopterygii: Perciformes: Gobiidae), along the northeast Mediterranean

Vanderhorstia mertensi Klausewitz, 1974, is a recently acknowledged alien fish in the Mediterranean Sea, hitherto observed only from Fethiye Bay, Turkey. To explore its distribution, trawl bycatch from eastern Antalya and Iskenderun was examined and an underwater survey was performed off Kas (western Antalya). An established pop-ulation was found off Güvercin Island, Kas, and six specimens were identified from trawl bycatch collected off Antalya and Iskenderun. The trawl-collected specimens were badly damaged and identification was made possible by the analysis of their 16S rDNA sequences. Our findings suggest that the species was only recently introduced and its population size has increased rapidly. Symbiotic relationship with alpheids (Apheidae, Crustacea) may have enhanced this prawn-goby's establishment and dispersal along the Mediterranean coast of Turkey.