New Insights Into the Biogeography of Six Garra Species (Teleostei: Cyprinidae) in the Persian Gulf Basin

ABSTRACT Natural and anthropogenic changes have shaped the geographical distributions of freshwater fishes. During the Last Glacial Maximum (LGM), marine water retreated from the Persian Gulf, and it has been hypothesized that the Tigris River then received all tributary rivers of the present Persian Gulf and reached the Sea of Oman. In this study, we assess the extent and mechanisms of regional movements of the cyprinid freshwater fish Garra rufa and its interactions with a few surface‐dwelling and subterranean congeners in the studied region. We analyzed genome‐wide single nucleotide polymorphism (SNP) data and mitochondrial DNA sequences of fishes from the Tigris, Karkheh, Karun, Jarahi, Dalaki, and Mond rivers. It appears that after the LGM, colonization of G. rufa into the Mond and Dalaki drainages of the Persian Gulf, unidirectional movements of G. rufa from the Dalaki to the western drainages of the Persian Gulf and to the inland Maharlu lake basin may have occurred through river capture. Further, our results, along with published morphological data, indicate no genomic or morphologic differences between G. rufa and G. mondica as well as G. gymnothorax , questioning their status as own evolutionary units. Further, we also found signatures of introgression from G. rufa into G. tashanensis in the Jarahi drainage.