Analysis of Population Genetics of the Endangered Nile Pufferfish Tetraodon lineatus (Linnaeus, 1758) in the Upper Egyptian River Nile

Abstract

Genetic population analyses for Nile fishes are very scarce. Nile pufferfish Tetraodon lineatus (Linnaeus, 1758), is a widely-distributed freshwater fish, with no known major widespread threats. It has been classed as 'Endangered'. Little is known concerning its biology and genetics in Egypt. Hence, this work was designed to study the genetic diversity and conservation status of T. lineatus for the first time in Egypt and Africa. DNA barcoding was carried out through PCR-amplification and sequencing of the cytochrome c oxidase gene barcode 5´ region of forty-five samples obtained from three different localities in Upper Egypt. Only three haplotypes could be characterized in all samples. The other population analyses showed clear population loss of extension and potential bottleneck, what may explain the severe drop of species records in the Northern areas of the Nile. Phylogenetic analysis exhibited the monophyletic origin T. lineatus and other African freshwater pufferfishes, more probably as descendants from an Indo-West Pacific ancestor. We highly recommend the fulfilling of more studies concerning the biology, ecology, and genetics of the species as major steps towards its proper conservation and understanding of its adaptation to different natural and man-made constraints in the River Nile system.