Genetic diversity of Hilsa kelee collected from the Bay of Bengal and the Arabian Sea

The Kelee shad (Hilsa kelee) is currently considered as the only representative species in the genus Hilsa (Clupeidae, Clupeiformes) with a wide distribution in almost all coasts of the Indian Ocean. Two marginal marine water bodies of the Indian Ocean, the Bay of Bengal and the Arabian Sea, are important fisheries areas for this fish. In this study, a comparison of genetic diversity of Kelee shad of these two important fisheries areas was conducted by applying a cross-species gene enrichment method. This was also the first challenge to discover the genetic diversity of this fish. Analysis of molecular variance results showed that the variation between groups is 10.85% and among individuals within populations contributed 89% variation. Nucleotide diversity results showed that Kelee shad populations are in almost stable condition and have a moderate population size. Nucleotide diversity of the Bay of Bengal and the Arabian Sea were almost similar; these were 0.012138 and 0.010831, respectively. Network, structure, and PCA results suggested that Kelee shad of the Bay of Bengal and the Arabian Sea have significant genetic differences. These two populations were separated from each other by a FST value of 0.10955 (p < 0.05). It is speculated that Southern India along with Sri Lanka and Ram bridge together with ancient climatic differences acted as means of isolation concerning Kelee shad populations between these two water bodies. Furthermore, from the maximum likelihood phylogenetic tree, it is established that the Arabian Sea can be regarded as the major stock of this species.