Species identification and molecular analysis of terubuk fish from Bengkalis strait (Riau, Indonesia) using COI mitochondrial gene as a barcoding marker

Terubuk fish (Tenualosa spp.) commonly found in Bengkalis Strait is an important fishery commodity with a high economic value. However, the exploitation of the fish especially during spawning and hatching time due to the demand of the fish for consumption affects the decrease in numbers of the fish in Bengkalis Strait every year. Therefore, research on species identification and molecular analysis of the terubuk fish have to be investigated due to no genetic information can be used to make regulations and policies related to fish conservation. This research aimed to identify and examine the genetic polymorphism of terubuk fish in Bengkalis Strait using the partial COI mitochondrial gene. The method applied in this research was a PCR with primer FishF2 and FishR2. Genetic identification of the terubuk fish was analysed using nucleotide BLAST and Identification Engine through BOLD and genetic variation was evaluated using the DnaSP program. Genetic distance was examined using Kimura 2 parameter (K2P) model. The phylogenetic tree was constructed using Bayesian Inference through the BEAST program. The result revealed that all samples of terubuk fish were identified as Tenualosa macrura. The terubuk samples investigated in this study have 4 haplotypes with 6 variable sites dan 1 parsimony site. The haplotype diversity and nucleotide diversity were 0.714 and 0.00353 respectively with a genetic distance of 0-0.9% (mean= 0.4%). This finding is first reported and the genetic information gained in this study is expected to be implemented for terubuk fish conservation, especially in Bengkalis Strait.