摘要：AbstractUnambiguous and precise identifications of a species are crucial for managing and conserving the species across their dispersal regions. This study analyzed the molecular signatures and phylogenetic relationship of 84 specimens of lutjanids obtained from Malaysia, which covers three marine regions; Straits of Malacca (SM), west South China Sea (west SCS), and east South China Sea (east SCS). The assessment of 613 bp mtDNA COI has markedly classified the samples into five distinct species namelyLutjanus malabaricus,L. argentimaculatus,L. erythtropterus, L. sebaeandL. bohar. The intraspecific and interspecific genetic distance ranged between 0.1% − 0.7% and 8.2% − 19.6%, respectively. While genetic homogeneity occurred among population and species across SM and west SCS, significant genetic structuring was detected among species between west and east SCS as evidenced by the occurrence of a single species,L.boharthat can be found only in Sabah (east SCS). The divulged potential loss of gene flow among the regions and was probably caused by oceanic currents. This study detected an ambiguous sequence (from Genbank) probably due to hybridization between species or simply because of an unidentified node. This study proposed that COI is the valid and reliable genetic marker for identifying lutjanids distributed across Malaysian waters. Future revision in distribution pattern and diversity exploration on a large scale with a higher number of samples and different genetic markers is needed to fill this current study's gaps.
