Uncovering the genetic structure and evolutionary history of (Actinopterygii, Sparidae) using mitochondrial DNA and multivariate analyses: A case study of coastal populations in Central Vietnam.

The yellowfin seabream (), a commercially important marine fish in Vietnam, faces threats from overfishing and habitat degradation and requires a deeper understanding of its genetic structure and evolutionary history for effective conservation. This study investigated the genetic diversity, population structure and demographic history of across three populations in Central Vietnam using mitochondrial control region (mtCR) sequences and multivariate analyses. A total of 125 fish samples were collected between January 2023 and June 2024, with DNA extracted from pectoral fin tissues and amplified for mtCR sequencing. Phylogenetic and haplotype network analyses revealed three main haplogroups with high genetic diversity (haplotype diversity: 0.993 ± 0.002), but minimal population differentiation (Fst = 0.00029, p = 0.39188), indicating significant gene flow, facilitated by coastal currents as these populations maintain strong genetic connectivity with the coastal populations of southern China. Neutrality tests, mismatch distribution and Bayesian Skyline Plots have suggested a historical population expansion followed by recent stability and slight decline. These findings highlight the species' resilience, but underscore the need for regionally coordinated conservation strategies to protect critical habitats like estuaries and mangroves, ensuring the sustainability of populations in Vietnam.