Genetic structure of locally threatened cyprinid, Osteochilus melanopleurus, in Peninsular Malaysia River systems inferred from mitochondrial DNA control region

• Cyprinid species locally threatened in number, in which conservation measures need to be implemented.
• Case specific of anthropogenic activities such as dam and overharvesting is crucial evidence on the threatened species.
• Solution for ecological impact is through molecular approaches to investigate the current status of the targeted species on its genetic diversity.

The genetic structure of the locally threatened cyprinid Osteochilus melanopleurus, collected from four locations (Gerik, Manong, Bernam and Kahang) in Peninsular Malaysia River systems, was assessed based on partial sequences of the control region (D-loop) mitochondrial DNA. A partial D-loop of 364 base pair gene was extracted from 88 individuals through PCR amplification and direct sequencing. The results show that haplotype diversity (hd = 0.7956–0.9485) was high, with low nucleotide (π = 0.0045–0.0080) variation for each of the populations examined. A molecular variance analysis (AMOVA) revealed few differences between the four populations. A Tajima D test and Fu Fs test were used to investigate the neutrality of each population, revealing that the all examined populations might experience recent population expansion or the bottleneck effect. A phylogeny tree and mismatch distribution analysis provided further evidence that three of four populations had recently expanded, as well as indicating that the Kahang population had in contrast remained stable. Overall, this study concludes that the populations of O. melanopleurus distributed throughout the river systems of Peninsular Malaysia probably originated from a single ancestral source during the last glaciation period, and should therefore be treated as a single evolutionary unit in any conservation efforts.