Genetic diversity analysis and phylogeography of Osteochilus spilurus (Cyprinidae: Labeoninae) from Bangka, Belitung, and Kalimantan Islands (Indonesia) using Cytochrome b gene

The Sundaland fish species, Osteochilus spilurus is only utilized commercially in the Belitung Islands and has yet to be domesticated. This species can characterize freshwater fish phylogeography because have a minimum of human influence. This study aimed to analyze the genetic diversity and phylogeography of O. spilurus from the Bangka, Belitung, and Kalimantan Islands using Cytochrome b gene. Twenty fish samples were collected from the Sebangau and Kapuas Rivers in Kalimantan, the Lenggang River in Belitung Island, and the Lebak River in Bangka Island. Forward LA-cyp and reverse HA-cyp primers were used for amplification Cytochrome b gene. Mega 10.0 applications were used to construct of the phylogenetic tree. The phylogeographic analysis uses a comparative phylogenetic tree approach with geographical history. The cytochrome b gene showed variations in the nucleotides of O. spilurus from the three islands. Phylogeography of O. spilurus showed that there are two different clades with intraspecific variation according to a geographic area with bootstrap values of 99-100%. One clade contains fish samples from Bangka and Belitung islands, while the other clade comes from Kalimantan island. The formation of the Karimata Strait (between Bangka-Belitung and Kalimantan Islands) and the pattern of paleo rivers are predicted to influence the disparity.