Endang Yuli Herawati, Akhsan Fikrillah Paricahya, Ekwan Nofa Wiratno, Pratama Diffi Samuel, Chandika Lestariaji, Rahmi Valina, Alfi Nur Rusydi, Ruly Isfatul Khasanah
The study of aquatic environments can be conducted through the organisms that inhabit them, one of which involves a population genetics approach. Population genetics has been widely applied to various taxa, including fish; however, this approach remains very limited for keting catfish (Mystus gulio), especially in Pasuruan. Previous research has examined the environment and morphology of M. gulio in three Pasuruan rivers—Rejoso, Welang, and Gembong—but no population genetics study of M. gulio in Pasuruan and the surrounding areas has been conducted. Genetic analysis using the mitochondrial DNA (mtDNA) region of cytochrome oxidase subunit I (COI) can support molecular identification, as well as the estimation of genetic diversity and population structure. Sampling was carried out in three rivers in Pasuruan; the fish were preserved, and DNA extraction was performed up to the sequencing stage. Sequencing results were analyzed using BLAST identification, haplotype network analysis, phylogenetic trees, genetic p-distances, and pairwise Fst. The genetic diversity of M. gulio in each river in Pasuruan was low, with a nucleotide diversity (Pi) value of 0.00068 and a haplotype diversity (Hd) value of 0.400. Misidentifications in GenBank based on BLAST results for the Cilacap population were corrected using the haplotype network and phylogenetic tree generated in this study. The populations from each river are likely still connected, including those in Cilacap, as indicated by an Fst value of 0. It is possible that M. gulio migrates via the sea, as suggested by the low genetic distance (1.7%) between the Indonesian and Indian populations. Several overlaps were observed, which may represent a taxonomic conundrum. © 2025, Egyptian Society for the Development of Fisheries and Human Health. All rights reserved.
Faculty of Fisheries and Marine Sciences, Brawijaya University, Jl. Veteran, East Java, Malang, 65145, Indonesia; Department of Biology, Faculty of Mathematics and Natural Sciences, Brawijaya University., Jl. Veteran, East Java, Malang, 65145, Indonesia; Polytechnic of Marine and Fisheries Sorong, Southwest Papua, Indonesia; Aquaculture Study Program, Bangka Belitung University, Bangka, 33172, Indonesia; Marine Science Program, Faculty of Science and Technology, State Islamic University of Sunan Ampel, East Java, Surabaya, 60237, Indonesia
