BIODIVERSITAS ISSN: 1412-033X Volume 22, Number 2, February 2021 E-ISSN: 2085-4722 Pages: 794-802 DOI: 10.13057/biodiv/d220233 First genetic record and the phylogenetic relationship of Osteochilus spilurus (Cyprinidae: Labeoninae ) originating from Bangka and Belitung Islands, Indonesia ARDIANSYAH KURNIAWAN 1,2, , ANIK M. HARIATI 3 , ANDI KURNIAWAN 3 , DEWA G.R. WIADNYA 3 1 Doctoral Program, Faculty of Fisheries and Marine Science, Universitas Brawijaya. Jl. Veteran, Malang 65145, East Java, Indonesia. Tel.: +62-341-553512, Fax.: +62-341-557837,  email: ardian_turen@yahoo.co.id/ardikurniawan@student.ub.ac.id 2 Department of Aquaculture, Faculty of Fisheries, Agriculture and Biology, Universitas Bangka Belitung. Jl. Kampus Peradaban Balunijuk, Merawang Bangka 33172, Bangka Belitung Islands, Indonesia 3 Faculty of Fisheries and Marine Science, Universitas Brawijaya. Jl. Veteran, Malang 65145, East Java, Indonesia. Tel.: +62-341-553512, Fax.: +62-341-557837,  email: dgr_wiadnya@ub.ac.id Manuscript received: 30 November 2020. Revision accepted: 16 January 2021. Abstract. Kurniawan A, Hariati AM, Kurniawan A, Wiadnya DGR. 2021. First genetic record and the phylogenetic relationship of Osteochilus spilurus (Cyprinidae: Labeoninae) originating from Bangka and Belitung Islands, Indonesia. Biodiversitas 22: 794-802. Osteochilus spilurus is a freshwater fish from Southeast Asia. Species identification for this fish in Indonesia is still solely limited to morphological characteristics. Therefore it is highly important to validate using short DNA sequences that have been proven to be fast, effective, and accurate. Fish specimens were collected from Lenggang river in Belitung island, and Lebak river in Bangka island, Indonesia. Mitochondrial cytochrome b gene (cyt b, 408 bp) was amplified and sequenced. We collected fish specimens from Lenggang River in Belitung Island and Lebak River in Bangka Island, Indonesia. The results suggested that individuals from both islands are clustered together with a strong bootstrap value (100%) in a monophyletic clade. The specimens deposited at NCBI as the first Indonesian genetic records. They have a sister lineage to individuals from Sabah, Malaysia, although supported by a low bootstrap value. While geographical connection during the Pleistocene period allowed wide distribution of the species, differences in the evolutionary processes of historical biogeography and environmental changes are the predicted cause of the low genetic similarity. These findings can be used as a sequence reference and basic information for conservation of this species. Keywords: Cytochrome b, mtDNA, Osteochilus, Sundaland INTRODUCTION Osteochilus spilurus is native freshwater fish in Indonesia, widely distributed in Southeast Asia. Previous studies have shown that geographic distribution of this species is Sundaland, including in Thailand, Malay Peninsula, Borneo, and Sumatra Island (Kottelat et al. 1993; Fahmi et al. 2015; Haryono and Wahyudewantoro 2020; Lumbantobing and Huckstorf 2020). They are usually found in acidic water of low-velocity rivers. The fish marked black blotch at the base of the tail and has a length of not more than 10 cm are benthopelagic (live between the surface and deep water areas). They also like to move in groups with other small fish and are positioned at the bottom of the group. There are no publications that specifically discuss O. spilurus apart from Bangka and Belitung Islands. Most of the publications indicate the existence of this species as an ichthyofauna in the freshwater river. Osteochilus spilurus is not a common fish in Indonesia. They have not got a national tag. For this species, each island has a local name. They are Toros in Malaysia, Seluang Licin in Central Borneo, Seluang Sungai in southern Sumatra, Kepait in Bangka island, and Cempedik in Belitung island (Huckstorf 2012; Muslih et al. 2014; Fakhrurrozi et al. 2016; Kurniawan et al. 2020a). This fish is known by almost all Belitung people but is only known by anglers on other islands. Belitung community likes to consume this slightly bitter-tasting fish as a protein source (Kurniawan et al. 2016). Even these fish are included in society's culture with the emergence of ethnic songs and Batik with the theme of Cempedik. The economic value of O. spilurus has increased due to demand and habit of Belitung residents to consume it, especially in East Belitung (Kurniawan and Triswiyana 2019). This fish, which was the least concern, now needs serious attention due to the exploitation of nature and its trade. Consumption of fish relying on the natural catch can pressure its natural population. Pragmatically, fish domestication will reduce the burden on the natural ecosystem through fishing while satisfying consumer demand. Kurniawan et al. (2019) have started the first level domesticated as aquaculture commodities, and related aspects of fish domestication are studied in more detail by Radona et al. (2020). At present, O. spilurus is in the first stage of domestication. Fish have been able to live in artificial containers on this level. Treatment of running water is a critical finding in the domestic process (Kurniawan et al. 2019). Stress and fish mortality decreased when the water in the container flowed even