Similarity and Genetic Variation of Climbing Perch, <i>Anabas testudineus</i> (Bloch, 1792), From Java, Sumatra, and Kalimantan Islands, Indonesia

Climbing perch, <i>Anabas testudineus</i>, is an economically important freshwater fish in Indonesia. The climbing perch, also known as betok, has emerged as a prominent species in aquaculture due to its air-breathing ability, which allows the climbing perch to thrive in low dissolved oxygen environments. However, there is a lack of information on the genetic diversity of climbing perch from potential sources of populations as candidates for sustainable culture development. This study aimed to analyze the similarity, genetic distance, and diversity of climbing perch from Java, Sumatra, and Kalimantan Islands. We examined 21 truss morphometric characters to determine the intrapopulation variation. In addition, to assess genetic diversity and phylogenetic relationship between populations of climbing perch, we used random amplified polymorphic DNA (RAPD) with primers OPA 07, OPC 02, and OPC 05. The result showed that the population of climbing perch from Kalimantan shows higher similarity with the population from Sumatera (49.97%) than the population from Java (24.96%). Climbing perch from Kalimantan showed the highest polymorphism and heterozygosity of 39.29% and 0.16%, respectively. The interpopulation genetic distance between Kalimantan, Sumatera, and Java ranged from 0.17 to 0.39. The result suggests that the climbing perch from Kalimantan has potential as a candidate for the culture development of the climbing perch.