DNA Barcoding of Endangered Giant Freshwater Whipray Urogymnus polylepis (Bleeker, 1852) from North Kalimantan, Indonesia

Stingrays are a subset of Elasmobranchii, a group of fish species that are characterized by their cartilage-based skeletal systems. Within Indonesia, stingrays have consistently held a position of economic significance, particularly for their high export value. However, the combined pressures of over-exploitation and insufficient conservation initiatives have threatened stingray populations in various Indonesian waters. To aid conservation efforts, it's crucial to precisely identify stingray species. This not only helps in establishing their conservation status but also in preserving the genetic integrity of both the species and their ecosystems. While several methods exist for fish identification, DNA barcoding stands out as a revolutionary molecular-based technique offering swift, accurate, and definitive organism identification. This research aimed to identify the species of stingrays found in the Sesayap River of North Kalimantan Indonesia and delineate the relationships among these species using phylogenetic trees. To construct the phylogenetic tree, we employed the MEGA11 software, utilizing the neighbor-joining algorithm and the Kimura-2 parameter model with a bootstrap value set at 1000. Our findings identified a single stingray species, Urogymnus polylepis. The phylogenetic analysis indicates that this species shares a close genetic relationship with a genetic distance of 0.000-0.002 to the U. polylepis found in Thailand. Notably, the conservation status of the U. polylepis is currently listed as "Endangered (EN)".