Diversity, distribution, and conservation status of Betta fish (Teleostei: Osphronemidae) in Aceh waters, Indonesia

The Betta broodfish supply in Indonesia majorly comes from wild populations and fetches a higher price compared to hatchery cross-breeds, especially Betta rubra. This condition exerts pressure on the wild populations. Therefore, this study aims to examine the diversity, distribution, and conservation status of Betta fish species list in the study area. A total of 422 Betta fishes were collected from January 2019 to January 2021 from 19 of 59 sampling locations surveyed, consisting of four species, namely, Betta imbellis (TL: 14.09-31.98 mm; BW: 0.03-0.39 g), B. splendens (TL: 21.09-40.14 mm; BW: 0.05-0.70 g), B. rubra (TL: 11.35 to 47.80 mm; BW: 0.02-0.90 g), and B. dennisyongi (TL: 20.09-47.81 mm; BW: 0.07-0.91 g). There are four Betta species occurred in Aceh waters, namely B. dennisyongi, B. rubra, B. splendens, and B. imbellis. The results showed that B. dennisyongi was found at 8 sampling locations and had higher local distribution (13.56% LD) followed by B. rubra (8.47% LD), B. splendens (6.78% LD) and B. imbellis which had the lowest distribution and was only found in two locations (3.39% LD). Furthermore, field measurements (in situ) of water quality in the wild habitat showed temperature ranging from 23.7 to 31.9 degrees C while pH ranged from 5.24 to 8.51. Based on the IUCN Redlist data, B. rubra is categorized as being critically endangered.