Length-weight relationship and condition factor of the Celebes rainbowfish Marosatherina ladigesi, endemic to the Maros karst region, South Sulawesi, Indonesia

Locally called beseng-beseng, Marosatherina ladigesi (Ahl 1936) is a rainbowfish endemic to the Maros karst region in South Sulawesi, Indonesia. The colorful > ladigesi male has become popular within ornamental fish hobbyists worldwide. However there is a lack of published information on the basic biological parameters of this species. This research aimed to determine the length-weight relationship and condition factors of two wild M. ladigesi populations. Sampling was carried out in two studies. In the first study, samples were collected 12 times at fortnightly intervals from October 2013 to March 2014. The fish were caught using a rectangular net (3 x 1m), 0.5 cm mesh size, from Bantimurung River (N = 338) and Pattunuang River (N = 331), both in Maros District. The samples were examined in the Fisheries Biology Laboratory, Hasanuddin University. The fish collected from Bantimurung river comprised 69 males and 269 females, while those from Pattunuang River comprised 88 males and 243 females. In the second study, samples were collected 8 times from July to October 2020. The number of samples obtained from the Bantimurung River was 206 individuals, while in the Pattunuang River no fish samples were obtained. The growth pattern of both male and female M. ladigesi from both rivers was isometric. In both populations the female M. ladigesi tended to have a higher condition factor than male individuals. In the second study, the growth type of M. ladigesi was hypoallometric.