Length–weight relations of 14 endemic and indigenous freshwater fish species (Actinopterygii) from the Aral Sea basin, Uzbekistan

Abstract

Length–weight relations (LWR) were estimated for 14 endemic and indigenous fish species from the Aral Sea basin: Alburnoides holciki Coad et Bogutskaya, 2012; Capoetobrama kuschakewitschi (Kessler, 1872); Cottus spinulosus Kessler, 1872; Glyptosternon oschanini (Herzenstein, 1889); Gobio lepidolaemus Kessler, 1872; Gobio nigrescens (Keyserling, 1861); Iskandaria kuschakewitschi (Herzenstein, 1890); Iskandaria pardalis (Turdakov, 1941); Paracobitis longicauda (Kessler, 1872); Sabanejewia aralensis (Kessler, 1877); Schizothorax fedtschenkoi Kessler, 1872; Triplophysa daryoae Sheraliev, Kayumova et Peng, 2022; Triplophysa ferganaensis Sheraliev et Peng, 2021; and Triplophysa uranoscopus (Kessler, 1872). Measurements were taken for total length (0.1 cm precision) and total weight (0.1 g precision). The LWR parameters were determined using a linear logarithmic regression model of weight against length in which values for the slope of the regression, b, that are higher and lower than 3 indicate positive and negative allometric growth, respectively. The estimated values of parameter b ranged from 2.703 (Iskandaria kuschakewitschi) to 3.162 (Gobio nigrescens). The correlation coefficient (r2) values varied from 0.951 to 0.993, indicating a strong positive relation between length and weight. The maximum total lengths of four of the species (Glyptosternon oschanini, Iskandaria kuschakewitschi, Triplophysa daryoae, and Triplophysa uranoscopus) constitute new records, and the LWRs of twelve fish species have hitherto not been available in FishBase.