<![CDATA[The sailfin catfish (Pterygoplichthys sp.) is an invasive species that has rapidly proliferated in Lake Sidenreng and poses ecological threats through food competition, habitat degradation, and disruption of native fish communities. This study aims to analyze the morphometric, meristic, and growth characteristics of sailfin catfish as a basis for understanding its biological traits and for developing management strategies to control its invasive population in Lake Sidenreng. The research was conducted from January to March 2025 using a quantitative descriptive method with a total sample of 400 individuals, all of which were used for the length–weight relationship analysis. From this total sample, 100 individuals were randomly selected for morphometric measurements (24 body characters) and meristic observations (counts of dorsal, pectoral, pelvic, anal, and caudal fin rays). The results showed an average total length of 30.09 cm (range 15.7–39.4 cm), with relatively narrow meristic variation, indicating population homogeneity. The length–weight analysis revealed negative allometric growth for both sexes. Males exhibited a low R² value (0.2134), indicating high variability in body weight associated with territorial behavior, whereas females showed a high R² value (0.8955), reflecting a more stable and controlled growth pattern. These findings highlight the strong adaptive capacity of Pterygoplichthys and its potential for population expansion in Lake Sidenreng, underscoring the need for effective management strategies to mitigate its ecological impacts.]]>
