Length–Weight Relationships of Four Fish Species Belonging to the Genus Traccatichthys (Teleostei: Nemacheilidae) in Southern China

Traccatichthys is a genus of small benthic omnivorous nemacheiline loaches, with limited ecological and biological data available. Here, we described length–weight relationships (LWRs) for four Traccatichthys species from southern China. Fishes were sampled using stationary fish cages (10 m in length, mesh size: 0.5 cm) between January and April 2025 at four selected sampling sites. All specimens were transported to the laboratory within 2 days of collection, maintained alive in oxygenated water, and measured for total length (TL) to the nearest 0.1 cm and body weight (BW) to the nearest 0.01 g in the laboratory. LWRs were calculated using linear regression, and the four species‐specific models were all highly significant ( p < 0.001). The allometric exponent b values ranged from 2.875 to 3.196. The LWRs for three species ( T. tuberculum , T. zispi , and T. taeniatus ) are new to FishBase (as of May 2025). Our results provide essential baseline data for sustainable management and ecological research of these species.