Abstract: During the period from 2006 to 2009, the spawning fields of Diptychus maculates and Gymnodiptychus dybowskii in the Kunes River were investigated, their ecological and environmental factors including the geographical location, flow velocity, water depth, bottom material and water temperature were studied in detail, and the suitability curves of the two fish species were proposed. The results showed that there were the distinct differences in the ecological and environmental factors between the spawning fields of these two fish species. The spawning fields of D. maculatus were located at the upper reaches of the river, where the breeding temperature was 2-7 ℃, bottom material was cobble stone with a diameter of 15-80 cm, water depth for breeding was 20-60 cm, and water velocity was 0.3-1.0 m•s-¹; while the spawning fields of G. dybowskii were located at the middle reaches, where the breeding temperature was 8-14 ℃, bottom material was gravel with a diameter of 5-30 cm, water depth for breeding was 10-80 cm, and water velocity was 0.2-0.6 m•s^-1.

Key words: Gymnodiptychus dybowskii, Diptychus maculates, spawning field, micro-environment, suitability, Kunes River, Xinjiang