The freshwater fish is a rare, endemic and economic species, only distributed in the middle and upper reaches of the Nujiang River (Upper Salween River) in China. Potential cascade hydropower development in the Nujiang River will threaten the survival of . The potential for drastic changes in the water flow, water temperature and food supply of their habitat may lead to extinction of . Therefore, biological research on future conservation and resource utilization is imperative. Herein, the histology and ultra-structure of the gill in the teleost was investigated using the optical and electron microscopic imaging techniques. The results showed that the basic structure of the gills consisted of the gill raker, gill arch, gill filament and lamellae, which was similar to other teleost fishes. Different parts of the gill possess distinct histological structures and cell types. The pavement cells (PVC) covered the filament epithelium and lamellae of the gills, showing three distinct morphological features of micro-ridges in the different parts of the gill. There was only one type of mitochondrial rich cells (MRC) observed in the gill, which were located at the base of lamellae. All these MRC have a large number of big, round mitochondria and exhibit apical shallow-basin with microvilli. Our results suggested that the morphological feature and functional diversity of PVC and MRC in the gill of were in accordance with its habitat. These observations enrich the basic biological knowledge of and can provide a reference for clarifying the relationship between the specific structural characteristics of the fish and their living habits.