Abstract:Tooth is an important feeding organ of carnivorous fish. The distribution, morphology and number of teeth in Siniperca chuatsi were observed s, and compared with S. kneri, S. scherzeri, Coreoperca whiteheadi. The dental structure, element composition and chemical composition of S. chuatsi were further studied with alizarin red staining, tissue sections, scanning electron microscopy, as well as X-ray energy spectrum (Mean ± SD) and infrared spectrum analyses. The results showed that S. chuatsi had maxillary teeth, mandibular teeth, vomerine teeth, palatal teeth and pharyngeal teeth (Fig. 1a﹣e). Among them, canine teeth were detected in front of maxillary teeth and the inner line of mandibular teeth, while the rest were villous teeth (Fig. 1a, b). The teeth of the vomerine, the palate and the pharynx were all villous (Fig. 1c﹣e). There were 3 rows in mandibular teeth in S. chuatsi and S. kneri, while 4 rows in S. scherzeri and C. whiteheadi (Table 1, 2). Alizarin red staining showed that the outer layer of canine and villous teeth was transparent enamel, and the inner layer was dentin containing pulp cavity (Fig. 3a, b). Histological sections showed that the dentin had loose structure and many pores, the tip of the tooth formed the enamel cap; the center was the pulp cavity, which contained pulp tissue (Fig. 4a﹣c). Scanning electron microscopy showed that the surface of canine and villous teeth was composed of enamel prisms, and the enamel layer had transverse stripes of enamel prisms (Fig. 5a, b). X-ray energy spectrum analysis showed that the main elements of canine and villous teeth were carbon, oxygen, nitrogen, calcium, phosphorus (Table 3). Infrared spectrum analysis showed that the main component of canine and villous teeth was carbonated hydroxyapatite (Fig. 6a, b). The results show that S. chuatsi has more advanced teeth with canines in maxillary and mandibular teeth, and the structure and composition of canines and villous teeth are basically similar.