Siniperca chuatsi, the mandarin fish or Chinese perch, is species of freshwater ray-finned fish from the family Sinipercidae, the Asian perches. Description Siniperca chautsi has a body that is compressed with a protruding lower jaw and the maxilla reaching behind the eyes. The jaws are armed with rows of saw-like teeth. Lower jaw with 4–5 large sharp rays. There are two flat, sharp spines on the posterior margin of the operculum. It has small, round scales. It has a shiny brownish-yellow body marked with randomly situated colored blotches and spots. They usually have black or dark grey stripes which run from their lips and run through the eyes over the lateral line but do not reach the back. It has a dorsal fin with the front part containing many hard spines with the rearmost having rounded tips. They have rounded pectoral, anal and caudal fins. There are three sharp spines situated in front of both pelvic and anal fins. The maximum recorded total length of 70 centimetres (28 in) and a maximum published weight of 8 kilograms (18 lb). Distribution Sinipercua cuatsi is found in the drainage basin of the Amur River (Russia/China) and in lowland freshwater habitats throughout East China and into Vietnam. Habitat and biology Siniperca chuatsi are found in rivers that have dense growths of aquatic vegetation and water which can be quite turbid in the rainy season. They are demersal piscivores, stalking the fry of other fish species using their acute vision to track their prey before pouncing on them and enveloping them in their large mouth. The species of fish it mostly preys on are diurnal and have good color vision and high visual acuity in daylight but which have poor night vision. Although it can live in near-freezing water, it only starts feeding when the temperature rises above 15 °C (59 °F) and breeding when it rises above 21 °C (70 °F).
