Cuatsi is a polyphonic character that can be pronounced either jué or guì.

Cuatsi (scientific name: Siniperca chuatsi) is a fish in the family Serpulidae, genus Siniperca. The body is tall, laterally compressed, with a prominent dorsal bulge behind the eyes. The head is medium to large. The muzzle is pointed and protruding, and the muzzle is larger than the eye diameter. Eyes large, slightly larger than the interocular septum. Mouth large, terminal, obliquely cleft. With a supplementary maxilla. Posterior end of maxilla extends to or beyond below posterior margin of eye, mandible prominent. Both jaws, plow bones and palatine bones with choroidal tooth groups, several teeth enlarged or canine in anterior part of both jaws. Posterior margin of anterior gill cover bone serrulate, with 2 small spines on each lower corner and lower margin. Posterior margin of gill cover with 2 flat spines.

Life habits

Chiniperca chuatsi belongs to the completely freshwater life of the fish, like to inhabit in rivers, lakes, reservoirs and other aquatic plants in the cleaner water, usually lurking in the daytime underwater, night activities around for food. Do not like to make long-distance wandering and migration, do not like to live in groups. Living in the appropriate water temperature 15 ~ 32 ℃. However, some scholars have shown that within the range of 10～25℃, the specific growth rate of Siniperca chuatsi increases with the rise of temperature.

Between 25 and 35℃, there was no significant change, and when the water temperature of 35℃ was reached, the growth of Mandarin fish did not slow down significantly. This is inconsistent with the results of the general study on the relationship between fish and water temperature, i.e., within a certain range of temperatures, the feeding rate and growth rate of fish increase with the increase of water temperature, and when the water temperature exceeds the optimal water temperature, the feeding rate and growth rate of fish will instead decrease, which indicates that that the optimum growth temperature of Mandarin fish may be wider.