Swallowtail fish is a kind of fish in Lake Tanganyika, Africa. Swallowtail fish is 8~ 10 cm long and light brown. The tail fin end is longer and sharper than the white-edged swallowtail fish, with a black line erected behind the gill cover and a light blue pattern on the face. There is no obvious difference between female fish and male fish. From the appearance, the fins of male fish are bigger and sharper than those of female fish, and the abdomen of female fish will swell during the breeding period. The culture water temperature is 27~28℃.