
The goldfish (Carassius auratus) is a freshwater fish in the family Cyprinidae of order Cypriniformes. It is commonly kept as a pet in indoor aquariums, and is one of the most popular aquarium fish. Native to East Asia, the goldfish is a relatively small member of the carp family (which also includes the Prussian carp and the crucian carp). It was first selectively bred for color in ancient China more than 1,000 years ago, and several distinct breeds have since been developed. Goldfish breeds vary greatly in size, body shape, fin configuration, and coloration (various combinations of white, yellow, orange, red, brown, and black are known). == History == Various species of carp (collectively known as Asian carp) have been bred and reared as food fish for thousands of years in East Asia. Some of these normally gray or silver species have a tendency to produce red, orange or yellow color mutations; this was first recorded in ancient China, during the Jin dynasty (AD 265–420).During the Tang dynasty (AD 618–907), it was popular to raise carp in ornamental ponds and water gardens. A natural genetic mutation produced gold (actually yellowish orange) rather than silver coloration. People began to selectively breed the gold variety instead of the silver variety, keeping them in ponds or other bodies of water. On special occasions at which guests were expected, they would be moved to a much smaller container for display.By the Song dynasty (AD 960–1279), the selective domestic breeding of goldfish was firmly established.