Pop-eyed goldfish

The Popeyed Goldfish is a rare fish in the found in the river. It sells for 1,300 Bells in Tom Nook's Store and appears all year, during the hours of 9 AM to 4 PM. Its shadow size is tiny, and it not only diurnal, but it is rarer than the regular Goldfish. It is frequently one of the last fish to find in many player's games.

In City Folk
When accepting the fish for the Museum, Blathers will say: "Popeyed goldfish look like any other ordinary goldfish whilst still juveniles. As they begin to mature, their eyes bulge outward and gradually assume that distinctive appearance. Imagine how appalled you'd be if you brought one home thinking it was a normal goldfish...".

Wild World

 * Size: 5.9 inches
 * Habitat: Rivers
 * Season: All year
 * Though their eyes are big, their vision are poor.

City Folk

 * Size: About 5.9 inches
 * Habitat: Rivers
 * Season: All year

Further Information
The Carassius auratus shares its scientific name with all types of Goldfish, as this is the name of their direct ancestor, the Crucian Carp. The Popeyed Goldfish, or Black Moor Goldfish, is a harmless fish that lives in slow-flowing ponds, ditches, rivers, and lakes. It is a specially bred type of carp with large, protruding eyes, which to some peoples surprise has poor eyesight as a result of its heavy inbreeding. It is related to other types of telescope fish, Carp and is indirectly related to the Koi. It feeds off of small insects, crustaceans, and plants. In China, it is called the dragon-eye. The species name "auratus" refers to the slight golden shine on its scales.