The Izumo Nankin (出雲南金) is a rare breed of goldfish native to southwestern Japan.
It is very difficult to source individuals outside Japan, but Nankin are commonly available there.
[1] This breed has many fanciers in its native country, with many clubs dedicated to it such as the Central Nankin Lovers Association.
[2] The nankin is a top-view fish and typically comes in a red and white coloration.
[3] The body form resembles a dorsal-less ryukin goldfish with a ranchū-like tail.