Koi , or Nishikigoi, are ornamental varieties of domesticated common Carp (Cyprinus carpio) that are kept for decorative purposes in outdoor koi ponds or water gardens. Koi were originally used as a source of food by rice farmers in China. However, as the fish made their way to Japan, the Japanese soon admired the amazing colors of koi fish. They started breeding different varieties and spectacular colors and patterns were achieved. The koi fish hobby was born.
Koi varieties are distinguished by coloration, patterning and scalation.
Colors are primarily white, black, red, yellow, blue and cream.
The most popular category of Koi is the Gosanke, which is made up of the Kohaku, Taisho Sanshoku, and Showa Sanshoku varieties.
Varieties are distinguished by coloration, patterning and scalation. The most popular category is Gosanke, which is made up of the Kohaku, Taisho Sanshoku, and Showa Sanshoku varieties.
(紅白) KOHAKU is a white-skinned koi, with large red markings on the top. The name means "red and white"; kohaku was the first ornamental variety to be established in Japan (late 19th century).
Asagi (浅黄) koi is light blue above and usually red below, but also occasionally pale yellow or cream, generally below the lateral line and on the cheeks.
Bekko (べっ甲) is a white-, red-, or yellow-skinned koi with black markings sumi (墨). The Japanese name means "tortoise shell", and is commonly written as べっ甲. The white, red, and yellow varieties are called Shiro Bekko (白), Aka Bekko (赤) and Ki Bekko (黄), respectively. It may be confused with the Utsuri.
Goshiki (五色) is a dark koi with red (Kōhaku style) hi pattern. The Japanese name means "five colors". It appears similar to an Asagi, with little or no hi below the lateral line and a Kōhaku Hi pattern over reticulated (fishnet pattern) scales. The base color can range from nearly black to very pale, sky blue.
Ochiba (落葉) is a light blue/gray koi with copper, bronze, or yellow (Kohaku-style) pattern, reminiscent of autumn leaves on water. The Japanese name means "fallen leaves".
Taishō Sanshoku (or Taishō Sanke) (大正三色) is very similar to the kohaku, except for the addition of small black markings called sumi (墨). This variety was first exhibited in 1914 by the koi breeder Gonzo Hiroi, during the reign of the Taishō Emperor. In the United States, the name is often abbreviated to just "Sanke". The kanji, 三色, may be read as either sanshoku or as sanke (from its earlier name 三毛).
The Kujaku is a metallic or Ogon koi with the reticulated net-like pattern of the Matsuba on it's back. This is overlaid with either a gold, yellow, orange or red Kohaku-type pattern creating a stripe.
Hikari-moyomono (光模樣者) is a koi with colored markings over a metallic base or in two metallic colors.
Kawarimono (変わり物) is a "catch-all" term for koi that cannot be put into one of the other categories. This is a competition category, and many new varieties of koi compete in this one category. It is also known as kawarigoi (変わり鯉).
Koromo (衣) is a white fish with a Kohaku-style pattern with blue or black-edged scales only over the hi pattern. This variety first arose in the 1950s as a cross between a Kohaku and an Asagi.
The Showa classification implies a black (Sumi black) koi with red (Hi-meaning sharp red patches) and white (Shiro) markings. The Showa is created by crossing a Kohaku Koi with a Shiro Utsuri variety. First produced in 1927, the Showa Koi was named for the Showa Emperor, who was in power during time. Originally, there was a different proportion between red (Hi) and white (Shiro)markings on this type of Koi.
Tanchō (丹頂) is any koi with a solitary red patch on its head. The fish may be a Tanchō Shōwa, Tanchō Sanke, or even Tanchō Goshiki. It is named for the Japanese red-crowned crane (Grus japonensis), which also has a red spot on its head.
Kumonryū (九紋竜)' （literally "nine tattooed dragons" is a black doitsu-scaled fish with curling white markings. The patterns are thought to be reminiscent of Japanese ink paintings of dragons. They famously change color with the seasons.
Matsuba are koi that combine a solid, metallic colored base with a black net pattern. The base color of Matsuba can vary. Gin Matsuba have a white base color, while Ki Matsuba have a yellow base color, and Aka Matsuba have a red base. The sole variation of Matsuba is Doitsu Matsuba.
Tanchō (丹頂) is any koi with a solitary red patch on its head. The fish may be a Tanchō Shōwa, Tanchō Sanke, or even Tanchō Goshiki.
Utsurimono (写り物) is a black koi with white, red, or yellow markings, in a zebra color pattern. The oldest attested form is the yellow form, called "black and yellow markings" (黒黄斑 Kuro ki madara) in the 19th century, but renamed Ki Utsuri (黄写り) by Elizaburo Hoshino, an early 20th-century koi breeder. The red and white versions are called Hi Utsuri (緋写り) and Shiro Utsuri (白写り) (piebald color morph), respectively. The word utsuri means to print (the black markings are reminiscent of ink stains).
'Shūsui (秋翠) means "autumn green"; the Shūsui was created in 1910 by Yoshigoro Akiyama（秋山 吉五郎, by crossing Japanese Asagi with German mirror carp. The fish has no scales, except for a single line of large mirror scales dorsally, extending from head to tail. The most common type of Shūsui has a pale, sky-blue/gray color above the lateral line and red or orange (and very, very rarely bright yellow) below the lateral line and on the cheeks.
Ōgon (黄金) is a metallic koi of one color only (hikarimono 光者). The most commonly encountered colors are gold, platinum, and orange. Cream specimens are very rare. Ogon compete in the Kawarimono category and the Japanese name means "gold". The variety was created by Sawata Aoki in 1946 from wild carp he caught in 1921.
Butterfly koi originated in the mid-20th century as a result of an effort to increase the hardiness of traditional koi. Japanese breeders interbred wild Indonesian longfin river carp with traditional koi. The resulting fish had longer fins, long barbells, pompom nostrils, and were hardier than koi. These were known in Japan as "onagaoi" or "hire naga goi", or translated in English "long tail carp".
Kinginrin (金銀鱗) is a koi with metallic (glittering, metal-flake-appearing) scales. The name translates into English as "gold and silver scales"; it is often abbreviated to Ginrin. Ginrin versions of almost all other varieties of koi occur, and they are fashionable. Their sparkling, glittering scales contrast to the smooth, even, metallic skin and scales seen in the Ogon varieties. Recently, these characteristics have been combined to create the new ginrin Ogon varieties.
Kikokuryū (輝黒竜, literally "sparkle" or "glitter black dragon") is a metallic-skinned version of the Kumonryu.
Chagoi (茶鯉), "tea-colored", this koi can range in color from pale olive-drab green or brown to copper or bronze and more recently, darker, subdued orange shades. Famous for its docile, friendly personality and large size, it is considered a sign of good luck among koi keepers.
Ghost koi (人面魚、じんめんぎょ), a hybrid of Ogon and wild carp with metallic scales, is considered by some to be not nishikigoi.