Conservation status: IUCN – LC (Least concern).
Geographic range: Japan.
Physical description: This species is characterized by its colours and markings. Currently, 24 different variations of Koi are known to differ from one another by colour, markings and even scales. Most common colours are white, black, red, orange, yellow, blue and crème. These fish can weigh up to 16 kilograms.
Biology: These carps were primarily bred for human food, however nowadays they are also valued for their beauty. People started breeding these fish for their colourations, starting more than one thousand years ago. Koi carps prefer cold waters, but they can adapt to various conditions. The best age range for breeding Koi is between 3 and 6 years old. The most expensive Koi ever sold cost 2,2 million USD. The oldest known carp was named Hanako and lived for 226 years.
Lifespan: 20 – 40 years.
Food habits: Omnivorous.