5. Koi fish
Going back to the ocean, we have another example of the longest-living animals, and that is the koi fish. An ornamental, domesticated variety of the common carp, this fish species has an average lifespan of 40 years, though, according to the Smithsonian’s National Zoo, the oldest known koi lived to be more than 200.
What makes a koi fish live longer than any other fish species is apparently their genes, which are thought to be better. They are native to the fresh waters of the Caspian Sea and can grow up to three feet in length.
Wild populations can be found in Europe, Africa, Asia, North America, and South America. Koi are common in decorative ponds and artificial rock pools.
