Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4
A koi fish, named "Hanako", was owned by several individuals over many years and lived to be 226 years old, dying in 1977.
6
There is a disease called ichthyosis that turns the skin scaly like a fish.
90
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
Sharks, like other fish, have their reproductive organs in their chests.
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