Unlike modern sushi, which typically includes ocean seafood, Narezushi was made – and still is in small pockets of Japan – with pretty much anything that swims in fresh water, including tiny loach, ayu (small sweet fish) and eel. But the kind of narezushi Kitashina makes is much rarer and is considered the true prototype of sushi. It is called funazushi after the type of fish used: funa (carp).