Hey, guys, if you go lake fishing in hip boots in New Jersey, you’d better wear a cup to protect the “family jewels.”

A man and his son caught a strange species in Swedes Lake in South Jersey that turned out to be a rare Amazonian fish known in South America as the “Nutcracker,” according to reports.

The pacu fish looks like a piranha but instead of razor teeth has flat, almost human choppers.

It’s notorious for biting the testicles of swimmers and fishermen in the Amazon, the Daily Mail said.

The Jersey pacu may have been in someone’s exotic aquarium ­before being abandoned.