A Florida man walked into a convenience store with a four-foot alligator and tried to trade it for a 12-pack of beer, according to wildlife authorities who cited him with illegally taking the animal from a park.

"That crazy guy, he came to the store with a small alligator. He tried to sell it to buy a couple of beers," said Javier Herrera, the store owner.

It was unclear why the man thought the clerk at the Santa Ana Market in Miami would accept the reptile as payment.

Mr Herrera said he was concerned that the wild animal might get lose and bite one of his customers, so he asked the man to leave, but he would not.

"I was scared. It's the first time that I see somebody with that kind of animal in the store," he said.

Mr Herrera said that one of the customers called authorities.

Suspect Fernando Caignet Aguilera was reportedly arrested and charged with possessing, illegally taking and attempting to sell an alligator.

"He was standing over there with the alligator. After that, five minutes later, the police came here to arrest him because somebody called 911," said Mr Herrera.

Each of the three misdemeanour charges carries a penalty of up to six months in jail and a fine up to $500, according to wildlife authorities.

The alligator was unharmed and was released back into the wild.