FORT LAUDERDALE, Fla. — They met in a parking lot like a pair of drug dealers, but the contraband consisted of live piranhas.

An undercover wildlife officer bought three red-bellied piranhas in West Palm Beach, Fla., last week, in an operation aimed at keeping the ferocious fish out of Florida’s waterways.

Although their reputed ability to reduce a human being to a skeleton in minutes is a myth, experts say the predatory fish could disrupt Florida’s freshwater ecosystems if they got loose, using their razor-sharp teeth to feed on the state’s native fish.

Kristina M. Dempsey, of Lake Worth, Fla., was charged with three misdemeanors, after the deal was carried out in the parking lot of a Wal-Mart in West Palm Beach, according to a report by the Florida Fish and Wildlife Conservation Commission. In an interview, she said she was simply trying to get rid of aquarium fish she no longer wanted in a more responsible manner than dumping them in a lake or canal.

The investigation began when an officer saw a notice to sell the piranhas on Craigslist. State wildlife investigator Jon Garzaniti sent Dempsey a text message, asking whether they could meet to make the deal for a total of $60.

“Sure. As long as you’re not a cop,” she responded, according to the report.

He replied that he was not and inquired why she had asked.

“Well, considering these fish are illegal and all, and you asked the same thing today that you had asked yesterday, given the same answer, it sounds like someone may be trying to build a report. Lol.”

She continued, “Or maybe I’m being overly paranoid. Either way, can’t be too sure now a days. It’s not like this is some kind of drug deal.”

They met Aug. 21 at the Wal-Mart parking lot, with Dempsey bringing the eight-inch fish in a bucket in her van. After briefly discussing their feeding requirements, the officer poured the fish into his own bucket, identified himself and called in two other officers as backup. He issued Dempsey citations for possession and sale of a prohibited non-native fish and sale of freshwater fish without a dealer’s license.

In an interview Wednesday, Dempsey expressed astonishment that her attempt to get rid of some aquarium fish she no longer wanted was the target of an undercover operation. She bought the fish from a man in Hollywood, Fla., concluded she no longer wanted them because their all-meat diet clouded her fish tank and decided to find another owner to care for them, selling them for much less than the $100 that she paid for the three of them.

“I’m not irresponsible enough to let them go in fresh water because I have respect for the environment and the ecosystem,” she said. “If you do have animals like this, instead of setting you up and treating you like a criminal, they should offer a way you could hand them over and surrender them if you don’t want them anymore.”

The state wildlife commission actually does hold exotic pet amnesty days throughout Florida, where reptiles, amphibians, birds, fish, mammals and invertebrates can be surrendered without penalty. They can also be surrendered outside of amnesty days.

Piranhas, native to the Amazon River and other South American waterways, have a sinister glamour rooted more in fiction than reality. In the 1967 James Bond film “You Only Live Twice,” the criminal mastermind Ernst Stavro Blofeld pushes a button that dumps an incompetent underling into a piranha tank, where the water churns around her for a minute or two until she’s gone.

Their reputation originated in part from Theodore Roosevelt’s account of a 1914 trip to the Amazon, where the former president saw the fish strip a cow carcass in a matter of minutes. Turns out the piranhas had been penned up and starved to put on a show for their illustrious visitor.

Evan D’Alessandro, visiting assistant professor of marine biology and fisheries at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, said the piranha’s reputation is more myth than reality.

Yes, piranhas have extremely sharp, interlocking teeth that can efficiently remove flesh. But they show little interest in attacking people, cows or other large animals. People routinely swim in water with piranhas, without being in the slightest danger, he said.