A woman has died after being hit by a stingray which jumped onto her boat off the Florida Keys in America.

Judy Kay Zagorski, 57, of Pigeon, Michigan, was in the front of a boat going 25 miles per hour (40kph) off Marathon, about 50 miles (80km) northeast of Key West.

A 75 pound (34kg) spotted eagle ray leapt from the water and hit her in a freak collision.

A medical examiner said Mrs Zagorski was struck in the face and died of skull fractures and brain injuries, not from the animal's poisonous barb.

Jorge Pino, spokesman for the Florida Fish and Wildlife Conservation Commission, said the collision knocked Mrs Zagorski backward, onto the floor of the boat.

"It happened within a fraction of a second, there's nothing that anybody could have done any differently. There's not a thing that the father, who was operating the vessel, could have done differently, there's nothing that the victim could have done differently," he said.

Spotted eagle rays can grow to about 17 feet (5m) long, including the tail, and weigh up to 500 pounds (227kg). Some have wingspans as wide as 10 feet (3m).

They are not aggressive and use the venomous barb at the end of their tail for defence.

In 2006, a South Florida man was critically injured when a stingray flopped into his boat and stung him. James Bertakis, 82, underwent surgery after the stingray left a foot-long barb in his heart, and has since recovered.

Crocodile Hunter, Steve Irwin, was killed in 2006 when a stingray's barb pierced his heart off Australia's Great Barrier Reef.

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