The identity of the victim was not reported but Jodie Soule told the South Florida Sun Sentinel the plane belonged to her husband, Paul Soule, and he was the only person on board. She said she believes her husband was killed in the accident Saturday.
The plane took off from Fort Lauderdale Executive Airport and was headed to Leesburg International Airport in Central Florida, said Arlene Salac, a spokeswoman for the Federal Aviation Administration.
Palm Beach County Fire Rescue said the aircraft crashed at about 1:25 p.m. in a remote section of the Loxahatchee Wildlife Refuge in the north part of the Everglades.
Rescuers were initially unable to reach the crash site using air boats, said Fire Rescue Capt. Albert Borroto. Authorities finally reached the site by Saturday evening.
The FAA and National Transportation Safety Board launched an investigation into the cause of the crash.
Paul Soule had U.S. Air Force pilot training and FAA flight instructor ratings, his company's website said. He had "18,000 hours of accident- and incident-free flying" over the course of 57 years, it said.