Wikipedia
Cryptofiction
Cryptofiction is fiction based on cryptozoology. Cryptofiction combines elements of native legend, historical records and eyewitness accounts concerning a mythical or legendary creature such as Bigfoot and the Loch Ness Monster or any creature studied by cryptozoologists.
Examples include works by Jules Verne ( The Mysterious Island), Arthur Conan Doyle ( The Lost World), and Edgar Rice Burroughs ( The Land That Time Forgot), and recent fiction such as Michael Crichton ( Jurassic Park) and Steve Alten (the Meg series and The Loch).