Many species appear in cryptozoological literature, including mythical and folkloric animals, such as Bigfoot and the Loch Ness Monster, which have appeared commonly as cultural references, and within TV, movies, and other media.

A few species such as the okapi, discovered in 1901, and mountain gorilla, discovered in 1902, are also commonly used by cryptozoologists as examples of animals they say were previously thought to be cryptids, but are now known to exist.  These species are rarely anticipated by cryptozoologists before their discovery by science, but are nonetheless often depicted as hallmarks of cryptozoology.

Before 1912, the komodo dragon was thought to be a mythological creature and was called the giant monitor.