Rhinolophidae is a family of bats commonly known as horseshoe bats. There is also an extinct genus of bats, "Palaeonycteris." Horseshoe bats are closely related to the Hipposideridae. Horseshoe bats are divided into six subgenera and many species groups. The common ancestor of all horseshoe bats lived 34–40 million years ago. Horseshoe bats are found mostly in tropical or subtropical areas, including Africa, Asia, Europe, and Oceania.