Aural flap

An aural flap was a part of an Ithorian's anatomy. After the metamorphosis, Ithorians lost an aural flap.

Behind the scenes
Aural flaps were first mentioned in Monsters and Aliens from George Lucas, a book published in 1993. Lucasfilm employee Leland Chee, who maintains the Holocron continuity database, has indicated that information contained in the book is non-canonical. It was later made canonical with the publishing of Musings of an Ithorian on Star Wars Hyperspace.