The Orange-lined Triggerfish, Orange-striped Triggerfish or Undulated Triggerfish (Balistapus undulatus) is a triggerfish of the tropical Indo-Pacific area. It is the only member of the genus Balistapus. They reach a maximum size of about 30 cm. They feed on coral, crabs and invertebrates. They are found up to around 50 m deep in tropical waters.