Chaetodon oxycephalus also commonly referred as the Lined Butterflyfish, Pig-face butterflyfish or Spot-nape butterflyfish is often confuses with Chaetodon lineolatus, the main difference being the eye band shape: in Chaetodon lineolatus the band is expanded on nape, with a white spot in the middle. In Chaetodon oxycephalus the band is interrupted, and leaves a black spot on nape.
The Spot-nape butterflyfish is distributed in the Indo-Pacific region from Sri Lanka to Queensland, north to Indonesia and the Philippines. Found in coral-rich areas of coastal reefs as well as clear waters of seaward reefs at 10-40 m depth and is known to feed mainly on coral polyps and anemones.
Chaetodon oxycephalus is the largest butterflyfish and a poor-surviving species in captivity.
Butterflyfish are not recommended for reefs as they will pick at or eat a wide variety of corals, fan worms, and other invertebrates. Most Butterflyfish are known to pick at Aiptaisia, a parasitic anemone.