They are two species of Long-nose Butterfly fish, "Long" Long Nose Butterflyfish, "Forcipiger longirostris" and the "Yellow" Long Nose Butterflyfish or Forcepsfish, " Forcipiger flavissimus"
These are easily distinguished on the basis of relative snout length. "Forcipiger longirostrisand" is the "winner by a nose" as it's scientific name implies.