This sleek unicornfish, Naso hexacanthus, has turned a darker than normal color to help an endemic Hawaiian cleaner wrasse, Labroides phthirophagus, spot parasites, Hawaii. photo by David Fleetham Stock Photo - Afloimages
This sleek unicornfish, Naso hexacanthus, has turned a darker than normal color to help an endemic Hawaiian cleaner wrasse, Labroides phthirophagus, spot parasites, Hawaii. /photo by David Fleetham