Pascal Kobeh / Ocan Pacifique - Nouvelle caldonie - Gros plan de la tte d'un nason licorne (Naso brevirostris) de nuit Pacific Ocean - New Caledonia - A close-up of the head of a spotted or longnose unicornfish (Na...

Magnus Lundgren / Wild Wonders of China / Spotted unicornfish (Naso brevirostris) Green Island, a small volcanic island in the Pacific Ocean , Taiwan

Georgette Douwma / Brown tang (Zebrasoma scopas). North Sulawesi, Indonesia.

David Fleetham / Green sea turtle (Chelonia mydas) followed closely by Spotted unicorn fish (Naso brevirostris) which feeds on turtle feces, Hawaii.

Pascal Kobeh / Bluestreak cleaner wrasse (Labroides dimidiatus) cleaning Spotted unicornfish (Naso brevirostris) Palau. Philippine Sea.

Pascal Kobeh / Diagonal-banded / Yellowbanded sweetlips (Plectorhinchus lineatus) cleaning Spotted unicornfish (Naso brevirostris) Palau. Philippine Sea.

Fred Bavendam / Spotted Unicornfish (Naso brevirostris), Great Barrier Reef, Australia

Joel Sartore / Photo Ark / Bignose unicornfish (Naso vlamingii) portrait, Aquarium of Boise. Captive, occurs in Indo-Pacific.

Joel Sartore / Photo Ark / Bignose unicornfish (Naso vlamingii) head portrait, Aquarium of Boise. Captive, occurs in Indo-Pacific.

Joel Sartore / Photo Ark / Whitecheek surgeonfish (Acanthurus nigricans) portrait, The National Aquarium, Abu Dhabi. Captive, occurs in Pacific Ocean.

David Hall / Yellow tangs (Zebrasoma flavescens) and Brown surgeonfish (Acanthurus nigrofuscus) cleaning a Green sea turtle (Chelonia mydas) at "cleaning station", feeding on alage on turtle's skin and shell,...

David Hall / Three Green sea turtles (Chelonia mydas) at a cleaning station with Brown Surgeonfish (Acanthurus nigrofuscus) waiting nearby, Big Island, Hawaii, Pacific Ocean. Endangered.