A bluestreak cleaner wrasse searching the mouth of a clown sweetlips for parasites, Yap, Micronesia, Pacific

This fish is having its gills cleaned by a cleaner wrasse so it opens wide allowing the fish to come in and feed on parasites, Raja Ampat, Indonesia.

Masai giraffe (Giraffa camelopardalis tippelskirchi) cleaning its nose, Masai Mara National Reserve, Kenya, East Africa, Africa

Inspecting horse's teeth, England, United Kingdom, Europe

Major Mitchell Cockatoo perched on branch, Queensland, Australia

Moray eel with cleaner shrimp (Gymnothorax sp).

Eider duck (Somateria mollissima), male. Male appearing to call someone. Actual behaviour is scratching and cleaning mouth with claw on webbed foot, while drifting with winter raft , Scotland, United Kingdom

Coral Grouper (Cephalopholis miniata) being cleaned by a BruunÃs Cleaning Partner Shrimp (Urocaridella aontonbruunii) this incredible gaping action allows the shrimp uninhibited access to the mouth and gills.Red Sea.

Coral Hind/Trout (Cephalopholi miniata). Mouth open. Nuweiba, South Sinai, Egypt, Red Sea.

Coral Grouper (Cephalopholis miniata) being cleaned by a BruunÌs Cleaning Partner Shrimp (Urocaridella aontonbruunii) this incredible gaping action allows the shrimp uninhibited access to the mouth and gills. Red Sea.

A man brushing his teeth

Cleaner shrimp works on moray eel.

Coral Grouper (Cephalopholis miniata) being cleaned by a BruunÌs Cleaning Partner Shrimp (Urocaridella aontonbruunii) this incredible gaping action allows the shrimp uninhibited access to the mouth and gills. Red Sea.

Starry Toadfish; cleaner shrimp on mouth (Arothon stellatus). Indo Pacific

Green sea turtle (Chelonia mydas) at cleaning station (note fishing hook embedded in mouth) at Olowalu Reef on the west side of the island of Maui, Hawaii, USA

Atlantic goliath grouper (Epinephelus itajara) with open mouth at cleaning station. Dive site John Pennekamp Coral Reef State Park, Key Largo, Florida Keys, Florida, USA, North America

Symbiotic behaviour Symbiosis of jewel perch vermillion seabass (Cephalopholis miniata) lies at cleaning stationwith mouth wide open showing teeth rows of teeth motionless in coral reef lets cleaner wrasse bluestreak cleaner wrasse (Labroides dimidiatus) rid itself of parasites, Indian Ocean, Mascarene Islands, Mauritius, Africa

African bush elephant (Loxodonta africana) in the water washing and lifting river grass with its trunk and tusks in Chobe National Park, Chobe, North-West, Botswana

While a Hawaii Cleaner Wrasse (Labroides phthirophagus) searches for parasites in its mouth, a Reef Manta Ray (Mobula (formerly Manta) alfredi) hovers over a reef cleaning station off the Kona Coast, the Big Island, Hawaii, USA during the summer. This par

Hawaii, Yellowfin goatfish (Mulloidichthys vanicolensis) and an endemic Hawaiian cleaner wrasse (Labroides phthirophagus) taking a close look in it's mouth.

striped remora or live sharksucker remora cleaning scraps from inside the mouth of a lemon shark Negaprion brevirostris resting on the bottom is a strong current Thought to be a parasite this is one of the first images showing a benefit for the shark in this relationship West End Grand Bahamas Atlantic Ocean