Pascal Kobeh / Bruun's cleaner shrimp (Urocaridella antonbrunii) cleaning mouth of Coral hind (Cephalopholis miniata), in coral reef. Moheli, Comoros.

Georgette Douwma / White-margined Moray Eel (Enchelycore schismatorhynchus) being cleaned by a Rock Shrimp (Urocaridella sp). Lenmbeh Strait, North Sulawesi, Indonesia.

David Fleetham / Rock Shrimp (Urocaridella antonbrunii) on a Common Octopus (Octopus cyanea). Tulamben, Bali, Indonesia.

David Fleetham / Honeycomb moray eel (Gymnothorax favagineus) surrounded by hinge-beak shrimp, (Rhynchocinetes sp) with cleaner shrimp, (Urocaridella sp) inspecting its chin, Indonesia.

Alex Mustard / Emperor angelfish (Pomacanthus imperator) with Cleaner shrimp (Urocaridella sp.) grooming it. South Ari Atoll, Maldives. Indian Ocean.

Pascal Kobeh / Bruun's cleaner shrimps (Urocaridella antonbrunii) cleaning Emperor angelfish (Pomacanthus imperator) Maldives. Indian Ocean.

Pascal Kobeh / Bruun's cleaner shrimps (Urocaridella antonbrunii) cleaning a giant moray (Gymnothorax javanicus) Maldives. Indian Ocean.

Franco Banfi / Giant moray (Gymnothorax javanicus) with Rock shrimp, Urocaridella sp. , Maldives, Indian Ocean

Franco Banfi / Rock shrimp (Urocaridella sp.) Maldives, Indian Ocean

Juergen Freund / Cleaner shrimps (Urocaridella sp) Bali, Indonesia.

Fred Bavendam / Redlip Parrotfish (Scarus rubroviolaceus) cleaned by Clear Cleaner Shrimp (Urocaridella antonbruunii), Bali, Indonesia

Chris Newbert / Giant Moray Eel (Gymnothorax javanicus) being cleaned by a Cleaner Shrimp (Urocaridella sp), Red Sea, Egypt