Juergen Freund / Coleman shrimp (Periclimenes colemani) on a Fire urchin (Asthenosoma varium) Moluccas Islands, Indonesia.

Doug Perrine / Yellow edged moray eel {Gymnothorax flavimarginatus} having mouth cleaned by Humpback cleaner shrimp {Lysmata amboinensis} Sabah Borneo (Non-ex).

Doug Perrine / Nassau grouper {Epinephelus striatus} mouth being cleaned of parasites by clearner shrimp, Turks & Caicos, Caribbean Sea (Non-ex).

David Hall / Sea urchin shrimp on venemous urchin {Periclimenes colemani & Asthenosoma} Papua New Guinea

Juergen Freund / Banded coral (Cleaning) shrimp on coral, Caribbean Sea off Cuba.

Magnus Lundgren / Wild Wonders of China / Larval banded coral shrimp (Stenopus hispidus) at night, Kenting National Park, Hengchun Peninsula, Taiwan

David Fleetham / Yellowmargin moray eel (Gymnothorax flavimarginatus) with a Banded coral shrimp (Stenopus hispidus) inspecting it for parasites, Hawaii.

David Fleetham / Banded boxer / coral shrimp (Stenopus hispidus) on the nose of a giant moray eel (Gymnothorax javanicus), checking for parasites. Yap, Micronesia.

Alex Mustard / Pair of Coleman shrimps (Periclimenes colemani) make their home in a fire urchin (Asthenosoma varium). The female is larger. Fire urchins are one of the largest and most venomous urchins, their bright...

Alex Mustard / Pair of Coleman shrimps (Periclimenes colemani) living in a fire urchin (Asthenosoma varium). The female is the larger shrimp. Fire urchins are one of the largest and most venomous urchins, their brig...

Alex Mustard / Coleman shrimp (Periclimenes colemani) close up, on a fire urchin (Asthenosoma varium). Anilao, Batangas, Luzon, Philippines. Verde Island Passages, Tropical West Pacific Ocean.

Franco Banfi / Couple of banded boxer shrimp (Stenopus hispidus) Tubbataha Reef Natural Park, UNESCO World Heritage Site, Sulu Sea, Cagayancillo, Palawan, Philippines