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

Hiroya Minakuchi / Coleman's Shrimp (Periclimenes colemani) living among the venomous spines of a sea urchin, Sulu Sea, Borneo, Malaysia

Birgitte Wilms / Coleman's Shrimp (Periclimenes colemani) pair with shed carapace, Papua New Guinea

Fred Bavendam / Fire Urchin (Asthenosoma varium) that is host to a pair of Coleman's Shrimp (Periclimenes colemani) and parasitic Snails (Leutzenia asthenosomae), Bali, Indonesia

Fred Bavendam / Coleman's Shrimp (Periclimenes colemani) pair living among the spines of a Fire Urchin (Asthenosoma varium), Milne Bay, Papua New Guinea

Fred Bavendam / Coleman's Shrimp (Periclimenes colemani) pair living among the spines of a Fire Urchin (Asthenosoma varium), Milne Bay, Papua New Guinea

Fred Bavendam / Coleman's Shrimp (Periclimenes colemani) pair living in venomous spines of a Fire Urchin (Asthenosoma varium), Bali, Indonesia

Constantinos Petrinos / Sea urchin shrimp {Periclimenes colemani} on Sea urchin {Asthenosoma varium} Indonesia Sulawesi

Juergen Freund / Commensal Sea urchin shrimp {Periclimes colmani} amongst spines of poisonous sea urchin. Indo-Pacific

Ian Coleman / Illustration of human diver silhouette, for scale purposes.

Ian Coleman / Illustration of fins of Sand tiger shark (Carcharias taurus). Endangered/threatened species.

Ian Coleman / Illustration of Blue shark (Prionace glauca), Carcharhinidae. Endangered / threatened species.).