Jordi Chias / Pearlfish (Carapus acus) in anus of Sea cucumber (Stichopus regalis). These species have a commensal relationship, with the fish living in the gut of the sea cucumber. Catalonia, Spain. Mediterranean...

Franco Banfi / John Dory (Zeus Faber) in front of a wall covered on Yellow gorgonian (Eunicella cavolini) Stupiste Out dive site, Vis Island, Croatia, Adriatic Sea, Mediterranean

Franco Banfi / Forkbeard (Phycis phycis) on Teti wreck, Vis Island, Croatia, Adriatic Sea, Mediterranean

Franco Banfi / Scuba diver and Forkbeard (Phycis phycis) on Teti wreck, Vis Island, Croatia, Adriatic Sea, Mediterranean

Juergen Freund / Potato cods (Epinephelus tukula) Great Barrier Reef, Queensland, Australia