Southern Blue Devil

Found singly, pairs or in small schools, during the day sheltering in caves, crevices, and under ledges of inner and outer rocky reefs, dispersing at night to feed over the reef.
They feed nocturnally on crustaceans, small fish and molluscs.
Eastern Indian Ocean - Australia

Devilfish are recognised by their long fins, are very secretive and usually found in caves under ledges or crevices of reefs.