Spiny Devilfish, Demon Stinger

"I. didactylus is a piscivorous ambush predator. It is nocturnal and typically lies partially buried on the sea floor or on a coral head during the day, covering itself with sand and other debris to further camouflage itself. It has no known natural predators. When disturbed by a scuba diver or a potential predator, it fans out its brilliantly colored pectoral and caudal fins as a warning. Once dug in, it is very reluctant to leave its hiding place. When it does move, it displays an unusual mechanism of subcarangiform locomotion - it crawls slowly along the seabed, employing the four lower rays (two on each side) of its pectoral fins as legs." (see pics 3 & 4)
Source : - http://en.wikipedia.org/wiki/Inimicus_didactylus