DEVIL STINGER or DEMON STINGER Inimicus didactylus ©reefwondersdotnet
You can see from in wonderful photo by Andrea & Antonella Ferrari where they got their name...
Inimicus didactylus, also known as Demon Stinger or Devil Stinger, is a member of the Inimicus genus of venomous fishes, closely related to the true stonefishes. It can reach a body length of 25 cm (10 in) and is irregularly surfaced with spines and a knobby appearance. The fish has venomous spines to ward off enemies. The fish are nocturnal, and often dig themselves partially into the sandy seabed during the day. The body is red or sandy yellow and well camouflaged on sandy and coral seabeds.
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.
Source: http://en.wikipedia.org/wiki/Inimicus_didactylus
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