Moray eels live in shallow water among reefs and rocks and hide in crevices. They differ from other eels in having small rounded gill openings and in generally lacking pectoral fins. Their skin is thick, smooth, and scaleless, while the mouth is wide and the jaws are equipped with strong, sharp teeth, which enable them to seize and hold their prey, mostly other fishes, but also to inflict serious wounds on their enemies, including humans.