Rays, skates and sawfish make up the Rajiformes, an order of cartilaginous fish containing 12 families. Fish in this group generally have flat bodies and a large pectoral fin that forms a disc. The undulation of this fin propels the fish through the water. Though most are found in marine waters, there are some freshwater species - notably the river rays. Some species of stingray have a toxin which can be harmful, and even fatal, to humans.

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