Stingrays are a group of rays, which are cartilaginous fishes related to sharks.
Most stingrays have one or more barbed stings (modified from dermal denticles) on the tail, which are used exclusively in self-defense.
The stinger is covered with a thin layer of skin, the integumentary sheath, in which the venom is concentrated.
A few members of the suborder, such as the manta rays and the porcupine ray, do not have stingers.
Stingrays are often confused for skates, who have more triangular wings and scoot with their pectoral fins to move.