Manta rays belong to the family Mobulidae, which contains one genus with two species of manta (potentially three) and nine different mobula rays, also known as "devil rays" for the horn-like appendages they use in foraging on small zooplankton and for sensory perception. The oceanic manta ray, Mobula birostris, (formerly known as Manta birostris) is considered to be among the most recently appearing cartilaginous fish (five million years) in the world's oceans and the most highly advanced members of the approximately 1100 species of elasmobranch fish, including the sharks, skates, rays, and little-known chimaeras.