Batoidea

Scientific name : Batoidea

The superorder Batoidea contains more than 500 species; they are usually known as "rays," but the superorder includes stingrays, sawfishes and guitafishes.
Their bodies are flat, and their gills slits can be found on their underside, while in sharks (which are related to Batoids) are on the sides of the head. Guitarfishes and sawfishes are an exception, since their bodies are more streamlined and similar to those of a shark.
Batoids are viviparous, though rays are not. They usually feed on mollusks and crustaceans, and sometimes fish, though manta rays feed on plankton.