Sharks and Rays

Elasmobranchii (/ɪˌlæzməˈbræŋkiaɪ/) is a subclass of Chondrichthyes or cartilaginous fish, including the sharks (superorder Selachii) and the rays, skates, and sawfish (superorder Batoidea). Members of this subclass are characterised by having five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins and small placoid scales on the skin. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the...