Elasmobranchii (pronounced /ɛˌlæzmɵˈbræŋki.aɪ/) is the subclass of cartilaginous fish that includes skates, rays (batoidea), and sharks (selachii).
Fossilised shark teeth are known from the early Devonian, around 400 million years ago. During the following Carboniferous period, the sharks underwent a period of diversification, with many new forms evolving. Many of these became extinct during the Permian, but the remaining sharks underwent a secon...
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Elasmobranchii (pronounced /ɛˌlæzmɵˈbræŋki.aɪ/) is the subclass of cartilaginous fish that includes skates, rays (batoidea), and sharks (selachii).
Fossilised shark teeth are known from the early Devonian, around 400 million years ago. During the following Carboniferous period, the sharks underwent a period of diversification, with many new forms evolving. Many of these became extinct during the Permian, but the remaining sharks underwent a second burst of adaptive radiation during the Jurassic, around which time the skates and rays first appeared. Many surviving orders of elasmobranch date back to the Cretaceous, or earlier.
Elasmobranchii is one of the two subclasses of cartilaginous fish in the class Chondrichthyes, the other being Holocephali (chimaeras). For features that distinguish Elasmobranchii from Holocephali, see those articles. This classification includes great white sharks and the extinct megalodon.
Members of the elasmobranchii subclass have no swim bladders, five to...
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