Elasmobranchii is the subclass of cartilaginous fish that includes skates, rays (batoidea), and sharks (selachii).
Summary
Elasmobranchii is one of the two subclasses of cartilaginous fishes 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 seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins, and small placid scales. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper. The eyes have a tapetum lucidum. The inner margin of each pelvic fin in the male fish is grooved to constitute a clasper for the transmission of sperm. These fishes are widely distributed in tropical and temperate waters.
References
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Last updated on Saturday September 06, 2008 at 16:21:34 PDT (GMT -0700)
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