Class Chondrichthyes (Phylum Chordata)
Examples and Traits
Sharks, Rays and Chimera belong to Class Chondrichthyes. There is about 750 species in Class Chondrichthyes. They have Jaws and a cartilage skeleton, which evolved from a bony skeleton. They acute chemoreception. They also have a very sharp lateral line system, which is used to detect vibrations and movement in the water around them. They can also detect electric fields. they have rows of teeth, and tooth-like scales on their bodies. Their fins are paired. If they stop swimming, they will actually sink. They perform internal fertilization, and some are viviparous. They have kidneys, a two chambered heart, and a closed circulatory system.