Chordata
Nota de aplicación
Phylum that includes common vertebrates such as fishes, amphibians, reptiles, birds, mammals, as well as the tunicates and lancelets. With few exceptions, chordates are active animals with bilaterally symmetric bodies that are longitudinally differentiated into head, trunk, and tail. The most distinctive morphological features of chordates are the notochord, nerve cord, and visceral clefts and arches.