Phylum Chordata
The Chordates have four common characteristics - a notochord, a dorsal nerve cord, pharyngeal slits and a post-anal tail. Chordates include lancets and tunicates, fish, birds, reptiles and amphibians and mammals.
Class Amphibia – Amphibians
Class Aves – Birds
Class Mammalia – mammals
Class Reptilia – Reptiles
Class Actinopterygii – ray-finned fishes
Class Sarcopterygii
Class Chondrichthyes – cartilaginous fishes
Class Cephalaspidomorphi – lampreys
Class Myxini – hagfishes
Class Pteraspidomorphi
Class Appendicularia – pelagic tunicates
Class Ascidiacea – sessile tunicates
Class Thaliacea – pelagic tunicates
Class Aves – Birds
Class Mammalia – mammals
Class Reptilia – Reptiles
Class Actinopterygii – ray-finned fishes
Class Sarcopterygii
Class Chondrichthyes – cartilaginous fishes
Class Cephalaspidomorphi – lampreys
Class Myxini – hagfishes
Class Pteraspidomorphi
Class Appendicularia – pelagic tunicates
Class Ascidiacea – sessile tunicates
Class Thaliacea – pelagic tunicates