Chordates are animals possessing a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail for at least some period in their life cycles. Taxonomically, the phylum includes the subphyla Vertebrata, which includes mammals, fish, amphibians, reptiles, and birds; Tunicata, which includes salps and sea squirts; and Cephalochordata, comprising the lancelets. Members of the phylum Chordata are bilaterally symmetric, deuterostome coelomates, and the vertebrate chordates display segmentation.


  1. Acanthodii
  2. Actinopterygii
  3. Amphibia
  4. Anaspida
  5. Appendicularia
  6. Ascidiacea
  7. Aves
  8. Cephalaspidomorphi
  9. Chondrichthyes
  10. Conodonta
  11. Leptocardii
  12. Mammalia
  13. Myxini
  14. Petromyzontida
  15. Placodermi
  16. Pteraspidomorphi
  17. Reptilia
  18. Sarcopterygii
  19. Sorberacea
  20. Thaliacea
  21. Thelodonti