Bilateria

Bilateria Fossil range: Ediacaran - Recent
Scientific classification
Kingdom: Animalia Subkingdom: Eumetazoa (unranked) Bilateria Hatschek, 1888

Bilateria are all animals having a bilaterally symmetrical animals, they have front and a back end, as well as an upside and downside.

Subgroups

• Deuterostomia
  • Echinodermata (20,000 species)
  • Hemichordata (71 species)
  • Chordata (63,000 species)
• Protostomia
  • Ecdysozoa (6,201,600-10,213,600 species)
  • Lophotrochozoa
  • Platyzoa
• Chaetognatha (affiliation uncertain)
• Cycliophora
• Mesozoa

Other referneces

• Helfenbein, Kevin G., H. Matthew Fourcade, Rohit G. Vanjani, and Jeffrey L. Boore (2004). The mitochondrial genome of Paraspadella gotoi is highly reduced and reveals that chaetognaths are a sister group to protostomes. Proceedings of the National Academy of Sciences of the United States of America 101(29), July 20 2004: 10639-10643.
• Papillon, Daniel, Yvan Perez, Xavier Caubit, and Yannick Le Parco (2004). Identification of chaetognaths as protostomes is supported by the analysis of their mitochondrial genome. Molecular Biology and Evolution 21(11), November 2004: 2122-2129.