Bilateria

Bilateria Fossil range: Ediacaran–Recent
Scientific classification
Domain:	Eukaryota
(Unranked) :	Opisthokonta
Kingdom:	Animalia
Subkingdom:	Eumetazoa
(Unranked) :	Bilateria Hatschek, 1888
Phyla:	Orthonectida Rhombozoa Acoelomorpha (disputed) Chaetognatha Superphylum Deuterostomia Chordata Hemichordata Echinodermata Xenoturbellida Vetulicolia † Protostomia (unranked) Superphylum Ecdysozoa Scalidophora (unranked) Kinorhyncha Loricifera Priapulida Nematoda Nematomorpha Panarthropoda (unranked) Lobopodia † Onychophora Tardigrada Arthropoda Superphylum Platyzoa Platyhelminthes Gastrotricha Rotifera Acanthocephala Gnathostomulida Micrognathozoa Cycliophora Superphylum Lophotrochozoa Sipuncula Hyolitha † Nemertea Phoronida Bryozoa Entoprocta Brachiopoda Mollusca Annelida Echiura

The Bilateria are all animals having a bilateral symmetry, i.e. they have a front and a back end, as well as an upside and downside. Radially symmetrical animals like jellyfish have a topside and downside, but no front and back. The bilateralians are a subregnum (a major group) of animals, including the majority of phyla; the most notable exceptions are the sponges and cnidarians.