Concept
Automatic taxobox | name = Eumetazoans | fossil_range = Ediacaran - Present, | image = File:Animalia diversity.jpg|300px rect 0 0 400 290 [[Mollusca]] rect 400 0 800 275 [[Scyphozoa]] rect 0 300 400 775 [[Chordata]] rect 400 280 800 775 [[Arthropod]] rect 0 800 800 1100 [[Annelida]] | image_caption = Diversity of eumetazoans | display_parents = 7 | taxon = Eumetazoa | authority = Buetschli, 1910 | subdivision_ranks = Phyla | subdivision = * Ctenophora † Trilobozoa Chancelloriida †Proarticulata †Petalonamae ParaHoxozoa (unranked) Placozoa Cnidaria Bilateria (unranked) Xenacoelomorpha? Nephrozoa (unranked) Superphylum Deuterostomia Chordata "Ambulacraria" Hemichordata Echinodermata Xenacoelomorpha? Protostomia (unranked) Superphylum Ecdysozoa Kinorhyncha Loricifera Priapulida Nematoda Nematomorpha Onychophora Tardigrada Arthropoda Spiralia (unranked) Orthonectida Rhombozoa Chaetognatha Superphylum Platyzoa Platyhelminthes Gastrotricha Rotifera Acanthocephala Gnathostomulida Micrognathozoa Cycliophora Superphylum Lophotrochozoa Hyolitha† Nemertea Phoronida Bryozoa Entoprocta Brachiopoda Mollusca Annelida | synonyms = *Enterozoa Lankester, 1877, em. Beklemishev Epitheliozoa Ax, 1996 Diploblast Lankester, 1873 Histozoa Ulrich, 1950 Eumetazoa (), also known as diploblasts, Epitheliozoa, or Histozoa', are a proposed basal animal clade as a sister group of the Porifera (sponges). The basal eumetazoan clades are the Ctenophora and the ParaHoxozoa. Placozoa is now also seen as a eumetazoan in the ParaHoxozoa. The competing hypothesis is the Myriazoa clade. Several other extinct or obscure life forms, such as Iotuba and Thectardis, appear to have emerged in the group. Characteristics of eumetazoans include true tissues organized into germ layers, the presence of neurons and muscles, and an embryo that goes through a gastrula stage. Some phylogenists once speculated the sponges and eumetazoans evolved separately from different single-celled organisms, which would have meant that the animal kingdom does not form a clade (a complete grouping of all organisms descended from a common ancestor).
