Revised clade from Tree of Life for Kingdom Animalia (after Ruppert & Barnes 1994 p. 1052).

     ========================================== Porifera (sponges)
     |
     |      =================================== Cnidaria (jellyfish, anemones, corals, etc.)
     |      |
     |      |  ================================ Ctenophora (comb-jellies)
     |      |  |
     |      |  |       =(placement uncertain)== pseudocoelomates(nematodes,rotifers,etc.)
     |      |  |       |
     |      |  |       |  +==================== Platyhelminthes(flatworms,tapeworms,etc.)
     |      |  |       |  |
<<===|      |  |   =P*=|  |   ================= Nemertea (ribbon worms) 
     |      |  |   |   |  |   |
     |      |  |   |   |  |   |        ======== Sipuncula (peanut worms)
     |  ====|  |   |   ===|   |  ======|
     |  |   |  |   |      |   |  |     ======== Mollusca(snails, clams, squids, etc.)
     |  |   |  |   |      =C*=|  |
     |  |   |  |   |          |  |     ======== Echiura (proboscis worms)
     |  |   |  |   |          ===|     |
     |  |   |  |   |             |  ===|  ===== Pogonophora (beard worms, vent worms)
     |  |   ===|   |             |  |  ===|
     |  |      |   |             ===|     ===== Annelida(segmented worms)
     |  |      |   |                |
     ===|      |   |                |  ======== Onychophora (velvet worms)
        |      |   |                ===|
        |      |   |                   ======== Arthropoda(insects, spiders, crabs, etc.)
        |      =B*=|
        |          |   ======================== Chaetognatha (arrow worms)
        |          |   |
        |          =D*=|  ===================== lophophorates (bryozoans, brachiopods, etc.)
        |              |  |
        |              ===|  ================== Echinodermata(starfish, urchins, etc.)
        |                 |  |
        |                 ===|  =============== Hemichordata (acorn worms, pterobranchs)
        |                    ===|
        |                       =============== Chordata (sea squirts, vertebrates, etc.)
        |
        =====(phyla of uncertain affinity)===== Placozoa, Monoblastozoa, Rhomobozoa, Orthonectida

B= BILATERIA: a) bilateral symmetry,b) cephalization, c) triploblastic organization (extensive mesoderm), d) organ-system level of organization, e) protonephridia

P= PROTOSTOMIA: a) spiral, determinate cleavage, b) mesoderm from mesenchyme cells, c) mouth (and sometimes anus) from blastopore, d) multiciliated cells

C= COELOMATE PROTOSTOMES: a) coelom via schizocoely

D= DEUTEROSTOMIA: a) radial, indeterminate cleavage**, b) coelom via enterocoely, c) blastopore yields anus, d) tripartite coelom & body plan, e) monociliated cells (primitively)

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