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Animals

Metazoa 


     =========================================== Porifera  (sponges) 
     |
     |        ================================== Cnidaria  (jellyfish, anemones, corals, etc.) 
     |        |
     |        |  =============================== Ctenophora  (comb-jellies) 
     |        |  |
     |        |  |                        ====== Arthropoda  (insects, spiders, crabs, etc.) 
     |        |  |                        |
     |        |  |                     ===|===== Onychophora  (velvet worms) 
     |        |  |                     |  |
     |  ======|  |               ======|  ====== Tardigrada  (water bears) 
     |  |     |  |               |     |
     |  |     |  |               |     |  ====== Annelida  (segmented worms) 
     |  |     |  |               |     ===|
<<===|  |     |  |               |        |  === Pogonophora 
     |  |     |  |               |        ===|
     |  |     |  |            ===|           === Vestimentifera 
     |  |     |  |            |  |
     |  |     ===|            |  |============== Echiura 
     |  |        |            |  |
     |  |        |         ===|  |============== Mollusca  (snails, clams, squids, etc.) 
     |  |        |         |  |  |
     |  |        |         |  |  =============== Sipuncula 
     |  |        |     ==P=|  |
     |  |        |     |   |  ================== Nemertea  (ribbon worms) 
     |  |        |     |   |
     |  |        |     |   ===================== Platyhelminthes  (flatworms) 
     |  |        |     |
     ===|        |  ===|            ============ Chordata  (vertebrates and relatives) 
        |        |  |  |         ===|
        |        |  |  |      ===|  ============ Hemichordata 
        |        |  |  |      |  |
        |        |  |  |   ===|  =============== lophophorates 
        |        ===|  |   |  |
        |           |  ==D=|  ================== Chaetognatha 
        |           |      |
        |           |      ===================== Echinodermata  (starfish, urchins, sea cucumbers, etc.) 
        |           |
        |           ============================ pseudocoelomates 
        |
        |======================================= Placozoa 
        |
        |======================================= Monoblastozoa 
        |
        |======================================= Rhomobozoa 
        |
        ======================================== Orthonectida
Tree modified from Brusca and Brusca (1990).
Note that this is a fairly traditional view of animal phylogeny, and other recent papers have substantially different arrangements. We will soon present an up to date discussion of metazoan relationships on this page. For the time being, please refer to the papers listed in the References section

In the tree, the descendents of the branch labelled "P" are the protostomes, of that labelled "D" are the deuterostomes.

Containing clade(s): Eukaryotes

Table of Contents

References

References

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Adoutte, A., G. Balavoine, N. Lartillot, and R. de Rosa.  1999. 
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Balavoine, G.  1998.  Are Platyhelminthes coelomates without 
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