Cladogram for KINDOM ANIMALIA (=Metazoa)
Modified from Tree of Life for Kingdom Animalia (after Ruppert & Barnes 1994 p. 1052).
========================================== Porifera (sponges) | | =================================== Cnidaria (jellyfish, anemones, corals, etc.) | | | | ================================ Ctenophora (comb-jellies) | | | | | | ======================== Platyhelminthes (flatworms, tapeworms,etc.) | | | | | | | | =(branch uncertain)== Aschelminthes (pseudocoelomates: nematodes,rotifers,etc.) | | | | | <<=M=| | | =P==| | ================= Nemertea (ribbon worms) | | | | | | | | | | | | | | ======== Sipuncula (peanut worms) | =E==| | | ===| | ======| | | | | | | | | ======== 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
Traits supporting each clade (** plesiomorphic- a primitive state, not unique to clade):
M= METAZOA: a) true multicellularity (coordinated & differentiated cell types, no real symmetry, lack endoderm, no true gut), b) monociliated cells**, c) radial, indeterminate cleavage, d) blastula stage larva**, e) diplosome**
E= EUMETAZOA: a) diploblastic organization, b) true tissues, c) gastrula stage, d) blind gut (no anus)
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, e) trochophore-like larva
C= COELOMATE PROTOSTOMES: a) coelom via schizocoely, b) flow-through gut (anus present)
D= DEUTEROSTOMIA: a) radial, indeterminate cleavage**, b) mesoderm from epithelial cells, c) coelom via enterocoely, d) blastopore yields anus, e) tripartite coelom & body plan, f) monociliated cells**
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Copyright © 1998 by A. Richard Palmer. All rights reserved. (revised Apr. 4, 1998)