The paraxial mesoderm is the mesoderm located bilaterally adjacent to the notochord and neural tube[GO].

http://upload.wikimedia.org/wikipedia/commons/6/64/Gray19_with_color.png

Mesoderm lateral to the neural tube and notochord that is divided into cranial and post-cranial portions. The trunk portions further segment into somites.[AAO]

note that all AOs differ in the relationship between this structure and the mesoderm; in ZFA it is a subclass (and this is implied by the GO definition and GO relationships), in AAO it is part of, and in EHDAA2 it develops from the mesoderm (but in EHDAA2 the naming convention is to use 'paraxial mesenchyme', rather than 'paraxial mesoderm'). Also in ZFA it is part of the trunk whereas this conflicts with the division into head and trunk in ehdaa2 (which we follow here)

paraxial mesenchyme, somitic mesoderm

uberon

mesoderma paraxiale

Presently, Cephalochordata, Urochordata, and Vertebrata are placed as subphyla of the phylum Chordata, in which the overall organization of embryonic tissues (dorsal hollow nerve cord, ventral digestive tract, axial notochord, and bilateral paraxial mesoderm) is largely conserved. In contrast, the echinoderms and hemichordates are sister groups of the chordates and they lack the notochord and paraxial mesoderm. Thus, the basic mesodermal organization of vertebrates must have appeared first in the common ancestor of the chordates.[well established][VHOG]

UBERON:0003077

http://purl.obolibrary.org/obo/uberon.owl, http://purl.obolibrary.org/obo/cl.owl

• presumptive paraxial mesoderm

• intermediate mesoderm

• presomitic mesoderm
• trunk paraxial mesoderm