Protostomia Fossil range: Ediacaran - Recent | |
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Scientific classification
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Eukaryota | |
Opisthokonta | |
Eumetazoa | |
Protostomia | |
Subdivisions: |
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Protostomia (from the Greek: mouth first) are a clade of animals. Together with the deuterostomes and a few smaller phyla, they make up the Bilateria, mostly comprising animals with bilateral symmetry and three germ layers. The major distinctions between deuterostomes and protostomes are found in embryonic development.