bilaterian protostome http://purl.obolibrary.org/obo/NCBITaxon_33317 https://en.wikipedia.org/wiki/Category:Protostomes https://en.wikipedia.org/wiki/Protostome https://eol.org/pages/10459935 https://species.wikimedia.org/wiki/Protostomia https://www.wikidata.org/wiki/Q5171 A clade of animals. Together with the deuterostomes and xenacoelomorpha, its members 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 and is based on the embryological origins of the mouth and anus. Protostomia protostomes