English name: Scientific name: Familia: Classis: Phylum: Regnum: Animalia
Embryology.The protostomia (= first mouth) develops from the first opening into the gut (blastopore). The body coelom (= cavity) forms from a split (schizo) in the embryonic mesoderm (middle tissue). The group of animals belonging to the Protostomia are: molluscs, arthropods and annelids.