Key Difference – Coelenterates vs Platyhelminthes Kingdom Animalia is divided into two main categories as vertebrates and invertebrates. Invertebrates are further divided into phyla out of which the two most primitive phyla are the Phylum Coelenterate and Phylum Platyhelminthes. Phylum Coelenterata, also referred to as Cnidaria, is the most primitive invertebrate type and are […]