Question: are cnidarians invertebrates or vertebrates?
Answer: Invertebrates are a broad collection of animal groups (they do not belong to a single subphylum like the vertebrates) all of which lack a backbone. Some (not all) of the animal groups that are invertebrates include: Sponges (Phylum Porifera) Jellyfish, hydras, sea anemones, corals (Phylum Cnidaria)