Cnidaria is a phylum of animals containing over 11,000 species of aquatic invertebrates found both in freshwater and marine environments, including jellyfish, hydroids, sea anemones, corals and some o

Medusozoa is a clade in the phylum Cnidaria, and is often considered a subphylum. It includes the classes Hydrozoa, Scyphozoa, Staurozoa and Cubozoa. Medusozoans are distinguished by having a medusa s