What animals belong to the phylum Cnidaria?

Cnidaria:

1. Cnidaria is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine water.
2. The phylum Cnidaria is also known as Coelenterata.
3. They have radial symmetry.
4. These are diploblastic animals.
5. These have tissue levels of the organisation.
6. Their main characteristic is the presence of cnidoblasts with stinging nematocysts on the tentacles.
7. They also undergo polymorphism and have two body forms, i.e. polyp and medusa.
8. Examples of cnidarians include corals, Hydra, jellyfish, sea anemones, sea pens, sea whips, and sea fans.