Echinoderms in the phyla which contains only marine animals.
At the larval stages, they have bilateral symmetry whereas adults of the Echinoderm have radial symmetry.
Examples of Echinoderms:starfish, sea cucumbers,sea lilies and sea urchins.
They are present at Ocean depth, not present in freshwater.
In the echinoderms have unique water vascular system as a circulatory system, which helps in the locomotion, nutrient circulation, gaseous exchange, and waste removal.
