The common name to the family member of phylum Echinodermata of marine family is echinoderm. They are usually characterized by a five-fold symmetry, and possess an internal skeleton of calcite plates. They are found at every ocean depth.
The features of all adult echinoderm are:
- They have a five-fold symmetry.
- Body without segmentation.
- Spiny skin.
- Internal skeleton.
- found at every ocean depth.