echinoderm
An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as ...
s belonging to the order
Camarodonta
The Camarodonta are an Order (biology), order of globular sea urchins in the class (biology), class Echinoidea. The fossil record shows that camarodonts have been in existence since the Lower Cretaceous.