Explain the antedon of echinodermata which belongs to non chordate phyla?

The antedon is also known as the feather star. It occurs in the bottom half of shallow part of sea. It feeds on plankton and debris and has great power of the regeneration and autotomy. Their body has a disc which is cup shaped. It has multiple arms which are slender like. These are divided into two parts with a row of pinnules. The mouth and anus occurs on oral side and the mouth gives rise to ambulacral grooves. They bifurcate and each branch forms a pinnule.