In this article we will discuss about the structure of Sea Lily (Antedon) with the help of a diagram.
1. Commonly known as “sea feather”,“feather star or sea lily” and is found in shallow waters attached to rocks or stones.
2. Body comprises a small central disc and 5 branched radial arms.
3. The central disc has a distinct oral and aboral surface.
4. The oral surface remains dorsal and bears a central multi-radiate mouth and an acentric small anal aperture borne on a papilla.
5. The aboral surface is rough and bears about 5 long and jointed cirri with small ossicles all over serving for attachment.
6. The arms are divided near the base and thus, appear as ten instead of five.
7. Each arm is traversed by an ambulacral groove all along its length and row of opposing pinules along either lateral margin.
8. Along the lateral margins of ambulacral grooves is present a row of small delicate tube feets without suckers.
9. Sexes are separate and development includes a Crinoid larva.