• It is the spiny brittle star.

• Body consists of small and rounded central disc and 5 long slender arms.

• Body is covered by calcareous and spiny projections.

• Mouth is provided with 5 movable calcareous plates, which act as jaws.

• Bursal slits are seen at the base of each arm.

• On the lower side of the arms, there are small openings called podial pores.

• Digestive system without ceaca, intestine and anus.

• Usually they are mud feeders.

• It has greater power of regenerating its lost arm.

• It is common in the Atlantic west.