Echinoderms are marine animals with pentamerous radial symmetry, an endoskeleton, and tube feet. They include sea stars, sea urchins, sand dollars, sea cucumbers, sea lilies, and feather stars, which are classified into the classes Ophiuroidea, Echinoidea, Holothuroidea, Crinoidea, and Asteroidea. Sea stars have a water vascular system and all echinoderms have tube feet used for locomotion.

1. ECHINODERMS

2. pentamerous
radial
symmetry

3. endoskeleton

4. tube feet

5. Class Ophiuroidea – brittle stars

6. Class Echinoidea – sea urchins and
sand dollars

7. Class Echinoidea – sea urchins and
sand dollars

8. Class Echinoidea – sea urchins and
sand dollars

9. Class Holothuroidea – sea cucumbers

10. Class Holothuroidea – sea cucumbers

11. Class Holothuroidea – sea cucumbers

12. Class Crinoidea –
sea lilies and
feather stars

13. Class Asteroidea – sea stars

14. Class Asteroidea – sea stars

15. Class Asteroidea – sea stars

16. Class Asteroidea – sea stars
water vascular system

17. Class Asteroidea – sea stars

18. Class Asteroidea – sea stars