Echinodermata (5-57 thru 5-61)

1. Echinodermata (5-57 thru 5-61) Classes 1. Astroidea-Sea Stars 2. Ophiuroidea- Brittle Stars, Basket Stars 3. Echinoidea- Sea Urchins & sand dollars 4. Holothuroidea- Sea Cucumbers 5. Crinoidea- Feather Stars, sea Lillies

2. Characteristics • All marine • Water vascular system • Causing tube feet to move • No heart, gills, lungs, brain, or eyes • Attack prey/Defense mechanisms • 5 part Radial symmetry • Aboral (top)/ Oral (Underneath) • nerve net • Nutrients and gases transported in fluid that fills body cavity

3. Pedicellaria • Pincher like organs • Used to pluck objects off of skin • http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artjul00/urchin3.html • Dermal Branchiae • Found on sea stars • Absorb oxygen from water

4. Water Vascular System • Tube Feet • Used for: • Locomotion • Attachment • Sensation • Feeding • Gas exchange

5. Water Vascular System • Water enters WVS through the madreporite. • canals connecting numerous tube feet. • contracting muscles force water into the tube feet • causing them to extend and push against the ground • relaxing to allow the feet to retract.

6. Feeding • carnivorous • sea stars • detritus foragers • sea cucumbers • plantonicfeeders • feather stars and basket stars • mouth on oral surface & anus on aboral surface. • Sea stars can extend stomach out of mouth and engulf and digest prey • Sea cucumbers can eviscerate gut

7. Reproduction • The sexes are separate in most • Many release sperm and egg into water • symmetrical larvae • Asexual reproduction and Regeneration

8. Echinoderm Pelagic planktonic larvae Sea Star Larvae Brittle Star Larvae Sea Urchin Larvae

9. Phylum Echinoderms : Five Classes • Five Classes • 1. Astroidea • Sea Stars • 2. Ophiuroidea • Brittle Stars, Basket Stars • 3. Echinoidea • Sea Urchins, heart urchins, sand dollars • 4. Holothuroidea • Sea Cucumbers • 5. Crinoidea • Feather Stars, sea Lillies

10. 1. Class Asteroidea  • 1500 living species • Usually 5 rays radial symmetry from central disk • Many active carnivores (gastropods & bivalves) • Excessive numbers can harm marine ecosystems • Ability to regenerate entire body from one arm and portion of central disk • Sea Stars

11. Sea stars have a simple eye at the end of each arm. The eye is able to "see" only differences of light and dark, which is useful in detecting movement.

12. Lined Sea star • a dark strip down each of their five arms • they avoid strong light, and often burrow into the sand or mud they live on in order to avoid sunlight.

13. Nine-armed sea star • Tan with gray lines • Radiates into 9 pointed arms • Common in Florida keys & Fl SW coast

14. Cushion • There are 5 arms • short and taper away from the center of the body.  • Tips of the arms often curl upward.  • The underside of the animal is flat, and beige or cream colored. • Cushioned stars range from North Carolina and Bermuda, to the Bahamas. 

15. West Indian cushion • Four Rays • Six Rays • Seven Rays

16. 2. Class Ophiuroidea  • Usually 5 thin, flexible arms radiate from central disk • Most active echinoderm • swift snake-like movements • often hiding under rocks during day; feed on detritus at night • Examples: Brittle Stars, Basket Stars, Serpent Stars • Brittle stars – 2000 species – most numerous

17. Smooth Brittle Star • 5 serpentine arms attached to a central pentagon-shape disk • Green or gay with darker highlights • SW FL & FL keys

18. Angular Brittle Star • The arms bear spines. • Body color is ranging from warm rose, red, orange and crimson to cool shades of blue and purple.  • Range from NC- Bermuda; East FL & Gulf Coast of FL • Found: Estuaries; shallow water

19. 6 arm brittle star • 6 arms • body color is brown to green-brown or gray, • with alternating dark and light banding on the arms.  • The tube feet are bright red • hemoglobin present in the water vascular system • Found: epibenthic • SE of US; most common FL

20. 3. Class Echinoidea  • “without arms” • Calcareous plates fused into shell (test) • Often covered with spines • spines often used for locomotion instead of tube feet • Burrow in sand (day); more active at night • Most feed on detritus or algae • Ex: Sea Urchins, Heart Urchins, & Sand Dollars

21. Purple Sea Urchin • Longer spines & smaller test • Purplish spines are sharp cones above and flattened paddles underneath

22. Long Spined Black Sea Urchin (Diadema) • Extremely long, fragile spines • Contains venom • Typical body color is black (lighter shades have been observed) • Habitat: quieter waters; • Range: Fl through Gulf of Mexico; Caribbean to Brazil

23. Rock Boring Sea Urchin • AKA Red Rock Urchin • Color is usually reddish, shades of red brown/black • Habitat: surf zone of rocky shorelines; limestone rocks or reefs • Range: Bermuda to NC; Caribbean to Brazil

24. Red Heart Urchin hide under sand during day – when discovered, will “jump” out

25. Slate Pencil Sea Urchin found on sea grass beds and reef ruble

26. 5 keyhole Sand Dollar -covered with short spine “fuzz” • Aka Keyhole Urchin • Covered in felt-like coating of fine, brown, moveable spines • Aristotle’s lantern • Chewing apparatus made up of 5 bird-shaped elements • Common throughout Florida

27. 4. Class Holothuroidea • Elongated soft body – no spines • Bilateral symmetry • Skeletal plates are very small and buried under leathery body wall • Some have tentacle-like tube feet around mouth • Mouth in front & anus at rear • Defense mechanisms • Sea Cucumbers

28. Species of Cucumber • Green Striped Cucumber • Florida Sea Cucumber found in shallow sand flats and sea grass beds • Donkey Dung Sea Cucumber inhabit sandy areas around reefs and sea grass beds

29. Sea Cucumber Expelling threads as a defense Mechanism – actually part of the animals gut These threads are toxic &can be quickly Regenerated.

30. 5. Class Crinoids • 600 species • Most ancient class • Mouth face upward (instead of down) • 5 arms radiate from pentagon shaped body • Long feather-like arms • arms branch into 10 or more arms • Short hook like legs called Cirri • Hide in the reef during the day; at night they uncoil & feed • Tube feet used for filter feeding • Feather Stars and Sea Lilies • Sea lilies found in deeper water

31. Golden ChrinoidFeather Starfound on coral reefs