Phylum Echinodermata

Echinoderm Examples & Classes

Sea Stars (Asteroidea)

Sea Urchins (Echinoidea)

Sand Dollars (Echinoidea)

Sea Cucumbers (Holothuroidea)

Sea Lily (Crinoidea)

Echinoderm Characteristics Echinoderm

“spiny skinned”

Bilateral Symmetry at Larval Stage

Radial Symmetry as Adults

Benthic

Echinoderm Structure and Function Endoskeleton

Composed of ossicles

Water Vascular System

Locomotion, feeding, gas exchange and excretion

Tracing Water Movement Water Vascular System

Sea Stars Central Disk 5 Arms or Rays

Aboral Surface

Oral Surface

Feeding Carnivores or Scavengers

Stomach exits mouth (What does it use to break down food?)

Reproduction Regeneration

Asexual

Sexual Separate sexes broadcast spawning

Sea Stars (Asteroidea)

http://www.sanjuanislandsguide.com/wildlife/images/sea-stars.jpg

http://www.neaq.org/images/SeaStars.jpg

http://www.underwater.com.au/content/8534/sea_star.jpg

Brittle Stars (Ophiuroidea)

http://upload.wikimedia.org/wikipedia/commons/4/4e/Sponge_Brittle_Stars.jpg

http://clem.mscd.edu/~churchcy/BIO3200/outline/animalia/brittle.jpg

http://www.seasky.org/wallpaper/assets/wallpaper_sea/brittle-star-1280.jpg

Basket Stars (Ophiuroidea)

http://hmsc.oregonstate.edu/visitor/sites/default/files/gallerix/albums/4/270/original/cr-basket-star.jpg

http://www.magnergraphix.com/ScubaPics/creaturepix/Basketstar2.JPG

http://www.reefscavengers.com/invertimages/basketstar.jpg

Sea Urchin (Echinoidea) Tube feet project from five pairs of ambulacral areas

Spines (What for?)

Sea Urchin Majority grazers

Teeth – Aristotle’s Lantern

Sea Urchin, Kelp and Sea Otters

How do you think this food chain works?

Other Echinoderms Sea Cucumbers (Holothuroidea)

Interesting Defense (Cuvierian tubules)

Sea Lilies (Crinoidea)

Long Fossil history

Other Echinoderms Sand Dollars

Sea lilies

Starfish

Brittle stars

Sea urchin

Sea cucumber

Ecological Role of Echinoderms Prey of

Some Molluscs Sea Otters Many Spider Crabs Humans Some Fish

Predators of Molluscs Other echinoderms Cnidarians Crustaceans Coral (Crown –of- Thorns Sea Star)

Destroy Kelp Roe sold for $100-150 a pound