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1 2 Phylum Echinodermata: “spiny skin” - sea stars, brittle stars, sea cucumbers, sea lilies, urchins-

•  General Features –  Exclusively marine –  Benthic herbivores, detritovores,

carnivores; –  All habitats/depths –  Bilateral larvae, radial adult –  Endoskeleton –  Non-centralized nervous system –  Water-vascular system –  Non-segmented –  Well developed digestive system –  Cutaneous respiration –  Regenerative Capacity

3 5 Echinoderm Classes

Cl. Asteroidea Cl. Ophiuroidea

Cl. Echinoidea Cl. Holothuroidea Cl. Crinoidea

4 Figure 33.38 Anatomy of a sea star!

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7 Water Vascular System

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Tube feet

movies

9 Echinoidea

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Aristotle’s lantern

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Sand dollar 12

Ophiuroidea

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14 Crinoids

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Holothuroidea

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Larval Stage