The Major Classes Of Echinoderms

Characteristics Of Sea Lilies And Feather Stars

sea lilies
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  • Also called crinoids.
  • Spines absent.
  • Young attached by "stems" to bottom; adults usually detach from "stem."
  • Have long arms that stretch outward.
  • Arms have long, tentacle like tube feet used to capture food.

Characteristics Of Sea Stars And Brittle Stars

sea star
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  • Also called stellaroids.
  • Spines present.
  • Body is a central disk, with arms that extend radially.
  • Tube feet used for movement in some species (sea stars), but not in others (brittle stars).
  • Brittle stars pursue prey, using their legs rather than tube feet.

Characteristics Of Sea Urchins And Sand Dollars

sea urchin
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  • Also called echinoids.
  • Spines present.
  • Globe- or disk-shaped body; no legs.
  • Tube feet used for movement.

Characteristics Of Sea Cucumbers

sea cucumber
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  • Spines absent.
  • Elongated, soft body; no legs.
  • Tube feet used for movement.
  • Mouth surrounded by branching tentacles used for feeding.

Any other cool pictures out there of Echinoderms?

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