Echinodermata
From Microcosm Aquarium Explorer
- Crinoid or feather star. Janine Cairns-Michael
- Opioderma sp. brittlestar. Paul Humann
- Fromia sp. sea star or starfish. Janine Cairns-Michael
- Tripneustes gratilla, Sea Eggs. Scott W. Michael
- Colochirus robustus, Yellow Cucumber.
[edit] The Echinoderms
Feather Stars, Sea Stars, Brittle Stars, Sea Urchins, Sea Cucumbers
Number of Living Species: 6,000.
Common Characteristics: Body has pentamerous radial symmetry (five parts around a central axis); internal skeleton of calcareous ossicles that may be flexible, as in sea stars, or fused into a rigid shell (test), as in sea urchins.
Noteworthy Behaviors: Locomotion achieved with the aid of tiny suckerlike pods that are part of a unique vascular system, a complex network of fluid-filled canals and appendages in the body wall.
[edit] Feather Stars
Class Crinoidea (Crinoids, Feather Stars, Sea Lilies): 550 species
[edit] Starfishes
Class Asteroidea (Sea Stars, Starfish): 1,500 species
[edit] Basket Stars and Brittle Stars
Class Ophiuroidea (Basket Stars, Serpent Stars, Brittle Stars): 2,000 species
[edit] Sea Urchins
Class Echinoidea (Sea Urchins, Heart Urchins, Sand Dollars): 950 species
[edit] Sea Cucumbers
Class Holothuroidea (Sea Cucumbers): 900 species
From: Reef Life by Denise Nielsen Tackett