echinoderm: Quick Facts

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Facts

Also Known As	Echinodermata

Photos and Videos

A common comet star and a cushion sea star rest on colorful sponges and seagrass in a vibrant Caribbean underwater scene.

firebrick starfish

high Arctic sea star

giant purple sea urchin

sunflower starfish

Two orange, spiny California sea cucumbers (Parastichopus californicus) intertwined on a rocky surface against a dark underwater background.

Red pencil sea urchin (Heterocentrotus trigonarius) with thick, blunt spines sits on a rocky coral reef in clear ocean water off Maui, Hawaii.

Bright orange and purple sea urchin with long spines resting on a seagrass bed in shallow water, Malapascua, Cebu, Philippines.

examine a variety of echinoderm species such as starfish, basket star, sand dollar, and sea cucumber

Observe sea star reproduction, from egg and sperm release and fertilization to development of zooplankton embryos and larvae

watch a starfish's tube feet pry open a mussel's shell and extrude its stomach onto the mussel

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Topics

Asterozoa Blastozoa Echinozoa Crinozoa carpoid Homostelea Diploporita eocrinoid Parablastoidea Paracrinoidea annelid crustacean sponge flatworm cnidarian arthropod mollusk moss animal lamp shells Chordate

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Key People

Alexander Agassiz

Alexander Agassiz

Swiss-born zoologist, oceanographer, and engineer

Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters

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