Echinoderms (Phylum Echinodermata, from the Greek for spiny skin) are a phylum of marine animals found at all depths. This phylum appeared in the early Cambrian Period and contains about 7,000 living species and 13,000 extinct ones. Five or six classes (six counting Concentricycloidea) are alive today:

• Asteroidea (asteroids, starfish, or sea stars): about 1,500 species that capture prey for their own food.
• Concentricycloidea (sea daisies), notable for their unique water vascular system; two species; recently merged into Asteroidea.
• Crinoidea (crinoids, feather stars or sea lilies): about 600 species that are suspension feeders.
• Echinoidea (echinoids, sea urchins and sand dollars): notable for their movable spines; about 1,000 species.
• Holothuroidea (sea cucumbers): elongated animals resembling slugs; about 1,000 species.
• Ophiuroidea (brittle stars and basket stars), the physically largest of echinoderms; about 1,500 species.

Extinct forms known from fossils include blastoids, edrioasteroids, and several early Cambrian animals such as Helicoplacus, carpoids, Homalozoa, and possibly machaerids.

More on [ Echinoderm ]

Echinodermata - Twitter Search

Porifera coelenterata platythelmintes nemathelmintes annelida mollusca anthropoda echinodermata chordata
nathalichristy (Nathali Christy) Tue, 22 Dec 2009 04:01:01 -0000
Porifera coelenterata platythelmintes nemathelmintes annelida mollusca anthropoda echinodermata chordata
Setau gua echinodermata arthropoda dan vertebrata tp gua ga ngerjainRT @annisayeska: @ovviejunia @aysghaysa @alinnindya ngerangkum bio yg ma
alinnindya (Intan Alinnindya H) Sun, 20 Dec 2009 23:25:46 -0000
Setau gua echinodermata arthropoda dan vertebrata tp gua ga ngerjainRT @annisayeska: @ovviejunia @aysghaysa @alinnindya ngerangkum bio yg ma
@C47 @echinodermata I don't know what to believe anymore Joey.
charlesingram (Charles Ingram) Sat, 19 Dec 2009 11:31:44 -0000
@C47 @echinodermata I don't know what to believe anymore Joey.
@echinodermata @charlesingram I'd be crying right now but I also don't have any tear ducts
C47 (Joey Daoud) Sat, 19 Dec 2009 04:07:25 -0000
@echinodermata @charlesingram I'd be crying right now but I also don't have any tear ducts
@charlesingram @echinodermata it's complicated but yeah, sort of. I would get a major headache forcing my eyes to converge for so long
C47 (Joey Daoud) Sat, 19 Dec 2009 00:19:11 -0000
@charlesingram @echinodermata it's complicated but yeah, sort of. I would get a major headache forcing my eyes to converge for so long
@echinodermata Deep and sober contemplation of the magnificence of the world around us. Oh, we also felt a strong connection to the Earth.
ryanjenkins (Ryan Jenkins) Fri, 18 Dec 2009 18:42:18 -0000
@echinodermata Deep and sober contemplation of the magnificence of the world around us. Oh, we also felt a strong connection to the Earth.

Subscribe to Echinodermata RSS feed