Echinoderms

• Echinoderms means "spiky or prickly skinned"
• Echinos - hedgehog
• derma - skin
• Echinoderms was first introduced by Jacob Klein (1734)
• Echinoderms are largely bottom dwellers
• Echinoderms are pentamerous radial symmetry
• Echinoderms have numerous tube feet or podia
• Echinoderms has no definite head or brain
• Echinoderms can regenerate
• Echinoderms has no excretory organs
• Ambulacra - five radiating area
• Inter-ambulacra: five alternating interradii
• Pentaceros are also known as oreanster or sea pentagon
• Pentaceros is very harmful to the pearl industry
• Astropecten are the common starfish
• Ophiothrix is called the common brittle star
• Ophiothrix's arms are covered with fringed with spines
• Ophiothrix can regenerate its arms
• Gorgonocephalus is commonly called as "basket star"
• Gorgonocephalus has much branched arms
• Gorgonocephalus' aboral face is annulated
• Gorgonocephalus' oral surface of each arm is spiny
• Echinus is commonly called as sea urchin
• Asteroidea is commonly known as star fish or sea stars
• Somastoroidea is fossil palaezoic starfish
• Euasteroidea are the living sea stars
• Ophiuroidea is commoly known as brittle stars
• Echinoidea are commonly known as sea urchins
• Holothuroidea are commonly known as sea cucucmbers
• Crinoidea are commonly known as sea lilies
• Carmerata are commonly known as extinct stalk crinoids.
• Vulnerable echinoderms species:

  Collector's urchin

  long-spined sea urchin

  black sea cucumber

  marble sea cucumber
• Asteroidea:

  Somastoroidea

  Euasteroidea
• Echinoidea:

  Bothriocidaroida

  regularia

  irregularia