Valvatida

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Valvatida
Mediaster aequalis
Scientific classification
Kingdom: Animalia Subkingdom: Eumetazoa Phylum: Echinodermata Class: Asteroidea Order: Valvatida Perrier, 1884
Families
See text.

Valvatida is an order of starfish in the class Asteroidea, which contains 695 species in 165 genera in 14 families. The order encompasses both tiny species, which are only a few milimetres in diameter, like those in the genus Asterina, and sea stars, which can reach up to 75 cm like species in the genus Thromidia. Almost all species in this order have five arms with tube feet. This order is primarily identified by the presence of conspicuous marginal ossicles, which often characterize most of the species. Clamp-type pedicellaria are usually being the main type of pedicellaria in this group.

[edit] Families

• Sub-order Granulosina
  • Archasteridae
  • Chaetasteridae
  • Goniasteridae
  • Odontasteridae
  • Ophidiasteridae
  • Oreasteridae
• Sub-order Tumulosina
  • Podosphaerasteridae
  • Sphaerasteridae

Cushion star (Culcita novaeguineae)

Red-knobbed Starfish (Protoreaster linckii)

Granulated sea star (Choriaster granulatus)

Schmedelian pin-cushion sea star (Culcita schmedeliana)

[edit] References

• This article is based on a translation of an article from the German Wikipedia.
• Burchett M, Dando M, Waller G; SeaLife: A Complete Guide to the Marine Environment; Smithsonian Institute Press, USA; ISBN 1-56098-633-6, 1996.
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