Valvatida
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Sub-order:Granulosina Sub-order:Tumulosina |
Valvatida is an order of sea stars (Asteroidea), which contains 695 species in 165 genera and 14 families. The order encompasses both tiny species, which are only a few milimeters large, like those in the genus Asterina, and sea stars, which can reach up to 75 centimeters like those species in the genus Thromidia. Almost all species in this order have 5 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] 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.
- http://tolweb.org/Asteroidea
