Valvatida

Valvatida
	Two Valvatida : a Solaster dawsoni attacking a Hippasteria phrygiana
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Asteroidea
Superorder:	Valvatacea
Order:	Valvatida; Perrier, 1884
Families
	see text

The Valvatida are an order of starfish in the class Asteroidea, which contains 695 species in 172 genera in 17 families.^[1]

Description

The order encompasses both tiny species, which are only a few millimetres in diameter, like those in the genus Asterina, and species which can reach up to 75 cm, such as 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 characterize most of the species. Most members of this order have five arms and two rows of tube feet with suckers. Some species have paxillae and in some, the main pedicellariae are clamp-like and recessed into the skeletal plates.^[2] This group includes the cushion star,^[3] and the leather star.^[4]

Families

According to the World Register of Marine Species, the following families are included in Valvatida:^[5]

family Acanthasteridae Gervais, 1841
family Archasteridae Viguier, 1878
family Asterinidae Gray, 1840
family Asterodiscididae Rowe, 1977
family Asteropseidae Hotchkiss & Clark, 1976
family Chaetasteridae Sladen, 1889
family Ganeriidae Sladen, 1889
family Goniasteridae Forbes, 1841
family Leilasteridae Jangoux & Aziz, 1988
family Mithrodiidae Viguier, 1878
family Odontasteridae Verrill, 1899
family Ophidiasteridae Verrill, 1870
family Oreasteridae Fisher, 1911
family Podosphaerasteridae Fujita & Rowe, 2002
family Poraniidae Perrier, 1875
family Solasteridae Viguier, 1878
family Sphaerasteridae Schöndorf, 1906 †

Acanthaster planci, an Acanthasteridae
Archaster typicus, an Archasteridae
Asterina miniata, an Asterinidae
Asterodiscides truncatus, an Asterodiscididae
Dermasterias imbricata, an Asteropseidae
Chaetaster longipes, a Chaetasteridae
Pentagonaster dubeni, a Goniasteridae
Leilaster radians, a Leilasteridae
Mithrodia clavigera, a Mithrodiidae
Odontaster penicillatus, an Odontasteridae
Linckia laevigata, an Ophidiasteridae
Protoreaster lincki, an Oreasteridae
Podosphaeraster gustavei, a Podosphaerasteridae
Porania pulvillus, a Poraniidae
Solaster stimpsoni, a Solasteridae

References

^ Mah, Christopher (2013). "Valvatida". WoRMS. World Register of Marine Species. Retrieved 2014-01-20.
^ Blake, Daniel B. (1981). "A reassessment of the sea-star orders Valvatida and Spinulosida". Journal of Natural History. 15 (3): 375–394. doi:10.1080/00222938100770291.
^ Mah, Christopher (2012). "Culcita (Agassiz, 1836)". WoRMS. World Register of Marine Species. Retrieved 2013-07-06.
^ Mah, Christopher (2012). "Dermasterias imbricata (Grube, 1857)". WoRMS. World Register of Marine Species. Retrieved 2013-07-06.
^ Mah, C., Hansson, H. (2013). Mah CL (ed.). "Valvatida". World Asteroidea database. World Register of Marine Species. Retrieved 2014-01-20.

Burchett M, Dando M, Waller G; SeaLife: A Complete Guide to the Marine Environment; Smithsonian Institution Press, USA; ISBN 1-56098-633-6, 1996.
[1]

[1] Mah, Christopher (2013). "Valvatida". WoRMS. World Register of Marine Species. Retrieved 2014-01-20.

[Blake-2] Blake, Daniel B. (1981). "A reassessment of the sea-star orders Valvatida and Spinulosida". Journal of Natural History. 15 (3): 375–394. doi:10.1080/00222938100770291.

[3] Mah, Christopher (2012). "Culcita (Agassiz, 1836)". WoRMS. World Register of Marine Species. Retrieved 2013-07-06.

[4] Mah, Christopher (2012). "Dermasterias imbricata (Grube, 1857)". WoRMS. World Register of Marine Species. Retrieved 2013-07-06.

[5] Mah, C., Hansson, H. (2013). Mah CL (ed.). "Valvatida". World Asteroidea database. World Register of Marine Species. Retrieved 2014-01-20.

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