| Valvatida | |
|---|---|
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| 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]
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]
According to the World Register of Marine Species, the following families are included in Valvatida: [5]
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish are also known as asteroids due to being in the class Asteroidea. About 1,900 species of starfish live on the seabed in all the world's oceans, from warm, tropical zones to frigid, polar regions. They are found from the intertidal zone down to abyssal depths, at 6,000 m (20,000 ft) below the surface.
The Asterinidae are a large family of sea stars in the order Valvatida.
The Astropectinidae are a family of sea stars in the order Paxillosida. Usually, these starfish live on the seabed and immerse themselves in soft sediment such as sand and mud.
Goniasteridae constitute the largest family of sea stars, included in the order Valvatida. They are mostly deep-dwelling species, but the family also include several colorful shallow tropical species.
Asterina is a genus of asteroideans in the family Asterinidae.
The Forcipulatida are an order of sea stars, containing three families and 49 genera.
Asteropseidae is a family of sea stars. Members of the family have relatively broad discs and five short tapering arms.
Solaster is a genus of sea stars in the family Solasteridae.
The Solasteridae are a family of sea stars.
Solaster dawsoni, the morning sun star, is a species of starfish in the family Solasteridae. It is found on either side of the northern Pacific Ocean. It has two subspecies:
Hippasteria is one of 70 genera of sea stars in the diverse family Goniasteridae.
Poraniidae is a family of starfishes in the order Valvatida.
The Freyellidae are a family of deep-sea-dwelling starfish. It is one of two families in the order Brisingida. The majority of species in this family are found in Antarctic waters and near Australia. Other species have been found near New Zealand and the United States.
Psilaster is a genus of sea stars of the family Astropectinidae.
Evoplosoma is a genus of deep-sea sea star in the family Goniasteridae.
Mediaster is a genus of starfish in the family Goniasteridae. It was circumscribed in 1857 by William Stimpson for M. aequalis, the genus's type species. Its junior synonym is the genus Isaster, which was circumscribed in 1894 by Addison Emery Verrill for the species now known as M. bairdi. Verrill himself synonymized the two genus names in 1899.
Neoferdina cumingi, also known as Cuming's sea star, is a species of starfish in the family Goniasteridae. It is native to the tropical Indo-Pacific region.
Thromidia catalai, sometimes called the heavy starfish, is a species of starfish in the family Mithrodiidae in the order Valvatida. It is native to the Indo-Pacific region. Thromidia catalai is one of the largest and heaviest starfishes in the world. It is reported to weigh as much as 6 kg (13 lb) and have a diameter of 60 to 65 cm. This species was first described by the Australian biologists E. C. Pope and F. W. E. Rowe in 1977, the type locality being New Caledonia.
Asterina hoensonae is a species of pentagonal starfish in the family Asterinidae. The holotype was collected at Cape Agulhas, South Africa.
Lophaster is a genus of starfish within the family Solasteridae.
| Authority control databases: National |
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