| Valvatida | |
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| TwoValvatida : aSolaster dawsoni attacking aHippasteria phrygiana | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Asteroidea |
| Superorder: | Valvatacea |
| Order: | Valvatida Perrier, 1884 |
| Families | |
see text | |
TheValvatida are anorder ofstarfish in theclassAsteroidea, which contains 695species in 172genera in 17families.[1]
The order encompasses both tiny species, which are only a fewmillimetres in diameter, like those in thegenusAsterina, and species which can reach up to 75 cm, such as species in the genusThromidia. Almost all species in this order have five arms withtube feet. This order is primarily identified by the presence of conspicuous marginalossicles, which characterize most of the species. Most members of this order have five arms and two rows of tube feet with suckers. Some species havepaxillae and in some, the mainpedicellariae are clamp-like and recessed into the skeletal plates.[2] This group includes thecushion star,[3] and theleather star.[4]
According to theWorld Register of Marine Species, the following families are included in Valvatida:[5]
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Authority control databases: National |
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