Biology:Velatida

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Short description: Order of starfishes

Velatida
Starfish at Tafelberg deep DSC09595.JPG
Pteraster capensis
Scientific classification e
Domain: Eukaryota
Kingdom: Animalia
Phylum: Echinodermata
Class: Asteroidea
Order: Velatida
Perrier, 1884
Families

5, see text

The Velatida are an order of sea stars containing about 200 species in five families. These sea stars normally have thick bodies with large discs.[1]

Description and characteristics

This order contains mostly deep or cold seas sea stars, often with a wide distribution (sometimes global). They have a pentagonal or star shape, with between 5 and 15 arms. Their skeleton is weakly developed, which confers them a good flexibility, and numerous papillae on the aboral surface allow them to breathe in poorly oxygenated waters. Their pedicellariae are often provided with spines. The smallest are Caymanostellidae (between 0,5 and 3 cm) and the biggest Pterasteridae (up to 30 cm).[2]

Taxonomy

New molecular evidence now suggests a relationship between some velatid and valvatid families.

List of families according to World Register of Marine Species:[3]

References

Wikidata ☰ Q3277156 entry