The Asterinidae are a large family of sea stars in the order Valvatida.
Description and characteristics These are generally small sea stars, flattened dorsally and bearing very short arms, often giving a pentagonal shape in the body; example: Asterians rubens (except in some species possessing more than five arms). The periphery of the body is thin and formed by indistinct, tiny marginal plates. They are characterized by their aboral face formed by plates shaped like crescents, sometimes giving a "knitted" appearance to the skin.
The abyssal species can be bigger, like those of the genus Anseropoda, which can exceed 45 cm in diameter.
Biology Most of the species are small and relatively cryptic: they are often found hidden under rocks or in crevices, for example. Several species have access to a fissiparous asexual reproduction, multiplying their reproductive potential. For that reason, some species of the genera Meridiastra and Aquilonastra can sometimes appear spontaneously in aquariums, where they can proliferate from just one larva imported inadvertently. Some species can brood their young (which thus do not pass through a planctonic larval stage), such as Asterina pancerii.
Most of the species feed on food fragments and algal or bacterial mat covering the substratum, evaginating their stomach on their food (a frequent feeding mode in sea stars). However, some species like Stegnaster inflatus takes advantage of their webbed shape to form a "trap" by heightening on the tip of their arms, and suddenly falling on a prey which would have believed to find shelter there.
They can be found in almost all the seas of the world, from the abysses to the surface and from the poles to the tropics.
Genera This family comprises about 21 genera and 116 species according to O'Loughlin & Waters (2004), whereas the World Asteroidea Database states that it includes 150 species in 25 genera.
Genera included in the family according to the World Asteroidea Database: Ailsastra O'Loughlin & Rowe, 2005 Allopatiria Verrill, 1913 Anseropoda Nardo, 1834 Aquilonastra O'Loughlin in O'Loughlin & Waters, 2004 Asterina Nardo, 1834 Asterinides Verrill, 1913 Asterinopsis Verrill, 1913 Callopatiria Verrill, 1913 Cryptasterina Dartnall & al. 2003 Disasterina Perrier, 1875 Indianastra O'Loughlin in O'Loughlin & Waters, 2004 Kampylaster Koehler, 1920 Manasterina H.L. Clark, 1938 Meridiastra O'Loughlin, 2002 Nepanthia Gray, 1840 Paranepanthia Fisher, 1917 Parvulastra O'Loughlin in O'Loughlin & Waters, 2004 Patiria Gray, 1840 Patiriella Verrill, 1913 Pseudasterina Aziz & Jangoux, 1985 Pseudonepanthia A.H. Clark, 1916 Pseudopatiria O'Loughlin in O'Loughlin & Waters, 2004 Stegnaster Sladen, 1889 Tegulaster Livingstone, 1933 Tremaster Verrill, 1880 Ctenaster L. Agassiz, 1836 Desmopatiria Verrill, 1913
References
Bibliography
External links