Goniasteridae (the biscuit stars) 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.
Goniasteridae are usually middle-sized sea stars with a characteristic double range of marginal plates bordering the disk and arms. Most of them have five arms, often short and triangular, around a broad central disc; many species are pentagonal or subpentagonal, covered densely with granular, seed-like protuberances, hence the name of the family "seed-star" (gonium+aster). The aboral face is often covered with tiny spines looking like paxillae. Pedicellariae are often valvate, and the gonads are located at the interradius.[1]
Main identification keys for this group include the presence of paxillae, granules, teeth, spines, or the shape and dimensions of marginal plate.[2]
Location and habitat
They occur predominantly on deep-water continental shelf habitats (but a part of them inhabit shallow waters)[3] in all the world's oceans, being the most diverse in the Indo-Pacific region.[4]
List of genera
About 260 extant species within 70 genera are currently known, which make this family the most diverse of all the sea stars,[5] even if half of the genera are monospecific. Species belonging to the Ferdininae subfamily have been imported from Ophidiasteridae thanks to a large revision of these two families in 2017[6]
.jpg){kind=link}
.jpg){kind=link}
_01.jpg){kind=link}
.jpg){kind=link}
