bubble updated Sand Sifting Sea Star
2013-03-06 07:05:13 -0500
Astropecten polyacanthus, the **sand sifting starfish** or **comb star**, is a sea star of the family Astropectinidae. It is the most widespread species in the Astropecten genus, found throughout the Indo-Pacific region. The armspread is up to 20 cm (8 in). The specific epithet "polyacanthus" comes from the Latin meaning "many thorned". The tube feet are pointed rather than having suckers, an arrangement that is more suitable for digging. Astropecten polyacanthus can be confused with Archaster spp. which look similar because both have developed features to enable them to dig through sand through convergent evolution. Archaster has spines that are flat and blunt and on its upper surface has parallel, radial rows of plates while Astropecten polyacanthus does not. Distribution The comb star is found in shallow tropical and sub-tropical seas throughout the Indo-Pacific region from the Red Sea and Zanzibar to Hawaii, and from Japan to Australia and New Zealand.