The Comb Seastar (Astropecten polyacanthus) is the most wide spread species in the Astropecten genus. It belongs to the seastar family Astropectinidae. This species is distributed through out the Indo-Pacific region and its range extends from the Red Sea and Zanzibar across to Hawaii, into the waters of Japan and down to New Zealand. It is primarily a tropical species that can also be found in temperate waters. In Australia it is recorded from Cape Naturaliste in Western Australia around the north to Sydney in New South Wales. This species a lot of time buried below sandy silty bottoms in inshore coastal estuaries and harbours. It can be found from 0 to 40 metres and is known to feed on molluscs. This species is best recognised by the dark purple upper surface and the orange colour underneath.
The Comb Seastar (Astropecten polyacanthus) has a maximum arm radius of approximately 9cm.