After a long time of trying to search this elusive sea star, James fulfilled my wish by finding this Galloping sea star (Stellaster equistris) last Sunday during our trip to Semakau.
One of the identifying features of this star is that it has short stumpy spines that are well spaced apart. From far, it is quite well camouflaged and can easily pass off as a juvenile Common sea star (Archaster typicus).
The story of how this star was found is quite interesting. James first found another rare star, the Eight-armed sea star (Luidia maculata) and he only told me much later about the find. He tried to go back and find the sea star for me to have a look but to no avail. And while searching hard around the vicinity, a rarer star "popped" out and that is this galloping star! Haha!
Therefore, as what Ria later said, everything happens for a reason. :)
It was definitely a fruitful trip and I look forward to come back and explore this part of Semakau more properly. :)
More photos of the trip here: http://www.flickr.com/photos/koksheng/archives/date-taken/2011/08/14/