A feather star with an unusually high arm count - often thirty or more, each finely feathered along its length - spread into a fan or a bowl and held up into the current. Arm span reaches about 25 cm (10 in). Color is wildly variable, from black and maroon through orange and yellow to banded combinations, and gives no help at all in naming the species.
Underneath the arms is a ring of short hooked cirri, and those are the animal's grip: not roots, but claws it uses to walk. A feather star can release, crawl over the reef and even swim, thrashing its arms in alternating sets, which is startling the first time it happens under a torch. Feeding is passive - plankton and particles stick to mucus on tiny side branches and are passed down grooves to the mouth, which sits on the upper surface facing the water rather than the substrate. It works mainly at night, and by day is usually rolled into a ball inside a crevice with only arm tips showing.
- many fine arms, often thirty or more, feathery along their length
- color ranges from black and maroon to yellow and banded
- clings to coral or sponge with short hooked cirri
- arm span up to 25 cm
