Photo copyright Tim Nicholson.
Feather star, Lamprometra sp.
Taken on Middle Reef, Red Sea, Egypt.
Feather stars, or crinoids, are so called because their arms look just like feathers. By day they keep curled up but on night-dives you see these pretty animals in their warm colours, with their feathery arms extended.
Feather stars have a tenacious grip and anchor themselves to coral, seaweed, sponges, etc. They can swim by sweeping their arms up and down, or crawl slowly on the tips of the arms which are bent right over to hold the body away from the sea bed. They spend most of their time though simply anchored in their chosen location, suspension-feeding.
When food is plentiful, with strong currents carrying large amounts of plankton, feather stars will form large groups. They appear to have no particular predators. Look closely and you will often see another animal - such as a shrimp, crab or fish - living with the feather star. For more on feather stars see SCUBA News issue 55.
Further Reading
The Underwater Photographer: Digital and Traditional Techniques, by by Martin Edge, Paperback, 536 pages (2009)