Photo copyright Tim Nicholson, whose underwater photographs and photo books are available from http://www.photoboxgallery.com/timnicholson.
Taken on a night dive in the Egyptian Red Sea.

The body of this soft coral, Alcyonacea order, is stiffened with yellow spicules. Here the individual polyps are open, showing their 8 tentacles (the 8 tentacles help to confirm identification). A member of the Dendronephthya genus, it is partly down to the soft corals that much of the diving in the Red Sea is so beautiful.

More photos of soft corals are in Room five of our gallery
News stories about coral

Further Reading
The Red Sea in Egypt Part II, Invertebrates, by Farid S Atiya, Elias Modern Printing House, 1994, ISBN 977-00-6697-4