Photo copyright Tim Nicholson.
Taken on Daedalus Reef in the Egyptian Red Sea.
Whip Coral Gorgonian, Leptogorgia sp.

Whip corals consist of long, cylindrical filaments about the diameter of drinking straws. They are flexible to allow bending in currents. Members of the Octocorallia class they always have 8 tentacles which are pinnate - that is, they possess side branches like a feather.