Sun star (Crossaster papposus).
A Sun star adds a splash of red colour to a background of kelp in a Scottish loch.
This image is published in the BWPA 2014 book and was used on the front cover of BSoUP's In Focus magazine, spring 2009.
Location: Loch Caron, Scotland
Camera Nikon D80, Tokina 10-17 @10mm