Nudibranch (yellow, black) 13m depth. Reef #2, Great Barrier Reef, Australia.
Dr. Robert Ricker, NOAA/NOS/ORR.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/51647007@N08">NOAA Photo Library</a>: <a rel="nofollow" class="external text" href="https://www.flickr.com/photos/noaaphotolib/5015047440/">rikr0068</a>