My husband took this photo in July 2007 whilst on holiday at Discovery Bay, Jamaica. We were in aprox 10m of water. When we asked Jamaqua Dive Centre what it was, they said the local name for it was 'Lobster Mother'. My husband wondered whether it was some sort of Horseshoe Crab but the instructor said it wasn't. I wrote a review for our local dive club magazine and included it in the write-up asking if anyone could identify it but no one came forward with any suggestions. We would love to know what this is!