"We studied many of these on the roots of red mangroves at high tide on this particular afternoon. The carapace on this individual was about 1 to 1-1/4"" wide. They are quite camera shy so I was fortunate to get this image. They almost invariably move/rest on the roots with their head pointing downward towards the water; this image was rotated for a better presentation. I hasten to add that I got this ID from an invaluable reference: Charles Sobczak (2010), Living Sanibel, A Nature Guide to Sanibel & Captiva Islands. This is a superb introduction to a wide array of flora and fauna of the area."