Commonly called the Jonah Crab this individual was found dead on the beach at the south end of Plum Island. Typically found on rocky shores and bottoms up to 793 meters deep. Range is from Nova Scotia to Florida. Typically about 10 cm long by 15 cm wide. Have 9 teeth on the side of each eye with deep, indented margins between teeth (good for differentiating from rock crab). Carapace is red in color and the underside is yellow. Can commonly be confused with Cancer irroratus, the rock crab (Marine Life of the North Atlantic by Andrew J. Martinez).
The quick movements caught our eyes. We were walking around in low tide. No idea what these tiny critters are.
Not as many as you'd expect on the Ascophyllum, and this is a large one.