There are a few types of crabs in these waters.  These include hermit crabs, porcelain crabs, horseshoe crabs, and true crabs.  This crab would fall into the “true crab” category.  What does that mean?  True crabs have four pairs of walking legs.  This type of crab has a carapace that protects its inner organs (head, thorax, gills, etc).  The size of their abdomen distinguishes the sex of the crab.  Males tend to be larger than females.  Their eyes are on the tip of stalks, and give them a good field of view.  Their first pair of “legs” are actually claws with spikes.  Why do you need claws with spikes?  These guys live in a rough neighborhood.  They need (and frequently use) these claws to ward off predators.  They also use their claws to dig, manipulate items, and crack open shells.  In this case, the crab is using his claws to hold dinner.