Great question as Halloween approaches!
Common spider crabs, or sometimes called mud crabs, are harmless. In fact, their shells are covered with fine short hairs. When you (if you) attempt to pick one up they would actually feel as though their body was covered in felt.
The short little hairs are really what helps the spider crab survive. They help attach pieces of seaweed or other algae species, sponges or barnacles which aid in its main defense mechanism: camouflage.
These common spider crabs are found along the Atlantic coast from Nova Scotia to the Gulf of Mexico.
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