Pascal Kobeh / Atlantic / Common rock crab (Cancer irroratus) on the reef in the middle of green sea urchins (Strongylocentrotus droebachiensis) Gulf of Saint Lawrence, Canada

Pascal Kobeh / Atlantic rock crab or common rock crab (Cancer irroratus) on the reef, Gulf of Saint Lawrence, Canada.

Nick Hawkins / Comparison of the invasive European green crab (Carcinus maenas) on left to native Atlantic rock crab (Carcinus irroratus) on right. Kejimkujik Seaside National Park, Nova Scotia, Canada. July.

Nick Hawkins / Rock crab (Cancer irroratus) off Nova Scotia, Canada. August

Scott Leslie / Atlantic Rock Crab (Cancer irroratus), Bay of Fundy, Maine

MYN / Jerry Monkman / Rock crab (Cancer irroratus) ventral view, Rye, New Hampshire, USA, January. meetyourneighbours.net project

MYN / Jerry Monkman / Rock crab (Cancer irroratus) dorsal view, Rye, New Hampshire. meetyourneighbours.net project

Scott Leslie / Atlantic Rock Crab (Cancer irroratus) hiding in sand, Nova Scotia, Canada

Scott Leslie / Atlantic Rock Crab (Cancer irroratus) on algae, Nova Scotia, Canada

Jeff Rotman / Atlantic Rock Crabs (Cancer irroratus) mating. New England, USA, Atlantic Ocean.

Scott Leslie / Atlantic Rock Crab (Cancer irroratus) and Acadian Hermit Crab (Pagurus acadianus) on kelp, Bay of Fundy, Maine

Joel Sartore / Photo Ark / Atlantic rock crab (Cancer irroratus) portrait, Maine State Aquarium, Maine, USA. Captive.