Atlantic Rock Crab
Cancer irroratus

f22 @ 1/60s, Ektachrome 64 slide film, ASA:64, Nikonos II w 35mm and Nikon close up lens, Oceanic flash

"Cancer irroratus," Wikipedia, the free encyclopedia. Cancer irroratus is a crab in the genus Cancer. It is found from Labrador to South Carolina at depths up to 2,600 ft (790 m), and reaches 133 mm (5.2 in) across the carapace. Cancer irroratus has nine marginal teeth on the front edge of the carapace beside each eye, and reaches a carapace width of 5.25 inches (133 mm). These crabs are similar in color to, and overlap in size with, the Jonah crab, Cancer borealis. The two species can be distinguished by the purplish-brown spots on the carapace of C. irroratus (contrasting with the yellow spots of C. borealis), and by the smooth edges to the teeth on the edge of the carapace (denticulate in C. borealis).
Narragansett Bay, Narragansett, Rhode Island