The crustacean had a normal claw on the left. The other claw on the right side, however, had a third limb growing out from it.
Lobsters usually have two claws – a larger one for crushing and a smaller one for cutting.
According to scientists, though, repetition of body parts can occur in segmented animals such as lobsters and insects, and is not all that uncommon.
Working claws are critical for lobsters to survive and mutants usually die before they can be caught by fishermen.
The Durnfords posted the photo of the lobster to their Facebook page.