Train passengers were left shell-shocked after discovering a live crab – sitting in his own seatThe crabby commuter – who has been named Craig – was found on Wednesday evening on a South Western Railway service from London to Portsmouth. Train driver Mark Walsh was approached by a passenger about the crustacean and at first thought it was a joke – until he saw the seat pincher. Mark says that Craig was quite poorly from the journey, but they dropped him off at a park with a pond in Southsea. The driver speculated that the crab might have escaped from a fisherman’s box or have been placed as a prank by schoolchildren. South Western Railway posted about the incident on Facebook, writing: “Unusual customer alert.