The anatomy of a crustacean
Although crabs and lobsters look different, they share a common physiology. All crustaceans have bilaterally symmetrical bodies covered with a thick exoskeleton.
Like other arthropods, adult crustaceans have segmented bodies and jointed legs. The segments are usually grouped into a recognizable head, thorax, and abdomen. The head bears two pairs of antennae, usually one median eye and two lateral eyes, and three pairs of biting mouthparts – the mandibles and two pairs of maxillae.
This highlights the inherent difficulty in how to humanely kill a crustacean. For instance, many chefs kill shellfish by spiking the ganglia or splittling the animal in half. These methods require speed and precision to minimise suffering. It is easy to miss the ganglia, and the chef has to be careful not to injure himself in the process.
Another widely used method is to boil shellfish alive. Lobsters placed in boiling water take two to three minutes to die. If the gradual heating method is used, they can take 15 minutes to die.
Section of a lobster highlighting
Section of a crab highlighting