Edible crab
The edible crab, also known as the common crab, is a significant species found in the Atlantic Ocean, particularly off the coasts of Britain and Europe, as well as in the Mediterranean Sea. This large crustacean is characterized by a hard, shell-like carapace made of chitin, which protects its soft body. The carapace features a distinctive pie-crust edge, and the crab possesses ten legs, two of which are equipped with powerful pincers used for defense and feeding. Edible crabs are primarily carnivorous, feeding on mollusks by using their claws to pry open shells.
Reproduction occurs shortly after a female molts, during which she carries fertilized eggs until they hatch into larval forms known as zoeae. These larvae undergo several transformations before settling on the ocean floor and developing into adult crabs. Edible crabs typically measure between four and ten inches wide and can weigh up to 11 pounds, with a lifespan that may reach up to 20 years. Their popularity as seafood makes them a staple in various cuisines, highlighting their cultural significance in many regions.
On this Page
Subject Terms
Edible crab
The edible crab's name means that it can be eaten. This species is popular with people throughout its range and is often called the common crab in some countries.
Kingdom: Animalia
Phylum: Crustacea
Class: Malacostraca
Order: Decapoda
Family: Cancridae
Genus: Cancer
Species: Pagurus
The edible crab is a large species that lives in the Atlantic Ocean off the coast of Britain and Europe. It also may be found throughout the Mediterranean Sea. Small edible crabs make their homes under stones on or near shore, while larger crabs live in rocky crevices in shallow waters below the tidal zone.
Like other crabs, the edible crab has a soft body which is protected inside a hard, shell-like covering called a carapace. The carapace functions in a way similar to the carapace of a turtle. The crab's carapace is made of chitin which the crab's body secretes. Chitin also forms plates around the legs, claws, and underside of the crab. Each year a crab molts, or sheds, its carapace. Chitin forms a new soft shell underneath the carapace and quickly hardens into a new carapace to replace the old, smaller, worn carapace. One distinguishing feature of the edible crab is the pie-crust edge of its carapace. The bumpy, indented edges look like the edges of some pie crusts.
The head of the edible crab has two eyes with many lenses. These are called compound eyes. The eyes are located on little stalks which are flexible and which the crab can shorten or stretch. Behind its head is the thorax, or mid-body section. Attached to the thorax are the edible crab's 10 legs. These 10 legs are the reason the crab is in the order Decapoda, which is Latin for 10- legged. Each of the first two legs has a large pincer, or claw, on its tip for defense and for handling food. The edible crab eats mollusks which it seizes and pries open with its powerful pincers. The other four pairs of legs are used for walking. The abdomen is the tail section behind the thorax.
A male mates with the female shortly after she molts, or sheds, her carapace while her new carapace is still soft. After the sperm fertilize the eggs of the female, she carries her eggs along the underside of her body. They stick to her until they hatch into larval crabs weeks later. The larvae are called zoeae, which look like shrimp. The zoeae feed for several weeks on plankton, which are tiny creatures that float in the water. Development of the larvae continues when they change into megalops larvae. Megalops means large eyes, and these young crabs begin to look more like crabs than like shrimp. Megalops larvae descend to the bottom and molt several times as they become adults with fully-developed carapaces and adult habits.
An edible crab is between four and 10 inches (10 and 25 centimeters) wide and weigh up to 11 pounds (5 kilograms).
Edible crabs may live for up to 20 years.
Bibliography
Barfield, P. D. "Notes on the Natural History of the Edible Crab, Cancer Pagurus Linnaeus, 1758." Sea-Nature Studies, www.seanature.co.uk/pmnhs‗cancer‗pagurus.html. Accessed 13 Apr. 2024.
“Cancer Pagurus.” Animalia, www.animalia.bio/cancer-pagurus?environment=1362. Accessed 13 Apr. 2024.
“Edible Crab (Cancer Pagurus).” The Marine Life Information Network, www.marlin.ac.uk/species/detail/1179. Accessed 13 Apr. 2024.
“Edible Crab.” The Wildlife Trusts, www.wildlifetrusts.org/wildlife-explorer/marine/crustaceans/edible-crab. Accessed 13 Apr. 2024.