Crabs are one of the oldest living species, its ancestors dating back over 400 million years ago. Crabs have even been around about 200 million years before the dinosaurs! There are over 4,500 types of crabs across the globe, and over 850 different species.
Crabs belong to the order Decapoda, which means “ten-footed” in Greek. They have a hard exoskeleton that protects them from predators and a pair of claws that they use for defense, feeding, and communication. Crabs also have a short tail that is usually tucked under their body.
Crabs can live in various habitats, such as the oceans, freshwater, and land. Some crabs are adapted to swim with their paddle-like legs, while others walk or crawl sideways. Some crabs are omnivorous and scavenge for food, while others are predatory or vegetarian. Some crabs even live in symbiosis with other animals, such as mussels, corals, and sea anemones.
Crabs are fascinating creatures that have many unique features and behaviors. Here are some examples of different types of crabs and their characteristics:
Spider crab: This is the largest crab in the world, with a leg span of up to 4 meters (13 feet)2. Spider crabs are slow-moving and often camouflage themselves with seaweeds and sponges on their shells.
Hermit crab: This is a type of crab that does not have a hard shell of its own, but instead uses empty shells of snails or other mollusks as a home. Hermit crabs can switch shells when they grow or find a better one.
Fiddler crab: This is a type of crab that has one greatly enlarged claw that the male uses to attract females and to fight with other males. Fiddler crabs live in burrows on sandy or muddy shores and feed on algae and detritus.
King crab: This is a type of crab that is not a true crab, but belongs to a group called Anomura. King crabs have long legs and a small abdomen that is attached to the thorax. King crabs are highly prized for their meat and can weigh up to 10 kilograms (22 pounds).
Pea crab: This is a type of crab that is very small, only a few millimeters wide. Pea crabs live inside the shells of mussels or other bivalves and share their food. Pea crabs are harmless to their hosts and do not damage them.
Coral-gall crab: This is a type of crab that lives inside the growing tips of certain corals. The female crab irritates the coral so that it forms a protective chamber around her. The male crab visits the female through a small opening and brings her food.
These are just some of the many types of crabs that exist in nature. Crabs are amazing and diverse crustaceans that deserve our respect and admiration.