How Is A Crab Adapted To The Seashore?

A crab is a decapod crustacean. In other words, it is a crustacean that has ten legs (or five pairs of legs). It belongs to the infraorder Brachyura. Brachyura is an infraorder which is typically characterised by a short tail. The word Brachyura is, in fact, derived from the two words Brachy, which is the Greek word for short, and ura, which is the Greek word for a tail.

The abdomen of a crab is usually hidden under the thorax and covered with a thick exoskeleton. Crabs generally have two claws (which are known as chelae) on each leg. The first pair of legs is a modified claw and is not used for locomotion. The abdomens of some species of crabs are folded under their cephalothoraxes. They have flattened maxillipeds which cover their mouthparts. There is no long rostrum at the front of the carapace of a crab. The gills of crabs are in the form of flattened plates called phyllobranchiates.