Locomotion in Arthropoda
The Arthropods are characterized by the existence of some special features which can be considered key to their success. These involve a rigid exoskeleton made up of a Chitinous cuticle which resists deformation, metameric segmentation of the body, and jointed appendages build up of a system of levers. The jointed arthropod limb and its associated muscles allow highly complex movements. Besides, the haemocoel has replaced the septate coelomic cavity of the Annelida. The muscular body wall is broken down into distinct, separate muscles. This allows precise and localized contractions. This in turn has greatly reduced dependence on the hydrostatic skeleton for locomotion, increasing efficiency of locomotion.