Chitinous exoskeleton is one of the key features to the success of arthropods on land because
The success of arthropods is derived in large part from the evolution of their unique, non-living, organic, jointed exoskeleton. The epicuticle in the exoskeleton contains waxes that aid in reducing evaporative water loss. It is a good terrestrial adaptation to prevent water loss. The exoskeleton provides support, protection and, with the muscle system, contributes to efficient locomotion.