Why are water striders classified as arthropods?

Water striders are classified as arthropods because of characteristics shared in common with other arthropods. It's important to remember the arthropod phylum (Arthropoda) is a very broad categorization of living things, characterized by jointed limbs, segmented bodies, and a hard exoskeleton. It includes all the insects. Water striders are considered "true bugs" or Hemiptera, along with aphids, shield bugs and leaf-hoppers; their order is classified below Insecta (the insect class).