Does a Arizona bark scorpian have back bone?

No, the Arizona bark scorpion does not have a backbone. Scorpions, along with spiders, insects, and other arthropods, belong to the phylum Arthropoda, which is characterized by the presence of an exoskeleton, jointed appendages, and a segmented body. Instead of a backbone, scorpions have a hard external skeleton and a flexible segmented body supported by internal fluid pressure.