Crotalus willardi (willardi) | CLASSIFICATION

Kingdom Animalia (animals)
- Eumetazoa (metazoans)
  - Bilateria (bilaterally symmetrical animals)
    - Deuterostomia (deuterostomes)
      - Phylum Chordata (chordates)
        
        Craniata (craniates)
        
        Subphylum Vertebrata (vertebrates)
        
        Superclass Gnathostomata (jawed vertebrates)
        
        Euteleostomi (bony vertebrates)
        
        Class Sarcopterygii (lobe-finned fishes and terrestrial vertebrates)
        
        Tetrapoda (tetrapods)
        
        Amniota (amniotes)
        
        Class Reptilia (turtles, snakes, lizards, and relatives)
        
        Order Squamata
        
        Family Viperidae
        
        Genus Crotalus
        
        Species Crotalus willardi (willardi)
        
        Infraspecies Crotalus willardi amabilis
        
        Infraspecies Crotalus willardi meridionalis
        
        Infraspecies Crotalus willardi obscurus
        
        Infraspecies Crotalus willardi silus
        
        Infraspecies Crotalus willardi willardi