Viperidae

     Crotalinae - Pitvipers

     1.  Heat-sensitive pit on head 
     2.  Highly keratinized tail tips (Rattlesnakes)
     3.  High majority are viviparous

     Crotalus - Rattlesnakes
          Crotalus atrox
          Crotalus cerastes - Sidewinder
               Crotalus cerastes cerastes
               Crotalus cerastes cercobombus
               Crotalus cerastes laterorepens
          Crotalus mitchellii - Speckled Rattlesnake
               Crotalus mitchellii pyrrhus
               Crotalus mitchellii stephensi
          Crotalus ruber - Red Diamond Rattlesnake
               Crotalus ruber ruber
          Crotalus scutulatus
          Crotalus viridis - Western Rattlesnake
               Crotalus viridis helleri
               Crotalus viridis lutosus
               Crotalus viridis oreganus

• Leptotyphlopidae • Boidae • Viperidae • Colubridae • Elapidae •