Class Reptilia Linnaeus, 1758 - reptiles
   Subclass Lepidosauria Duméril & Bibron, 1839
     Order Squamata Oppel, 1811
       Suborder Ophidia Latreille, 1804
         Superfamily Xenophidia see Superfamily Colubroidea Oppel, 1811
           1 Family Colubridae Oppel, 1811 - colubrids
           2 Family Elapidae Boie, 1827
           3 Family Hydrophiidae Oppel, 1811 - sea snakes see Subfamily Hydrophiinae Oppel, 1811
           4 Family Viperidae Oppel, 1811 - vipers and pit vipers
           5 Family Crotalidae Oppel, 1811 see Subfamily Crotalinae Oppel, 1811