Serpentes see Suborder Serpentes Linnaeus, 1758
   Alethinophidia Nopcsa, 1923 see Infraorder Alethinophidia Nopcsa, 1923
     Caenophidia Hoffstetter, 1939
       Colubroidea Oppel, 1811
         Family Colubridae Oppel, 1811 - colubrids
           1.1.1 Subfamily Sibynophiinae
           1.1.2 Subfamily Natricinae Bonaparte, 1838 - water snakes
           1.2.1 Subfamily Pseudoxenodontinae
           1.2.2 Subfamily Dipsadinae Guenther, 1858 - American snail-eating snakes
           2.1.1 Subfamily Grayiinae [monotypic]
           2.1.2 Subfamily Calamariinae
           2.2.1 Subfamily Ahaetullinae Figueroa, McKelvy, Grismer, Bell & Lailvaux, 2016
           2.2.2 Subfamily Colubrinae Oppel, 1811