Family: Acrochordidae Bonaparte, 1831 -- wart snakes Family: Aniliidae Stejneger, 1907 -- false coral snakes Family: Anomochilidae Cundall, Wallach and Rossman, 1993 -- dwarf pipe snakes Family: Atractaspididae Günther, 1858 -- African burrowing asps, stiletto snakes Family: Boidae Gray, 1825 -- boas Subfamily: Boinae Gray, 1825 -- boas Subfamily: Erycinae Bonaparte, 1831 -- Old World sand boas Family: Bolyeriidae Hoffstetter, 1946 -- Mauritius snakes Family: Colubridae Oppel, 1811 -- colubrids, typical snakes Subfamily: Homalopsinae Günther, 1864 Subfamily: Natricinae Bonaparte, 1838 Subfamily: Xenodontinae Cope, 1895 Family: Cylindrophiidae Fitzinger, 1843 -- Asian pipe snakes Family: Elapidae F. Boie, 1827 -- cobras, coral snakes, mambas, sea snakes Family: Loxocemidae Cope, 1861 -- Mexican pythons Family: Pythonidae Fitzinger, 1826 -- pythons Family: Tropidophiidae Brongersma, 1951 -- dwarf boas Family: Uropeltidae Müller, 1832 -- pipe snakes, shield-tailed snakes Family: Viperidae Oppel, 1811 -- vipers, pitvipers Subfamily: Azemiopinae Liem, Marx and Rabb, 1971 -- Fae's viper Subfamily: Causinae Cope, 1859 -- night adders Subfamily: Crotalinae Oppel, 1811 -- pitvipers, rattlesnakes Subfamily: Viperinae Oppel, 1811 -- pitless vipers, true vipers Family: Xenopeltidae Bonaparte, 1845 -- sunbeam snakes Family: †Nigerophiidae