Ophidia Brongniart, 1800
   Serpentes see Suborder Serpentes Linnaeus, 1758
     Alethinophidia Nopcsa, 1923 see Infraorder Alethinophidia Nopcsa, 1923
       Henophidia Hoffstetter, 1939 see Parvorder Henophidia Hoffstetter, 1939
         Booidea Gray, 1825
           1 Family Calabariidae Gray, 1858 [monotypic]
           2 Family Boidae Gray, 1825 [paraphyletic?] - pythons and boas
           3 Family Erycidae Bonaparte, 1831
           4 Family Ungaliophiidae McDowell, 1987 see Subfamily Ungaliophiinae McDowell, 1987