Saurischia Seeley 1887 [Gauthier 1986], nom. cl. inval. see Clade Saurischia Seeley 1888 [Gauthier, Langer, Novas, Bittencourt & Ezcurra 2020]
   †Sauropoda Marsh 1878 [Salgado et al. 1997]
     †Neosauropoda Bonaparte 1986 [Wilson & Sereno 1998]
       †Diplodocoidea Upchurch 1995 [Wilson & Sereno 1998] see Superfamily Diplodocoidea Marsh, 1884
         †Flagellicaudata Harris & Dodson 2004
           †Diplodocidae Marsh 1884 [Sereno 1998] see Family Diplodocidae Marsh, 1884
             1 Genus †Apatosaurus Marsh, 1877
             2.1 Genus †Supersaurus Jensen, 1985
             2.2.1 Genus †Dinheirosaurus Bonaparte & Mateus, 1999
             2.2.2 Genus †Tornieria Sternfeld, 1911
             2.2.3.1 Genus †Barosaurus Marsh, 1890
             2.2.3.2 Genus †Diplodocus Marsh, 1878