After J.A. Wilson & Sereno, 1998, J.A. Wilson, 2002, and Sereno et al., 2007

<==o †Diplodocoidea Marsh, 1884 sensu J.A. Wilson & Sereno, 1998 and J.A. Wilson, 2002 [Diplodocimorpha Upchurch, 1998]
   |?-o †Amphicoelias Cope, 1877d [not treated by Wilson (2002)]
   |  |-- †A. altus Cope, 1877d
   |  `?- †A. fragillimus Cope, 1878c
   |--o †Haplocanthosaurus Hatcher, 1903b [Haplocanthus Hatcher, 1903a] [paraphyletic Cetiosauridae]
   |  |-- †H. priscus (Hatcher, 1903a) [Haplocanthus priscus Hatcher, 1903a, Haplocanthosaurus utterbacki Hatcher, 1903a]
   |  `-- †H. delfsi McIntosh & Williams, 1988
   `--o Diplodocoidea Marsh, 1884 sensu Upchurch, 1998
      |?- †Amazonsaurus maranhensis de Souza Carvalho, dos Santos Avilla & Salgado, 2003
      |--o †Rebbachisauridae
      |  |?- †Rayososaurus agrioensis Bonaparte, 1996
      |  |-- †Histriasaurus
      |  `--+-- †Rebbachisaurus garasbae Lavocat, 1954
      |     `--+--+-- “Spanish rebbachisaurid”
      |        |  `-- †Nigersaurus taqueti Sereno et al., 1999 [incl. †Rebbachisaurus tamesnensis Lapparent, 1960a]
      |        `--+-- †Zapalasaurus bonapartei Salgado, de Souza Carvalho, & Garrido, 2006
      |           `--+-- †Limaysaurus tessonei (Calvo & Salgado, 1995) Salgado, Garrido, Cocca, S. E. & Cocca, J. R., 2004 [Rebbachisaurus tessonei Calvo & Salgado, 1995; Limaysaurus tessonei Calvo & Salgado, 1995 (nomen nudum)]
      |              `-- †Cathartesaura
      `--o Flagellicaudata Harris & Dodson, 2004
         |-- †Suuwassea emilieae Harris & Dodson, 2004
         |-- †Diplodocidae Marsh, 1884 (diplodokukset, piiskahännät)
         `--o †Dicraeosauridae Janensch, 1929b [Dicraeosaurinae Janensch, 1929b]
            |-- †Amargasaurus cazaui Salgado & Bonaparte, 1991
            `--+-- †Brachytrachelopan mesai Rauhut, Remes, Fechner, Cladera & Puerta, 2005
               `--o †Dicraeosaurus Janensch, 1914
                  |-- †D. hansemanni Janensch, 1914
                  `-- †D. sattleri Janensch, 1914

Note:

The only difference in analysis done by Upchurch (1998) and Wilson (2002) is the position of genus Haplocanthosaurus. In Upchurch's analysis it lies below the Diplodocimorpha-Macronaria dichonomy, i.e. outside of the Neosauropoda.

Wilson places Haplocantosaurus within the Diplodocimorpha [his Diplodocoidea] as the most primitive member of the clade.

Rebbachisaurid phylogeny is based on Sereno et al., 2007

 

Reference(s):