The clade Spinosauroidea was defined in 1998 by Paul Sereno as the node clade containing the common ancestor of Spinosaurus and Torvosaurus and all its descendants. Thomas Holtz in 2004 defined a stem clade with the same name containing all species closer to Spinosaurus than to Passer domesticus. Both clades within all probability include the clade Spinosauridae.
The superfamily Spinosauroidea was named in 1915 by Ernst Stromer. It is a younger synonym of Megalosauroidea if Megalosaurus is in the clade Spinosauroidea, which is the case in almost all modern phylogenetic analyses, and it is therefore redundant.
The ICZN holds that even pure clade names (which do not yet have any governing body) should be replaced if having a traditional taxon suffix and being synonyms of ranked taxa at or below the superfamily level. In practice such a replacement has not taken place.
- Family Megalosauridae
- Family Spinosauridae