The subfamily Spinosaurinae was named by Sereno in 1998, and defined by Thomas Holtz and colleagues in 2004 as all taxa closer to "Spinosaurus aegyptiacus" than to "Baryonyx walkeri". The subfamily Baryonychinae was named by Charig & Milner in 1986. They erected both the subfamily and the family Baryonychidae for the newly discovered "Baryonyx", before it was referred to the Spinosauridae. Their subfamily was defined by Holtz and colleagues in 2004, as the complementary clade of all taxa closer to "Baryonyx walkeri" than to "Spinosaurus aegyptiacus". Examinations in 2017 by Marcos Sales and Cesar Schultz indicate that the South American spinosaurids "Angaturama" and "Irritator" were intermediate between Baronychinae and Spinosaurinae based on their craniodental features and cladistic analysis. This indicates that Baryonychinae may in fact be non-monophyletic. Their cladogram can be seen below.