American palaeontologist Dale Russell. The American palaeontologist Paul Sereno and colleagues named the new genus and species Suchomimus tenerensis later in 1998, based on more complete fossils from the Elrhaz Formation. In 2002, the German palaeontologist Hans-Dieter Sues and colleagues proposed that Suchomimus tenerensis was similar enough to Baryonyx walkeri to be considered a species within the same genus (as B. tenerensis), and that Suchomimus was identical to Cristatusaurus. Milner concurred that the material from Niger was indistinguishable from Baryonyx in 2003. In a 2004 conference abstract, Hutt and Newberry supported the synonymy based on a large theropod vertebra from the Isle of Wight which they attributed to an animal closely related to Baryonyx and Suchomimus. Later studies have kept Baryonyx and Suchomimus separate, whereas Cristatusaurus has been proposed to be either a nomen dubium or possibly distinct from both. A 2017 review paper by the Brazilian palaeontologist Carlos Roberto A. Candeiro and colleagues stated that this debate was more in the realm of semantics than science, as it is generally agreed that B. walkeri and S. tenerensis are distinct, related species. Barker and colleagues found Suchomimus to be closer related to the British genera Riparovenator and Ceratosuchops than to Baryonyx in 2021. Description Baryonyx is estimated to have been between long, in hip height, and to have weighed between . The fact that elements of the skull and vertebral column of the B. walkeri holotype specimen (NHM R9951) do not appear to have co-ossified (fused) suggests that the individual was not fully grown, and the mature animal may have been much larger (as is the case for some other spinosaurids). On the other hand, the specimen's fused sternum indicates that it may have been mature. Skull The skull of Baryonyx is incompletely known, and much of the middle and hind portions are not preserved. The full length of the skull is estimated to have been long, based on comparison with that of the related genus Suchomimus (which was 20% larger). It was elongated, and the front of the premaxillae formed a long, narrow, and low snout (rostrum) with a smoothly rounded upper surface. The (bony nostrils) were long, low, and placed far back from the snout tip. The front of the snout expanded into a spatulate (spoon-like), "terminal rosette", a shape similar to the rostrum of the modern gharial. The front of the lower margin of the premaxillae was