Spinosaur taxonomy and evolution of craniodental features: Evidence from Brazil
A, Premaxillae and maxillae of Baryonyx walkeri. B, Partial rostrum (MNN GDF501) referred to Suchomimus tenerensis. C, Specimen MSNM V4047. D, Reconstructed skull of Irritator challengeri. All specimens are aligned based on the position of the fourth maxillary tooth, whereas the last maxillary tooth (or alveolus) in each is indicated by a black star. Abbreviations for teeth follow Hendrickx et al. . Additional abbreviations: n.c, nasal contact; ao.f, antorbital fenestra; e.n, external naris. A, B, C, and D are modified from Charig and Milner , Sereno et al. , Dal Sasso et al. , and Sues et al. , respectively.