Figure 4

Convergence between serrasalmimid and serrasalmid fishes. (a,b) Comparison between a right prearticular (MHNM KHG 159) of Serrasalmimus secans gen. et sp. nov. (a) and a right dentary of extant Serrasalmus rhombeus (b) from French Guyana (unnumbered specimen from P.-Y. Lebail’s collection, Fish Physiology and Genomics Institute, INRA LGPG, Rennes), in medial view (note that the articular and the angular are still in articulation in the posterior part of the mandible). (c) Phylogenetic relationships between the four genera of serrasalmimid fishes (Pycnodontiformes) (supported by our phylogenetic analysis; see Figs 3 and S4), and convergent evolution with serrasalmid fishes (Characiformes). A congruent series of transformations in dental morphology and arrangement is observed in serrasalmimids and serrasalmids. In both groups, the transition from crushing to cutting dentitions (upper jaws are represented here, with vomerine dentition for serrasalmimids and premaxillary dentition for serrasalmids) is characterized by the successive acquisition of two key features: labiolingually compressed teeth (character 1) and single row of blade-like teeth (character 2). See Supplementary Fig. S7 for further information about the serrasalmid dentitions represented here. Stratigraphic distribution and time-calibrated phylogeny of the serrasalmid genera from refs^22,28. Stage abbreviations are as follows: Aq, Aquitanian; Ba, Bartonian; Bu, Burdigalian; Ca, Campanian; Ce, Cenomanian; Ch, Chattian; Co, Coniacian; Da, Danian; La, Langhian; Lu, Lutetian; Ma, Maastrichtian; Me, Messinian; Pr, Priabonian; Ru, Rupelian; Sa, Santonian; Se, Selandian; Sr, Serravalian; Th, Thanetian; To, Tortonian; Tu, Turonian; Yp, Ypresian. Scale bar, 10 mm. (a, photograph by Lilian Cazes – CNRS/MNHN).