FIGURE 1. A map of the Brazilian state of Acre modified from Hsiou (2010) and Lopes (2016), with the red stars indicating the respective approximate localities in which were collected the holotype of M. amazonensis (near the city of Marechal Thaumaturgo) and the specimens UFAC-1424 and LACM-160157 (the Niteroi Site, near the city of Rio Branco).

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FIGURE 2. Skull of the holotype of Mourasuchus amazonensis (DGM 526-R) in ventral view with schematic drawing. Abbreviations: ect, ectopterygoid; f, frontal; if, incisive foramen; itf, infratemporal fenestra; j, jugal; m, maxilla; o, orbit; pal, palatine; pfo, palatine fossa; pm, premaxilla; po, postorbital; pt, pretygoid; q, quadrate; qj, quadatojugal. Scale equals 20 cm.

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FIGURE 3. Premaxillae of the holotype of Mourasuchus amazonensis (DGM 526-R) in ventral view. Abbreviations: if, incisive foramen; of, occlusal fossa. Scale equals 10 cm.

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FIGURE 4. Posterior portion of the skull of the holotype of Mourasuchus amazonensis (DGM 526-R) in ventral view. Abbreviations: itf, infratemporal fenestra; llEc, left lateral Eustachian canal; mEc, median Eustachian canal; o, orbit; rlEc, right lateral Eustachian canal.

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FIGURE 5. Anterior portion of the left mandibular ramus of the holotype of Mourasuchus amazonensis (DGM 526-R) in dorsal (1), medial (2) and lateral (3) views. Scale equals 5 cm.

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FIGURE 6. Posterior portion of the left mandibular ramus of the holotype of Mourasuchus amazonensis (DGM 526-R) in medial (1), dorsal (2) and lateral 93) views. Scale equals 10 cm.

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FIGURE 7. The most complete teeth of the anterior portion of the left mandíbular ramus of the holotype of Mourasuchus amazonensis (DGM 526-R): the first tooth in lingual (1) and labial (2) views, and the eighth and ninth teeth in lingual (3) and labial (4) views. Scale equals 1 cm.

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FIGURE 8. Skull of UFAC-1424 (Mourasuchus cf. M. amazonensis) in dorsal view with schematic drawing. Abbreviations: f, frontal; itf, infratemporal fenestra; j, jugal; p, parietal; pf, prefrontal; po, postorbital; q, quadrate; qj, quadatojugal; so, supraoccipital; sq, squamosal; stf, supratemporal fenestra. Scale equals 10 cm.

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FIGURE 9. Skull of UFAC-1424 (Mourasuchus cf. M. amazonensis) in occipital view with schematic drawing. Abbreviations: ex, exoccipital; ptf, postemporal fenestra; q, quadrate; qj, quadratojugal; so, supraoccipital; sq, squamosal. Scale equals 10 cm.

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FIGURE 10. Posterior portion of the palate of UFAC-1424 (Mourasuchus cf. M. amazonensis) in ventral view. Abbreviations: ect, ectopterygoid; pal, palatine; pfo, palatine fossa; pt, pterygoid. Scale equals 5 cm.

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FIGURE 11. Left mandibular ramus of UFAC-1424 (Mourasuchus cf. M. amazonensis) in dorsal (1), lateral (2) and medial views (3). Abbreviations: d, dentary; sp, splenial. Scale equals 10 cm.

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FIGURE 12. Posterior portion of the left mandible of UFAC-1424 (Mourasuchus cf. M. amazonensis) in lateral view. Abbreviations: ang, angular; emf, external mandibular fenestra; san, surangular. Scale equals 5 cm.

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FIGURE 13. Skull table of UFAC-1424 in left lateral view. Abbreviations:; f, frontal; ootc, otic opening of the tympanic cavity; q, quadrate; sq, squamosal. Scale equals 5 cm.

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FIGURE 14. Posterior portion of the skull of LACM-160157 (Mourasuchus cf. M. amazonensis) in dorsal view with schematic drawing. Abbreviations: f, frontal; p, parietal; po, postorbital; q, quadrate; so, supraoccipital; sq, squamosal; stf, supratemporal fenestra. Scale equals 10 cm.

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FIGURE 15. Posterior portion of the skull of LACM-160157 (Mourasuchus cf. M. amazonensis) in occipital view with schematic drawing. Abbreviations: bo, basioccipital; ex, exoccipital; fm, foramen magnum; oc, occipital condyle; ptf, postemporal fenestra; q, quadrate; qj, quadratojugal; so, supraoccipital; sq, squamosal. Scale equals 10 cm.

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FIGURE 16. Left (1) and right (2) quadratojugals of LACM-160157 (Mourasuchus cf. M. amazonensis) in dorsal view. Scale equals 5 cm.

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FIGURE 17. Left (1) and right (2) jugals of LACM-160157 (Mourasuchus cf. M. amazonensis) in dorsal view. Scale equals 10 cm.

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FIGURE 18. Posterior portion of the palate (pterygoid and ectopterygoids) of LACM-160157 (Mourasuchus cf. M. amazonensis) in ventral view. Abbreviations: ect, ectopterygoid; pt, pterygoid. Scale equals 10 cm.

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FIGURE 19. Right (1) and left (2) palatines of LACM-160157 (Mourasuchus cf. M. amazonensis) in ventral view. Scale equals 10 cm.

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FIGURE 20. Anterolateral portions of the braincase of LACM-160157 in right (1) and left (2) views. Scale equals 5 cm.

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FIGURE 21. Three tentative rostral fragments of LACM-160157 (Mourasuchus cf. M. amazonensis). Scale equals 5 cm.

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