Cranio-mandibular anatomy and reconstruction of Sahitisuchus fluminensis Kellner et al. (Sebecidae, Crocodyliformes), from Paleogene of Rio de Janeiro, Brazil

PINHEIRO, A.E.; POL, D.; LIMA, U.D.; CAMPOS, D.; BERGQVIST, L.P.

Rio de Janeiro

Simposio; X Simposio Brasileiro de Paleontología de Vertebrados; 2016

Sahitisuchus fluminensis is a cenozoic terrestrialized mesoeucrocodylian, related to Sebecus and Bretesuchus, that came from Paleogene of Itaboraí Basin of Rio de Janeiro state (Northeast Brazil). The holotype specimen was recently described based in a partially preserved skull and mandible that were housed in the Rio de Janeiro DNPM fossil collection. However, the original material is not complete, lacking the premaxillae and most of maxillae, nasals, lacrimals, prefrontals and palpebrals; besides the fusion between skull and mandible in an overbite occlusion, hiding the dentary teeth. Here, we redescribed and reconstruct the skull and mandible of Sahitisuchus fluminensis based not only the holotype (aided by CT images) but also by some isolated but well preserved referred materials (including a complete premaxillary pair); being these materials recovered from the same quarry in the 60?s to 80?s years from last century due mining activities for commercial purposes by Portland Mauá Company. Such study provided us rich amount of informations that allow us to make interesting anatomical considerations and so inferences concerning main adductors and depressor head muscles, improving the knowledge about the anatomy and the food habit for this important post cretacic brazilian taxon, who belonged to one of the few ?non-eusuchian? mesoeucrocodylians radiations during the dawn of Cenozoic in South America.