A new crocodyliform, Sahitisuchus fluminensis gen. et sp. nov., is described based on a complete skull, lower jaw and anterior cervical vertebrae collected in the São José de Itaboraí Basin of Rio de Janeiro, Brazil. The specimen is one of the best preserved crocodyliforms from Paleocene deposits recovered so far and represents a sebecosuchian, one of the few clades that survived the Cretaceous-Paleogene biotic crisis. The new taxon is found in the same deposit as an alligatoroid, a group that experienced large diversification in the Paleogene. The sebecosuchian record suggests that after the Cretaceous-Paleogene biotic crisis, the less specialized members of this clade characterized by a higher number of teeth compared to the baurusuchid sebecosuchians survived, some having terrestrial habits while others developed a semi-aquatic life style (e.g., Lorosuchus). Starting in the Eocene, sebecid sebecosuchians became specialized with a more accentuated oreinirostry as observed in Sebecus and in Langstonia, but not showing the typical reduced dentition developed by the Cretaceous baurusuchid sebecosuchians. The basal position of Barinasuchus arveloi, a high-snouted Miocene sebecid, indicates the occurrence of an independent lineage sometime after the K-Pg biotic crisis that developed accentuated oreinirostry, suggesting a more complex history of the post-K-Pg crocodyliform radiation.

A new small species of Eocaiman is described on the basis of three anterior left mandibular rami and one isolated tooth. The specimens came from the middle-upper Paleocene Itaboraı ´Basin (Rio de Janeiro State, Brazil; Itaboraian South American Land Mammal Age). The new taxon differs from the other two Eocaiman species, such as its small size, likely participation of the splenial in the mandibular symphysis, a reduced angle between the longitudinal axis of the symphysis and the mandibular ramus, and enlarged ninth and tenth dentary teeth (in addition to the large first and fourth dentary teeth). The participation of the splenial in the mandibular symphysis is a unique character among caimanines (with the only possible exception being Tsoabichi greenriverensis). The new taxon provides new information on the taxonomic and anatomical diversity of the genus Eocaiman, a taxon of prime importance to understand the evolutionary origins of caimans given its position as the basalmost member of Caimaninae. Furthermore, the new taxon has a relatively small body size in comparison with other species of Eocaiman, a case paralleled by other Itaboraian reptilian groups (e.g. snakes), suggesting that this ecosystem provides critical data to test the relationship between reptilian body size and climate. http://zoobank.org/83636F22-D121-4A77-9141-BE68987B6CBF

The Baurusuchidae is one of the most representative families of Crocodyliformes from the Upper Cretaceous of Brazil. Amongst the ten recognized species of the family in the world, eight are recovered from Bauru Basin outcrops. Despite its relative diversity and abundance, information on postcranial elements of species of the family is scarce in the literature. Campinasuchus dinizi is a baurusuchid found in the neocretaceous redstones of the Adamantina Formation of Bauru Basin (SE Brazil). The postcranial skeleton of the species is described based on five specimens, with the following bone elements identified: proatlas, intercentrum of the atlas; pedicles of the atlas; odontoid process; axis; three postaxial cervical vertebrae; nine dorsal vertebrae; eight caudal vertebrae; seven ribs and gastralia fragments; eleven chevrons; twelve osteoderms; pectoral and pelvic girdle; humerus; radius; ulna; manus; femur; tibia; fibula; and pes. Campinasuchus dinizi has the smallest and most delicate postcranial skeleton when compared with examined Baurusuchidae, with an inferred body mass of approximately 28 kg. Some elements of the postcranial skeleton of C. dinizi are also comparatively more robust (e.g. neural spines higher and more developed; vertebral body thicker; pelvic girdle more proeminent; limbs more elongated) than in some notosuchians, such as Mariliasuchus amarali and Notosuchus terrestris, and extant crocodyliforms such as Caiman latirostris and Melanosuchus niger. The mostly straight limbs of C. dinizi indicate a terrestrial habit, and suggests a semi-upright to upright posture during locomotion. The first descriptions of postcranial bones of a young specimen of C. dinizi and osteoderms of Pissarrachampsinae as well as comments about the distinct anatomy of some of those elements are also presented.

A new mesoeucrocodylian (Crocodyliformes) is described from the Laje do Coringa site, earliest Late Cretaceous (early Cenomanian) of the São Luís Basin, northeastern Brazil. Due to the likely hetorodonty indicated by distinct alveoli shapes, Coringasuchus anisodontis gen. et sp. nov. is tentatively referred to the Notosuchia and distinguished from other members of this clade by the presence of obliquely implanted teeth with the main axis directed anterolingually-toposterolabially and the presence of alveoli that are distinctively raised above the level of the dorsal margin of the dentary. The material further confirms the interpretation that the fossil concentration of the Laje do Coringa site is the result of multiple reworking events from previous deposits, but the degree of time-averaging was possibly higher than previously suspected.

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