A new species of vocalizing crocodyliform (Notosuchia, Sphagesauridae) from the Late Cretaceous of Brazil.

<italic>Caipirasuchus</italic> is a genus of sphagesaurid notosuchian from the Bauru Basin (Upper Cretaceous), southeast Brazil. They were small-sized herbivorous/omnivorous animals, that measured around 1 metre in length, and had a wide diversity and geographical dispersion in the basin. Here, we diagnosed the 6th species of the <italic>genus</italic>, originating from sandstones of the Adamantina Formation in the municipality of Catanduva, São Paulo State. <italic>Caipirasuchus</italic> presents a significant variation in the morphology of structures in the choana region. In particular, the new species has chambers in the wings of the pterygoids that connect with an extension of the airways, suggesting a region of resonance used in vocalisation. The different palatal structures in <italic>Caipirasuchus</italic> may be related to distinct bioacoustic signatures and indicate apossible improvement in the social organisation of <italic>Caipirasuchus</italic>. [ABSTRACT FROM AUTHOR]