The brain endocasts of the late Triassic (Carnian) traversodontids (Eucynodontia: Gomphodontia) Siriusgnathus niemeyerorum and Exaeretodon riograndensis from southern Brazil are described based on virtual models generated using computed tomography scan data. Their skull anatomy resembles that of other nonmammaliaform cynodonts, showing an endocranial cavity that is not fully ossified. A "V-shaped" orbitosphenoid, neither fully developed nor ossified is present in E. riograndensis. The nasal cavity is confluent with the encephalic cavity. Thus, the anterior limit of the olfactory bulbs is not definite. The brain endocast is elongated, being narrow anteriorly and wide posteriorly, with the maximum width at the parafloccular cast. The olfactory bulbs do not present a clear division between their counterparts, due to the absence of a longitudinal sulcus. A longitudinal sulcus in the forebrain delimiting the cerebral hemispheres, the pineal tube, and the parietal foramen are absent in both taxa. The large and well-developed unossified zone is partially separated from the remaining endocast by a notch formed by the supraoccipital. The encephalization quotients, as well as the endocranial volume/body mass relationships of S. niemeyerorum and E. riograndensis are within the range expected for nonmammaliaform Therapsida.

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A new fossiliferous site from the Pinheiros-Chiniquá Sequence (Santa Maria Supersequence) with typical tetrapod components of the Dinodontosaurus Assemblage Zone (AZ) is here described. The new site is included in the Faxinal do Soturno Structural Block. The fossil content is characterized by cranial and postcranial material of rauisuchian archosaurs, traversodontid and chiniquodontid cynodonts and dicynodonts, the first occurrence of a large-sized coelacanth fish in the Brazilian Triassic, as well as ichnological material, represented by coprolites. The presence of Luangwa together with Massetognathus raises interesting questions regarding the age of this site included in the Dinodontosaurus AZ when compared with other localities of Southern Brazil, western Argentina and Africa. As in other localities of this AZ, the fossil specimens recovered in Bortolin site exhibit remarkable differences on their fossil preservation: those from the lower portion of the outcrop (distal floodplain) possess a heterogeneous preservation (variable between poor to fairly good) whereas those from the top levels (proximal floodplain) are comparatively better preserved. This new locality, with a large amount of stratigraphically controlled fossils, constitutes a key-locality to study the distribution of Triassic terrestrial tetrapods and to perform comparisons with other sites of this AZ, in which several historical records lack a precise provenance.

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