Unaysaurus is a genus of unaysaurid sauropodomorph herbivore dinosaur. Discovered in southern Brazil, in the geopark of Paleorrota, in 1998, and announced in a press conference on Thursday, December 3, 2004, it is one of the oldest dinosaurs known. It is closely related to plateosaurid dinosaurs found in Germany, which indicates that it was relatively easy for species to spread across the giant landmass of the time, the supercontinent of Pangaea.
Procolophon is a genus of lizard-like procolophonid parareptiles that first appeared in the Early Triassic (Induan) of South Africa, Brazil, and Antarctica. It persisted through the Permian–Triassic extinction event, but went extinct in the beginning of the Early Middle Triassic. The type species is P. trigoniceps.
The Santa Maria Formation is a sedimentary rock formation found in Rio Grande do Sul, Brazil. It is primarily Carnian in age, and is notable for its fossils of cynodonts, "rauisuchian" pseudosuchians, and early dinosaurs and other dinosauromorphs, including the herrerasaurid Staurikosaurus, the basal sauropodomorphs Buriolestes and Saturnalia, and the lagerpetid Ixalerpeton. The formation is named after the city of Santa Maria in the central region of Rio Grande do Sul, where outcrops were first studied.
The Caturrita Formation is a rock formation found in Rio Grande do Sul, Brazil. Its sediments were deposited in the Paraná Basin. The formation is from the Upper Triassic and forms part of the Santa Maria Supersequence in the upper section of the Rosário do Sul Group.
Chigutisauridae is an extinct family of large temnospondyl amphibians. The only genera recognized as belonging to Chigutisauridae at the current time are all from Gondwana. Chigutisaurids first appeared during the Early Triassic in Australia. During the Late Triassic they became widely distributed in Gondwana, with fossils found in South Africa, India and South America. Koolasuchus from the Early Cretaceous of Australia represents the youngest known temnospondyl.
Australerpeton is an extinct genus of stereospondylomorph temnospondyl currently believed to belong to the family Rhinesuchidae. When first named in 1998, the genus was placed within the new family Australerpetontidae. However, studies published a few years later questioned the systematics used in the original description and included the genus within Archegosauridae. A study by Dias & Schultz (2003) reassigned Australerpeton to the family Rhinesuchidae within the suborder Stereospondyli based on an earlier evaluation of the family. In this study, the close similarities between Australerpeton and archegosaurids were attributed to convergent evolution as a result of similar semi-aquatic lifestyles. A redescription of the skeleton of this genus was published by Eltink & Langer in 2014, and the skull was redescribed in a follow-up study published by Eltink et al. in 2016. These studies, as well as a 2017 study focusing on rhinesuchids in general, confirmed that Australerpeton was a rhinesuchid rather than an archegosaurid. Fossils of the genus have been found in the Rio do Rasto Formation of Brazil.
Benthosuchus is an extinct genus of temnospondyl amphibian from the Early Triassic of Russia. It was primarily aquatic, living in rivers and lakes. Multiple species are known, with the largest reaching about 2.5 meters in length.
Rhinesuchidae is a family of tetrapods that lived primarily in the Permian period. They belonged to the broad group Temnospondyli, a successful and diverse collection of semiaquatic tetrapods which modern amphibians are probably descended from. Rhinesuchids can be differentiated from other temnospondyls by details of their skulls, most notably the interior structure of their otic notches at the back of the skull. They were among the earliest-diverging members of the Stereospondyli, a subgroup of temnospondyls with flat heads and aquatic habits. Although more advanced stereospondyls evolved to reach worldwide distribution in the Triassic period, rhinesuchids primarily lived in the high-latitude environments of Gondwana during the Guadalupian and Lopingian epochs of the Permian. The taxonomy of this family has been convoluted, with more than twenty species having been named in the past; a 2017 review recognized only eight of them to be valid. While several purported members of this group have been reported to have lived in the Triassic period, most are either dubious or do not belong to the group. However, at least one valid genus of rhinesuchid is known from the early Triassic, a small member known as Broomistega. The most recent formal definition of Rhinesuchidae, advocated by Mariscano et al. (2017) is that of a stem-based clade containing all taxa more closely related to Rhinesuchus whaitsi than to Lydekkerina huxleyi or Peltobatrachus pustulatus. A similar alternate definition is that Rhinesuchidae is a stem-based clade containing all taxa more closely related to Uranocentrodon senekalensis than to Lydekkerina huxleyi, Trematosaurus brauni, or Mastodonsaurus giganteus.
The Sanga do Cabral Formation is an Early Triassic sedimentary rock formation found in Rio Grande do Sul, Brazil.
Lapillopsis is an extinct genus of stereospondyl temnospondyl within the family Lapillopsidae. Fossils belonging to the genus have been found in the Arcadia Formation of Queensland, Australia.
Sangaia is an extinct genus of rhytidosteid temnospondyl from the early Triassic period of Rio Grande do Sul, Brazil. It is known from the holotype UMVT 4302, the left half of a partial skull, a partial palate, from the paratype UMVT 4303, a partial right palatal fragment and from the referred specimens PV 0497 T and MCN PV 2606, skull fragments, recovered from the Sanga do Cabral Formation in the Rośario do Sul Group.
Polesinesuchus is an extinct genus of stagonolepidid aetosaur known from the Late Triassic of southern Brazil. Fossils have been found from the Santa Maria Supersequence of the late Carnian and early Norian stages, making Polesinesuchus one of the oldest aetosaurs. It contains a single species, Polesinesuchus aurelioi, the fifth aetosaur species known from South America to date. Anatomical evidence suggests that Polesinesuchus likely represents a juvenile individual of the contemporary Aetosauroides.
Teyujagua is an extinct genus of small, probably semi-aquatic archosauromorph reptile that lived in Brazil during the Early Triassic period. The genus contains the type and only known species, T. paradoxa. It is known from a well-preserved skull, and probably resembled a crocodile in appearance. It was an intermediary between the primitive archosauromorphs and the more advanced Archosauriformes, revealing the mosaic evolution of how the key features of the archosauriform skull were acquired. Teyujagua also provides additional support for a two-phase model of archosauriform radiation, with an initial diversification in the Permian followed by a second adaptive radiation in the Early Triassic.
Macrocollum is a genus of unaysaurid sauropodomorph dinosaur that lived during the Late Triassic period in what is now Brazil. It is one of the oldest dinosaurs known.
Nhandumirim is a genus of basal sauropodomorph dinosaur from the Carnian age of Late Triassic Brazil. It is currently considered a saturnaliid sauropodomorph. The type and only species, Nhandumirim waldsangae, is known from a single immature specimen including vertebrae, a chevron, pelvic material, and a hindlimb found in the Santa Maria Formation in Rio Grande do Sul.
The Candelária Formation, in other literature also referred to as Candelária Sequence, is a sedimentary formation of the Santa Maria Group in the Paraná Basin in Rio Grande do Sul, southeastern Brazil. The formation dates to the Carnian of the Late Triassic, locally referred to as Tuvalian, from 231.4 to approximately 222 Ma.
Elessaurus is an extinct genus of archosauromorph from the Early Triassic of Brazil. It contains a single species, Elessaurus gondwanoccidens. It possessed a variety of features common to basal archosauromorphs, particularly basal tanystropheids such as Macrocnemus. However, it is uncertain whether Elessaurus was a particularly close relative of tanystropheids, and it might instead be closer to other major archosauromorph clades. The genus name refers to "Elessar", an alternate name of the character Aragorn from J.R.R. Tolkien's Lord of the Rings trilogy.
Rastosuchus is an extinct genus of stereospondyl temnospondyl within the family Rhinesuchidae. It contains one species, Rastosuchus hammeri, found in the Permian Rio do Rasto Formation of Brazil.
Bonacynodon is an extinct genus of cynodonts that lived in what is now southern Brazil during the Triassic period. The genus is monotypic, containing only the type species Bonacynodon schultzi. B. schultzi is known from two specimens, consisting of two partial skulls and some badly preserved parts of the postcranium. Both specimens were recovered from the Pinheiros-Chiniquá Sequence, part of the Santa Maria Supersequence of the Paraná Basin. This sequence preserves a faunal association known as the Dinodontosaurus Assemblage Zone, which contains numerous other species of cynodonts, dicynodonts and reptiles. Bonacynodon was a small, likely insectivorous cynodont, whose length has been estimated at around 30 centimetres (12 in). It can be distinguished from other cynodonts by its large, serrated (saw-like) canine teeth. Together with the genus Probainognathus of Argentina, it made up the family Probainognathidae, one of the earliest-diverging lineages of the clade Probainognathia. It was a fairly close relative of mammals, the only group of cynodonts alive today.
Oryporan is an extinct genus of procolophonid from the Early Triassic Sanga do Cabral Formation of Brazil. The type species is Oryporan insolitus.
