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Buriolestes is a genus of early sauropodomorpha from the Late Triassic Santa Maria Formation of the Paraná Basin in southern Brazil. It contains a single species, B. schultzi, named in 2016. The type specimen was found alongside a specimen of the lagerpetidae dinosauromorpha Ixalerpeton.
Additional remains were discovered in 2015 and published in 2018. These include a mostly complete skeleton, CAPPA/UFSM 0035, which preserves a complete skull and most bones apart from tail vertebrae. Additional dinosaur bones from the Buriol locality may also belong to Buriolestes, but their assignment is uncertain. They include a femur (ULBRA-PVT289), a portion of an individual's hip and hindlimbs (ULBRA-PVT056), and a lone axis vertebra (CAPPA/UFSM 0179). These new finds have made Buriolestes among the most complete Triassic dinosaurs known, comparable to Eoraptor, Herrerasaurus, and Coelophysis.
In 2016, the holotype specimen was described and given the generic name Buriolestes, after the Buriol family; the suffix -lestes is Greek for "robber." The specific name honors palaeontologist Cezar Schultz. The well-preserved additional specimens were described in 2018, with the braincase of CAPPA/UFSM 0035 being described in more detail in 2020.
In Buriolestes, the shaft of the pubis is straight, in contrast to later sauropodomorphs, where it has been modified into an expanded "apron", theropods, where it forms a "boot," and all , where it is reversed and is parallel to the ischium. Additional traits differentiate Buriolestes from both later and contemporary sauropodomorphs: the front expansion (preacetabular ala) of the ilium is relatively tall, the outer edges of the pubis are bevelled, the trochanter of the femur forms a shelf, and the metatarsal bones of the fifth digit on the foot is relatively long.
Skeletally mature specimens of Buriolestes exhibit intraspecific variation through size disparity, with one robust individual weighing over and others weighing between . This robust specimen is collected from the Piche site, which makes it the first Buriolestes specimen outside the type locality.
A 2020 study by Rodrigo T. Müller et al. that analysed Buriolestes' endocranial anatomy indicated a similar brain morphology to crocodiles. Furthermore, the well-developed optic lobe suggests that Buriolestes was a sight-based predator, as its olfactory bulb was comparatively underdeveloped. The volume of the brain endocast additionally suggests a higher encephalisation quotient than sauropods such as Diplodocus, Nigersaurus, and Brachiosaurus. The well-developed flocculus is similar to Saturnalia, and the authors infer this to be the ancestral condition for sauropodomorpha.
In 2022, Aureliano and colleagues performed a mirco-computed tomography scan on the postcranial skeletons of some of the earliest saurischian dinosaurs that lived during the late Carnian including Gnathovorax with sauropodomorphs Pampadromaeus and Buriolestes, which showed that the invasive air sac system was absent and that their bones were not pneumatised. These results indicate that pneumatisation in archosaur groups (, and ) are not homologous, but are traits that independently evolved at least 3 times.
Five variants of phylogenetic analyses published earlier were used along with the description of the new specimens in 2018. One of these analyses, based on Langer et al. (2017) placed Buriolestes in a clade of early sauropodomorphs, alongside Eoraptor, Panphagia, Pampadromaeus, and Saturnalia. Another analysis, which used the dataset of Buriolestes
The co-occurrence of Buriolestes and Ixalerpeton parallels the simultaneous presence of dinosaurs and non-dinosaur dinosauromorpha at other sites (such as the Ischigualasto and Chinle Formation Formations), suggesting that, after their initial evolutionary radiation, dinosaurs did not rapidly replace their dinosauromorph precursors.
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