Noasaurines form an enigmatic group of small-bodied predatory theropod dinosaurs known from the Late Cretaceous of Gondwana. They are relatively rare, with notable records in Argentina and Madagascar, and possible remains reported for Brazil, India, and continental Africa. In south-central Brazil, the deposits of the Bauru Basin have yielded a rich tetrapod fauna, which is concentrated in the Bauru Group. The mainly aeolian deposits of the Caiuá Group, on the contrary, bear a scarce fossil record composed only of lizards, turtles, and pterosaurs. Here, we describe the first dinosaur of the Caiuá Group, which also represents the best-preserved theropod of the entire Bauru Basin known to date. The recovered skeletal parts (vertebrae, girdles, limbs, and scarce cranial elements) show that the new taxon was just over 1 m long, with a unique anatomy among theropods. The shafts of its metatarsals II and IV are very lateromedially compressed, as are the blade-like ungual phalanges of the respective digits. This implies that the new taxon could have been functionally monodactyl, with a main central weight-bearing digit, flanked by neighbouring elements positioned very close to digit III or even held free of the ground. Such anatomical adaptation is formerly unrecorded among archosaurs, but has been previously inferred from footprints of the same stratigraphic unit that yielded the new dinosaur. A phylogenetic analysis nests the new taxon within the Noasaurinae clade, which is unresolved because of the multiple alternative positions that
Noasaurus leali
can acquire in the optimal trees. The exclusion of the latter form results in positioning the new dinosaur as the sister-taxon of the Argentinean
Velocisaurus unicus
.
Over the last few decades, the systematics and evolution of carcharodontosaurids, a group of large predatory dinosaurs, from North Africa have been better understood mainly due the discovery of new species. We review this record here and discuss its importance for understanding the evolution and ecology of these dinosaurs. North Africa has one of the best records of carcharodontosaurid species. These species show dietary specializations and paleogeographic distributions similar to other top predatory theropods such as Abelisauridae and Spinosauridae. However, carcharodontosaurids have a wider distribution than other large theropods. The middle Cretaceous of North Africa was characterized by the niche overlap between large predators. This evidence increases our understanding of the evolution of Carcharodontosauridae in a highly competitive region, a conjuncture rarely reported for large top predators.
The southern Goiás state region of Central Brazil has an extensive and informative record of fossil biota. Particularly over the last five years, there has been a great increase in fossil finds, which has enabled a greater understanding of this region's fauna and flora during the Late Cretaceous. In this article, we provide an updated synthesis of the biota from the Cretaceous of the southern Goiás state, the record of plants, gastropods, turtles, crocodilians, titanosaurs, and theropod dinosaurs.
Titanosaurs are one of the most common dinosaurs found in Cretaceous outcrops, especially in Brazil. In this article we describe a proximal portion of an ulna (Paleo-UFG/V-0039) which was found isolated Paleo-UFG/V-0039 comes from a sandstone outcrop, with fine to medium granulation, of the Marília Formation (Bauru Group) that appears irregularly in the municipality of Gurinhatã, state of Minas Gerais, Brazil. The occurrence described here is the first dinosaur osteological remains documented in this municipality. Although incomplete, Paleo-UFG/V-0039 could be identified as an indeterminate lithostrotian titanosaur whose morphology is similar to some appendicular elements of European species than South American ones. However, the incompleteness of the specimen has difficult complex interpretations. Finally, Paleo-UFG/V-0039 highlights the importance of the Gurinhatã outcrops and other sites in this region for future discoveries.
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