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Despite being poorly known from limited skeletal remains as teeth and a few postcranial material, spinosaurid remains have been reported from two different Lower Cretaceous localities in Brazil, wi...

Dromaeosaurids are poorly known in Europe and their fossil records are mostly postcranial remains. To date, the French faunal records of the family Dromaeosauridae include two taxa: Pyroraptor olympius and Variraptor mechinorum. Nevertheless, their taxonomic validity and phylogenetic relationships as dromaeosaurids are controversial. Here, we report a new record of a dromaeosaurid-like pedal ungual from the ‘Grès à Reptiles’ Formation (Campanian-Maastrichtian) of the Upper Cretaceous of southern France. The French specimen was assigned to cf. Dromaeosauridae on the basis of an extensive qualitative analysis. The new specimen has a strongly curved morphology with a tall, narrow cross-section, which is one of the most characteristic anatomical features of the family. Direct comparison reveals that the claw is similar to that of Pyroraptor olympius (MNHN BO001) from a stratigraphically correlated locality.

Theropod tooth crowns are abundant in the Upper Cretaceous (post-Coniacian) continental deposits of the Bauru Group, Brazil. The distribution of anatomical crown features indicates that a variety of carnivorous dinosaurs inhabited the area at that time, which is consistent with fossil records from other parts of Gondwana. More specifically, some authors have attributed several isolated specimens to the Carcharodontosauridae; while this has important implications for palaeobiogeography and paleoecology, other scholars have argued that the clade became extinct during the Turonian. In this study, we conducted discriminant and phylogenetic analyses for 18 crowns putatively assigned to the Carcharodontosauridae. In short, the discriminant analysis suggested that the specimens should be tentatively assigned to the following groups: non-abelisauroid Ceratosauria, Abelisauridae, Neovenatoridae, Dromaeosauridae, and Pantyrannosauria. By contrast, the phylogenetic analysis indicated that all should be assigned to abelisaurid theropods, which is consistent with the theropod osteological records in both Brazil and Argentina. We recommend using a combined approach involving morphometric and phylogenetic tools when identifying isolated teeth, as this may yield more reliable identifications. We also suggest that all previous reports on the presence of post-Turonian carcharodontosaurids in the Bauru Group are invalid, which also corroborates previous work. Our results indicate that abelisaurids from the Bauru Basin were diverse in morphology and activity; that is, many were quite large and/or played important ecological roles. Findings also support the hypothesis that this taxon had a preference for semi-arid environments.

Abelisauridae é uma ampla família de dinossauros do grupo Theropoda, que inclui grandes animais carnívoros extintos bem como as aves dos dias atuais. Sua distribuição é majoritariamente sulista, mas alguns espécimes são oriundos da Europa. As relações filogenéticas dos abelissaurídeos têm se tornado refinadas, mas ainda existem discordâncias quanto ao posicionamento de grupos incluídos na família que merecem atenção. O plano corporal dos abelissaurídeos é conservador entre o grupo, mas apresenta uma grande disparidade morfológica no crânio. Eles também possuem uma tendência a desenvolver estruturas cranianas que variam entre chifres, espessamentos do crânio e coberturas córneas. A variedade de tecido mole craniano associado à estrutura esquelética sugerem que os abelissaurídeos poderiam apresentar comportamentos de marradas de baixo impacto. O registro brasileiro de abelissaurídeos ainda é escasso e são reconhecidas apenas duas espécies em diferentes unidades geológicas. Ainda assim, é possível verificar que a diversidade desse grupo no Brasil foi grande.