A theropod tooth from the Missão Velha Formation (Late Jurassic-Early Cretaceous) of the Araripe Basin: oldest Brazilian Abelisaurid record

Historical Biology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 11

Published: April 15, 2024

The Missão Velha Formation (Late Jurassic-Early Cretaceous), often referred to as Brejo Santo Formation, is one of the stratigraphic units Araripe Basin, included within Vale do Cariri Group. This locality, characterised by its fluvio-estuarine paleoenvironment, yielded a diverse paleoichthyofauna while terrestrial vertebrate record still poorly known, with single isolated theropod lateral tooth being briefly cited until now. study aims revisit this specimen (UERJ-PMB R008) in order identify it through current quantitative and qualitative methods. analyses were unable properly classify group, indicating paravian, piatnitzkysaurid abelisaurid affinities, most cladistic assigned UERJ-PMB R008 an tooth. was finally due almost straight distal margin, hooked denticles, similarly sized mesial lanceolate cross section irregular enamel texture. assignment represents not only first definitive for also oldest South America, filling part 30-million-year gap between Eoabelisaurus Spectrovenator.

Language: Английский

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Theropod dinosaur diversity of the lower English Wealden: analysis of a tooth‐based fauna from the Wadhurst Clay Formation (Lower Cretaceous: Valanginian) via phylogenetic, discriminant and machine learning methods

Papers in Palaeontology, Journal Year: 2024, Volume and Issue: 10(6)

Published: Nov. 1, 2024

Abstract The Lower Cretaceous Wealden Supergroup of southern England yields a diverse assemblage theropod dinosaurs, its taxa being represented by fragments in addition to some the most informative associated skeletons European Mesozoic. Spinosaurids, neovenatorid allosauroids, tyrannosauroids and dromaeosaurids are among reported clades. However, majority relevant specimens from Barremian Upper Weald Clay Wessex formations, diversity older Berriasian–Valanginian Hastings Group has remained poorly known, fragmentary thus far remaining enigmatic both terms phylogenetic affinities sometimes provenance. A better understanding would be welcome given paucity dinosaurs worldwide. Here, we describe an teeth Valanginian Wadhurst Formation, mostly collected Ashdown Brickworks locality near Bexhill, East Sussex. These were assessed using phylogenetic, discriminant machine learning analyses found include members Spinosauridae, Tyrannosauroidea Dromaeosauridae, others that remain uncertain affinity within Coelurosauria. appear distinct those already known strata: spinosaurid cannot referred Baryonyx or tyrannosauroid Eotyrannus , for example, but have not named new at this time. Combined with other findings our study indicates was comparable younger units, implying ‘characteristic’ components faunas established early deposition famous geological succession.

Language: Английский

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Isolated theropod teeth from the Upper Cretaceous of Goias State (Brazil): northernmost occurrence of Abelisauridae from the Bauru Basin

Journal of South American Earth Sciences, Journal Year: 2024, Volume and Issue: 146, P. 105075 - 105075

Published: Aug. 8, 2024

Language: Английский

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A lost tooth in the jungle: revisiting the sole dinosaurian record from northern Brazil

Anais da Academia Brasileira de Ciências, Journal Year: 2024, Volume and Issue: 96(suppl 1)

Published: Jan. 1, 2024

The record of Mesozoic reptiles in the Northern region Brazil is extremely limited, with only definite occurrence consisting two ziphodont teeth recovered from an oil well core municipality Nova Olinda do Norte, Amazonas state, strata Alter Chão Formation (Cenomanian) Basin. In this study, we aim to reevaluate MCT.R.514 using most recent methodologies available for identification isolated theropod teeth. cladistic analyses as a possible metriacanthosaurid or non carcharodontosaurid allosauroid while LDAs showed affinities between specimen and Abelisauridae, Piatniktzysauridae, Tyrannosauridae. was assigned abelisaurid due its overall morphology that lacked synapomorphies (i.e. spiraling mesial carina, strongly labially displaced distal well-marked mesiolingual longitudinal groove), maintaining homoplastic features both groups irregular enamel texture, lingually biconcave cross section, straight margin). This, together mostly Laurasian distribution Metriacanthosauridae favors assignment parsimonious hypothesis occasion. further expands still scarce "Mid'' Cretaceous clade Brazil.

Language: Английский

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The Northernmost Record of Abelisauridae (Theropoda: Ceratosauria) from the Upper Cretaceous Bauru Basin, Brazil

Published: Jan. 1, 2024

Language: Английский

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Biomechanics and morphological comparisons of the caudal region of titanosaurs from the Cretaceous of Brazil: Paleobiology and paleoecology inferences

Journal of Anatomy, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 8, 2024

Abstract Biomechanical studies in sauropod dinosaurs are mainly focused on neck posture and feeding strategy. Few works investigate other aspects such as tail movement function, especially the clade Titanosauria, most diverse within Neosauropoda. This study applied biomechanical concepts of neutral pose (cartilaginous pose) range motion to verify shape direction caudal region advanced titanosaurs Adamantisaurus mezzalirai Baurutitan britoi , addition comparing it with (e.g., Arrudatitan maximus Lirainosaurus astibiae Trigonosaurus pricei ). As a result, tails analyzed have sigmoidal‐convex shape, probably close ground (but not touching it). The could increase moment arm for M. caudofemoralis longus making possible use fifth stabilizing member. work expands our knowledge about by exposing diversity shapes titanosaur sauropods brings new possibilities how these their tails.

Language: Английский

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First dinosaur ichnofauna from the Bauru Group indicates Cenomanian–Turonian events led to an ‘Ornithischian Hiatus’ in the Upper Cretaceous of Southeast Brazil

Cretaceous Research, Journal Year: 2024, Volume and Issue: unknown, P. 106075 - 106075

Published: Dec. 1, 2024

Language: Английский

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