Intraskeletal histovariability and skeletochronology in an ornithopod dinosaur from the Maestrazgo Basin (Teruel, Spain)

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

Abstract Ornithopods are an extinct group of dinosaurs that were particularly abundant and diverse in the Cretaceous Iberian Peninsula, whose abundance Maestrazgo Basin has allowed numerous taxa to be identified over last decade. Many these fossil remains still taxonomically indeterminate require a more detailed study on both macroscopic microscopic scale. In this contribution, osteohistological analysis is carried out partial skeleton—composed five incomplete vertebrae, two dorsal ribs, ischium, fibula, tibia—found province Aliaga (Teruel, NE Spain). We progressive slowdown tissue apposition variation type growth marks generated every bone, allowing precise identification ontogenetic stage specimen as subadult individual. The skeletochronological correlation between different elements also suggests reached sexual maturity at around seven years age died nine twelve age. Likewise, usefulness three‐front model proven for first time ornithopod dinosaur, tool analysing histology expressed by bone single inferring their potential. Comparison with other reveals great variability each element shows depending taxon analysed, which prevents us from determining suitable studying skeletochronology any taxon.

Language: Английский

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A giant spinosaurid from the Iberian Peninsula and new data on the Early Cretaceous Iberian non-avian theropod palaeodiversity

Cretaceous Research, Journal Year: 2025, Volume and Issue: unknown, P. 106134 - 106134

Published: March 1, 2025

Language: Английский

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New information on the Hind limb feathering, soft tissues and skeleton of Microraptor (Theropoda: Dromaeosauridae)

BMC Ecology and Evolution, Journal Year: 2025, Volume and Issue: 25(1)

Published: April 24, 2025

Abstract Background Microraptor is known as the most significant example of extended feathering on legs a paravian, both fossil and modern. Its striking difference with paravians contributes to multiple theories function its conspicuous hind limbs. Recent studies tried uncover evolutionary significance, but anatomy has only been described from small number samples. Results Through analysis 16 specimens , including 8 previously undescribed specimens, here we provide new information structure hindwing feathers within revised feather taxonomy, shape which displays all along limb, except pedal digits. Here describe in detail 6 types: metatarsal remiges, long coverts, femoral well first description tibial feathers, anterior coverts minor coverts. Our study BMNHC PH881 STM 5–5, 5–75, 6–62 6–86 partially consistent previous work, key this proximal shift triangular wing portion formed by that outlines joint between tibiotarsus metatarsus. This configuration does not exist any extant or bird, other non-avian paravian so far, underscoring uniqueness . Unlike reconstructions, display an asymmetrical close-vanned remiges. The preserved are posteriorly projected metatarsus vary medioposterior lateroposterior projection feathers. Conclusions overall layers found two elongated asymmetrically vaned linked more reminiscent forewing modern birds than leg fossils taxa. These observations allow us better understand flight, non-flight locomotion hunting strategies iconic ‘four-winged’ dinosaur suggesting had complex behaviour made it adapted arboreal terrestrial habitats.

Language: Английский

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Macroevolutionary patterns in the pelvis, stylopodium and zeugopodium of megalosauroid theropod dinosaurs and their importance for locomotor function

Royal Society Open Science, Journal Year: 2023, Volume and Issue: 10(8)

Published: Aug. 1, 2023

During the Mesozoic, non-avian theropods represented one of most successful clades globally distributed, with a wide diversity forms. An example is clade Megalosauroidea, which included medium- to large-bodied Here, we analyse macroevolution locomotor system in early Theropoda, emphasizing Megalosauroidea. We scored

Language: Английский

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Reconstruction of the pelvic girdle and hindlimb musculature of the early tetanurans Piatnitzkysauridae (Theropoda, Megalosauroidea)

Journal of Anatomy, Journal Year: 2023, Volume and Issue: 244(4), P. 557 - 593

Published: Dec. 1, 2023

Abstract Piatnitzkysauridae were Jurassic theropods that represented the earliest diverging branch of Megalosauroidea, being one lineages to have evolved moderate body size. This clade's typical size and some unusual anatomical features raise questions about locomotor function specializations aid in support; other palaeobiological issues. Biomechanical models simulations can illuminate how extinct animals may moved, but require data as inputs. With a phylogenetic context, osteological evidence, neontological on anatomy, it is possible infer musculature taxa. Here, we reconstructed hindlimb ( Condorraptor , Marshosaurus Piatnitzkysaurus ). We chose this clade for future usage biomechanics, comparisons with myological reconstructions theropods, resulting evolutionary implications our reconstructions; differential preservation affects these inferences, so discuss issues well. considered 32 muscles total: attachments 29 could be inferred based correlates; meanwhile, respectively 21 12 muscles. found great similarity within Piatnitzkysauridae, differences such origin M . ambiens caudofemoralis brevis are present. Similarities evident Aves, division iliofemoralis externus iliotrochantericus caudalis broad depression gastrocnemius pars medialis cnemial crest. Nevertheless, plesiomorphic origins puboischiofemoralis internus 1 around “cuppedicus” fossa ischiotrochantericus medially ischium. As first attempt reconstruct early tetanurans, study allows more complete understanding evolution theropod pelvic appendages.

Language: Английский

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Phylogenetic position of Kinnareemimus khonkaenensis (Dinosauria: Theropoda: Ornithomimosauria) from the Lower Cretaceous of Thailand

Zootaxa, Journal Year: 2024, Volume and Issue: 5448(1), P. 67 - 84

Published: May 9, 2024

A small-bodied ornithomimosaur, Kinnareemimus khonkaenensis Buffetaut, Suteethorn, and Tong 2009, from the Lower Cretaceous Sao Khua Formation of northeastern Thailand was first reported in 1995, then named 2009. It is only report this group Southeast Asia concluded to be a member Ornithomimosauria, more derived than Harpymimus Garudimimus but basal Archaeornithomimus. Since then, few published studies have analyzed phylogenetic position failed find it within clade Ornithomimosauria. Here, analyses for assessing relationships Ornithomimosauria were performed. The results suggested might ornithomimosaur or belongs subclade Deinocheiridae. shares with deinocheirids proximally projected cnemial crest shape fibula proximal view. Its metatarsal III shows subarctometatarsalian condition pinched between II IV visible anterior view proximally, which evolved independently other ornithomimids. However, could also due immaturity incomplete nature animal.

Language: Английский

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Appendicular myology of Skorpiovenator bustingorryi: A first attempt to reconstruct pelvic and hindlimb musculature in an abelisaurid theropod

The Anatomical Record, Journal Year: 2024, Volume and Issue: unknown

Published: July 11, 2024

Abstract We present the pelvic and hindlimb musculature of abelisaurid Skorpiovenator bustingorryi , constituting most comprehensive muscle reconstruction to date in ceratosaur theropods. Using extant phylogenetic bracket method, we reconstructed 39 muscles that can commonly found archosaurs. Through identification bone correlates, recognized thigh including knee extensors, m. iliofibularis flexor tibialis externus mm. caudofemorales puboischiofemorales crus important foot extension flexion (e.g., anterior gastrocnemii ). Also, autopodial intrinsic were whose function involve ( extensor digiti 2–4 ), digitorum brevis superficialis interdigital adduction interosseus dorsalis ) abduction interosseous plantaris abductor 4 Abelisaurids like show a deep pre‐ postacetabular blade ilia enlarged cnemial crests, which would have helped increasing moment arm related hip extension. pedal pronation probably but reduced pronator profundus Despite some gross differences morphology outgroups crocodilian metatarsus avian tarsometatarsus), study allows us hypothesize several . These not be arranged tendinous bundles as Neornithes, rather condition similar crocodilians with layers formed by fleshy bellies on plantar dorsal aspects metatarsus. The is key for future studies concerning biomechanics, integration functional ichnological data.

Language: Английский

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Reassessment of a theropod ilium from the Kem Kem beds of Morocco and the evolution of ilia in Spinosauridae

Cretaceous Research, Journal Year: 2024, Volume and Issue: unknown, P. 106007 - 106007

Published: Sept. 1, 2024

Language: Английский

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New theropod dinosaur remains from the Upper Cretaceous of the Kem Kem Group (Eastern Morocco) clarify spinosaurid morphology

Zoological Journal of the Linnean Society, Journal Year: 2024, Volume and Issue: 202(2)

Published: Oct. 1, 2024

Abstract The Kem Group is a lowermost lithostratigraphic unit from the Upper Cretaceous that extends along border between Algeria and Morocco, in northern region of Africa. This geological has yielded several tetrapod fossils, including well-represented assemblage theropod dinosaurs, after more than eight decades research. Here, we report new occurrences spinosaurid theropods spinosaurine clade by providing anatomical descriptions taxonomic identifications 11 specimens derived Tafilalt Morocco. Among findings, describe cervical vertebra Sigilmassasaurus, addition to cranial, axial, appendicular elements can safely be attributed Spinosaurinae. Moreover, based on unique combination characteristics, also an isolated partial ischium belonging indeterminate carcharodontosaurid. We deliver detailed redescription one most complete snouts known date. Therefore, dinosaurs show considerable diversity, but many questions, especially related diversity spinosaurids general abundance carnivorous this region, remain unclear until materials are discovered made.

Language: Английский

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The appendicular osteology of the Early Jurassic theropod Piatnitzkysaurus floresi and its implications on the morphological disparity of non-coelurosaurian tetanurans

Zoological Journal of the Linnean Society, Journal Year: 2024, Volume and Issue: 203(1)

Published: Dec. 28, 2024

Abstract Piatnitzkysaurus floresi is a theropod dinosaur from the Cañadón Asfalto Formation (Chubut Province, Argentina) and one of few Early Jurassic tetanurans known worldwide. This species two specimens plays key role in our understanding early evolution tetanuran theropods. Nevertheless, published information about its postcranium limited to original description 1980s drawings views. Here, we redescribe detail appendicular skeleton Piatnitzkaysaurus integrate new into phylogenetic morphological disparity analyses focused on non-coelurosaurian tetanurans. Our results agree with recent studies that place Piatnitzkysauridae (including Condorraptor, Marshosaurus, Piatnitzkysaurus, Xuanhanosaurus) as earliest diverging group Allosauroidea within monophyletic Carnosauria (Allosauroidea + Megalosauroidea). Morphological show occupy different morphospace Cretaceous species. Condorraptor are found occupied by Middle Northern Hemisphere, which indicates presence similar body plans for during Early–Middle The improves knowledge

Language: Английский

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