Cranial anatomy and phylogenetic affinities of Bolosaurus major, with new information on the unique bolosaurid feeding apparatus and evolution of the impedance‐matching ear

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

Published: July 28, 2024

Abstract Resolving the phylogenetic relationships of early amniotes, in particular stem reptiles, remains a difficult problem. Three‐dimensional morphological analysis well‐preserved stem‐reptile specimens can reveal important anatomical data and clarify regions phylogeny. Here, we present first thorough description unusual Permian reptile Bolosaurus major , including comprehensive bolosaurid braincase. We describe previously obscured details palate, allowing for insight into feeding mechanics. Aspects rostrum, mandible, neurocranium suggest that B. had particularly strong bite. additionally found has surprisingly slender stapes, similar to middle Macroleter poezicus which may enhanced hearing abilities compared other Paleozoic amniotes (e.g., captorhinids). incorporated our new information large matrix (150 OTUs, 590 characters) explore relationship Bolosauridae among reptiles. Our analyses generally recovered paraphyletic “Parareptilia,” diverge after Captorhinidae + Araeoscelidia. also included within smaller (10 27 designed interrelationships all species be monophyletic. While still require further investigation, phylogeny suggests repeated evolution impedance‐matching ears

Language: Английский

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The Shishugou Fauna of the Middle‐Late Jurassic Transition Period in the Junggar Basin of Western China

Acta Geologica Sinica - English Edition, Journal Year: 2022, Volume and Issue: 96(4), P. 1115 - 1135

Published: Aug. 1, 2022

Abstract The Middle–Late Jurassic transition period is a critical for the evolution of terrestrial vertebrates, but global fossil record from this time relatively poor. Shishugou Fauna has recently produced significant remains dinosaurs and other vertebrate groups, some representing earliest known members several dinosaurian groups best‐known specimens their group. These discoveries are our understanding origin lineages. Radiometric dating indicates that fauna aged approximately 159–164 Ma. Comparisons with similarly‐aged faunas such as Shaximiao Yanliao show both taxonomic similarities differences between these indicate Junggar deposits might have preserved most complete Laurasian fauna.

Language: Английский

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Description and phylogenetic relationships of a new species of Torvoneustes (Crocodylomorpha, Thalattosuchia) from the Kimmeridgian of Switzerland

PeerJ, Journal Year: 2023, Volume and Issue: 11, P. e15512 - e15512

Published: July 19, 2023

Metriorhynchids are marine crocodylomorphs found across Jurassic and Lower Cretaceous deposits of Europe Central South America. Despite being one the oldest fossil families named in paleontology, phylogenetic relationships within Metriorhynchidae have been subject to many revisions over past 15 years. Herein, we describe a new metriorhynchid from Kimmeridgian Porrentruy, Switzerland. The material consists relatively complete, disarticulated skeleton preserving pieces skull, including frontal, prefrontals, right postorbital, nasals, maxillae, premaxillae nearly entire mandible, remains axial appendicular such as cervical, dorsal, caudal vertebrae, ribs, left ischium, femur, fibula. This specimen is referred species Torvoneustes jurensis sp. nov. part large-bodied macrophagous tribe Geosaurini. presents unique combination cranial dental characters smooth cranium, frontal shape, acute ziphodont teeth, an enamel ornamentation made numerous apicobasal ridges shifting small forming anastomosed pattern toward apex crown touching carina. description this allows take look at currently proposed evolutionary trends genus provides information on evolution clade.

Language: Английский

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A taxonomic revision and cranial description of Terrestrisuchus gracilis (Archosauria, Crocodylomorpha) from the Upper Triassic of Pant‐y‐Ffynnon Quarry (southern Wales)

Papers in Palaeontology, Journal Year: 2023, Volume and Issue: 9(6)

Published: Nov. 1, 2023

Abstract Non‐crocodyliform crocodylomorphs, formerly referred to the informal group ‘Sphenosuchia’, are earliest known crocodylomorph precursors of extant crocodylians. They therefore crucial for our understanding early crocodylian evolution and origin typical characteristics, such as formation a secondary palate, complex cranial pneumaticity, reinforced braincase. Terrestrisuchus gracilis , from Upper Triassic fissure fill deposits Pant‐y‐Ffynnon in southern Wales, is represented by almost 200 specimens, comprising articulated, partially associated, isolated remains. In this contribution we provide taxonomic revision redescribe its anatomy detail, based part on novel micro‐computed tomography data. The posterior skull region extensively pneumatized indicated, among other features, large pre‐ postcarotid recesses parabasisphenoid, pneumatic cavity articular mandible. contrast, quadrate forms only small, unfused contact with prootic, suggesting that pneumatization postorbital pre‐dated co‐ossification braincase Crocodylomorpha. preserves an ossified basihyal, which represents first occurrence bone non‐avemetatarsalian archosaurs. Finally, show was probably cathemeral (i.e. active range light levels), phylogenetic flexible discriminant analysis relative dimensions sclerotic ring orbit.

Language: Английский

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Skull sinuses precluded extinct crocodile relatives from cetacean-style deep diving as they transitioned from land to sea

Royal Society Open Science, Journal Year: 2024, Volume and Issue: 11(10)

Published: Oct. 1, 2024

During major evolutionary transitions, groups develop radically new body plans and radiate into habitats. A classic example is cetaceans which evolved from terrestrial ancestors to become pelagic swimmers. In doing so, they altered their air-filled sinuses, transitioning some of these spaces allow for fluctuations in air capacity storage via soft tissue borders. Other tetrapods independently underwent land-to-sea but it unclear if similarly changed sinuses. We use computed tomography study sinus changes thalattosuchian crocodylomorphs that transformed land-bound the only known aquatic swimming archosaurs. find braincase sinuses reduced over transition, similar cetaceans, snout counterintuitively expanded, distinct both trends were underpinned by high rates. hypothesize thalattosuchians ill suited deep diving seem have remained large help drain unusual salt glands. Thus, although convergent general terms, subject different constraints shaped transitions water. Thalattosuchians attained a stage less transitional forms cetacean lineage (late protocetid-basilosaurid) did not further specialized ocean life.

Language: Английский

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Dispatches from the age of crocodiles: New discoveries from ancient lineages

The Anatomical Record, Journal Year: 2022, Volume and Issue: 305(10), P. 2343 - 2352

Published: Aug. 1, 2022

Abstract Crocodilians inspire researchers and the public alike with their explosive hunting methodologies, distinct craniofacial dental morphology, resplendent fossil record. This special issue highlights recent advances in biology paleontology of this fascinating lineage vertebrates. The authors volume bring crocodylians extinct ancestors to life using a variety approaches including fieldwork, imaging, 3D modeling, developmental biology, physiological monitoring, dissection, host other comparative methods. Our journey begins early crocodylomorphs from Triassic, carries us through radiation crocodyliforms during rest Mesozoic Era, finally celebrates diversification development extant crocodylians. Crocodyliform science has grown appreciably past few decades. New species genetic evidence continue keep phylogenies our understanding relationships wavering key places tree such as marine thalattosuchians well still living like gharials. application imaging modeling both preserved tissues specimens is now revealing patterns brain lung evolution function, growth strategies, feeding locomotor behaviors across lineage. Comparative anatomical studies are offering new data on genitals, cephalic venous drainage thoracoabdominal pressures. discoveries found here only reveal there far more work be done understand behavior responsible for great suchians crocodylian descendants experienced conquest Tertiary ecosystems.

Language: Английский

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Neurocranial anatomy of Paralligator (Neosuchia: Paralligatoridae) from the Upper Cretaceous of Mongolia

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

Published: Dec. 13, 2024

Abstract Neurocranial features appear to be phylogenetically informative and key in assessing the still contentious relationships within Crocodylomorpha. However, braincases of many non-crocodylian taxa are incompletely studied precluding assessment evolutionary modifications at base Crocodylia. Here, we describe braincase osteology neuroanatomy paralligatorid crocodylomorph Paralligator from Upper Cretaceous Mongolia based on computed tomography (CT)-scanning, segmentation, 3D modelling several specimens. The anatomy brain endocast, nerves, paratympanic pneumatic cavities is consistent with its phylogenetic position close or Eusuchia. shares a suit neuroanatomical basal eusuchians crocodylians reflecting plesiomorphic condition for In addition, differences endocasts between larger-sized individuals Kansajsuchus smaller Shamosuchus ontogenetic changes extant crocodylians. This suggests that members more clade Paralligatoridae crown-group Crocodylia share similar during ontogeny. We also review distribution mesethmoid Crocodylomorpha show presence clades including Dyrosauridae.

Language: Английский

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A new specimen of Hsisosuchus (Mesoeucrocodylia, Crocodyliformes) from the Upper Jurassic of Yunnan, China with implications for the diversity of the ventral trunk shield of osteoderms in the genus

Historical Biology, Journal Year: 2023, Volume and Issue: unknown, P. 1 - 12

Published: Feb. 1, 2023

Hsisosuchus, with three known species, was the most common genus of crocodyliforms in Sichuan Basin during Jurassic. However, overall shape ventral trunk shield osteoderms has not been clarified due to lack complete specimens. A new specimen Hsisosuchus recently recovered from Upper Jurassic Yunnan nearly preserved. This provides an example for first time us understand and way arrangement genus. Compared articulated part preserved two species genus, are different both arrangement, indicating that pattern is constant within Hsisosuchus. With no skull much postcranial skeleton poorly as well corresponding element can be used compare all considered indeterminate awaiting more materials clarify problem.

Language: Английский

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The osteohistology of Orthosuchus stormbergi using synchrotron radiation microcomputed tomography

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

Published: Oct. 27, 2024

Abstract Orthosuchus stormbergi was a small‐bodied crocodyliform, representative of diverse assemblage Early Jurassic, early branching crocodylomorph taxa from the upper Elliot Formation South Africa. The life history these remains poorly understood, with only sparse investigations into their osteohistology, yet species like have potential to inform about macroevolution growth strategies on stem leading crown crocodilians. In order elucidate patterns , we used propagation phase contrast X‐ray synchrotron micro‐computed tomography virtually image osteohistology postcrania two specimens, including multiple elements type (SAM‐PK‐K409), and femur referred specimen (BP/1/4242). total, scanned nine mid‐diaphyseal sections humerus, radius, ulna, radiale, femur, tibia, fibula, rib. We then compared our results osteohistological published literature. Our show that most predominant bone tissue in is lamellar, few patches woven parallel‐fibred bone. contains four five lines arrested hindlimb present outer circumferential lamellae, whereas six seven. Both specimens grew at similar rates, reaching adult skeletal body size year or five. sectioned bones, notably radius are comparatively thick walled compact. virtual one first for an broad sample makes key anchor point understanding plesiomorphic traits clade.

Language: Английский

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Peer Review #1 of "Description and phylogenetic relationships of a new species of Torvoneustes (Crocodylomorpha, Thalattosuchia) from the Kimmeridgian of Switzerland (v0.3)"

Published: July 19, 2023

Metriorhynchids are marine crocodylomorphs found across Jurassic and Lower Cretaceous deposits of Europe Central South America.Despite being one the oldest fossil families named in paleontology, phylogenetic relationships within Metriorhynchidae have been subject to many revisions over past fifteen years.Herein, we describe a new metriorhynchid from Kimmeridgian Porrentruy, Switzerland.The material consists relatively complete, disarticulated skeleton preserving pieces skull, including frontal, prefrontals, right postorbital, nasals, maxillae, premaxillae nearly entire mandible, remains axial appendicular such as cervical, dorsal, caudal vertebrae, ribs, left ischium, femur, fibula.This specimen is referred species Torvoneustes jurensis sp.nov.as part large-bodied macrophagous tribe Geosaurini.Torvoneustes presents unique combination cranial dental characters smooth cranium, frontal shape, acute ziphodont teeth, an enamel ornamentation made numerous apicobasal ridges shifting small forming anastomosed pattern toward apex crown touching carina.The description this allows take look at currently proposed evolutionary trends genus provides information on evolution clade.Thalattosuchia Fraas, 1901 clade mostly that lived Early had near global distribution eastern margins Tethys, opening Atlantic Ocean, down coasts America, China

Language: Английский

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