Migrations, diversifications and extinctions: the evolutionary history of crocodyliforms in Australasia

Alcheringa An Australasian Journal of Palaeontology, Год журнала: 2023, Номер 47(4), С. 370 - 415

Опубликована: Май 22, 2023

Crocodyliform palaeontology in Australasia has a productive research record that began the late nineteenth century and continues today. In this study, we summarize current understanding on taxonomic diversity phylogenetic relationships of Australasian crocodyliforms based first-hand knowledge relevant fossil material review published literature. The currently known Crocodyliformes spans more than 113 million years, from Early Cretaceous to Holocene, largely consists body fossils discovered continental Australia. Whilst only two crocodyliform genera are recognized Australasia's Mesozoic, Cenozoic is distinguished by remarkable crocodylian crocodyliforms. By far most common crocodylians members Mekosuchinae, whose unambiguously early Eocene until Holocene. addition mekosuchines, during was also inhabited gavialoids species Crocodylus, with four extant latter being surviving Australia New Guinea. crocodylians, particularly have been topic interest palaeontologists for over decades. We performed several analyses test Mekosuchinae other extinct crocodylians. Most results our found as basal crocodyloid clade within Longirostres. However, some recovered an alternative position majority mekosuchines outside Longirostres Late Cretaceous–early Paleogene Orientalosuchina its deeply nested subclade. These suggest had origins Asia Cretaceous, arrived southeast into no later Paleocene. If hypothesis correct, then would longer be endemic since seem persisted Eocene.Jorgo Ristevski [[email protected]], School Biological Sciences, University Queensland, Brisbane, 4072, Australia; Paul M. A. Willis [[email protected]], Flinders University, Adelaide, 2100, South Australia, Adam Yates [[email protected]], Museum Central Art Gallery Northern Territory, Alice Springs, 0870, Matt White [[email protected]], Palaeoscience Research Centre, England, Armidale, 2351, Wales, Australian Age Dinosaurs Natural History, Jump-Up, Winton, 4735, Lachlan J. Hart [[email protected]], Earth Sustainability Science Biological, Environmental Sciences (BEES), Kensington, 2052, Institute, 1 William Street, Sydney, 2010, Michael D. Stein [[email protected]], Center, Gilbert Price [[email protected]], Steven W. Salisbury [[email protected]],

Язык: Английский

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Endocranial anatomy and phylogenetic position of the crocodylian Eosuchus lerichei from the late Paleocene of northwestern Europe and potential adaptations for transoceanic dispersal in gavialoids

The Anatomical Record, Год журнала: 2024, Номер 308(2), С. 636 - 670

Опубликована: Сен. 3, 2024

Abstract Eosuchus lerichei is a gavialoid crocodylian from late Paleocene marine deposits of northwestern Europe, known skull and lower jaws, as well postcrania. Its sister taxon relationship with the approximately contemporaneous species minor east coast USA has been explained through transoceanic dispersal, indicating capability for salt excretion that absent in extant gavialoids. However, there currently no anatomical evidence to support adaptation extinct Furthermore, placement within Gavialoidea labile, some analyses supporting affinities Late Cretaceous early Paleogene “thoracosaurs.” Here we present novel data on internal external anatomy E. enables revised diagnosis, 6 autapormorphies identified genus 10 features enable differentiation . Our phylogenetic recover an diverging gavialid not part “thoracosaur” group. In addition thickened semi‐circular canal walls endosseous labyrinth paratympanic sinus reduction, identify potential osteological correlates glands surface prefrontal lacrimal bones These potentially provide dispersal , also them Portugalosuchus Given earliest stratigraphically oldest gavialoids either have nasal gland and/or recovered deposits, this suggests capacity might be ancestral Gavialoidea. Mapping geological onto phylogeny indicates was probably more than one independent loss/reduction

Язык: Английский

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The neuroanatomy and pneumaticity of Hamadasuchus (Crocodylomorpha, Peirosauridae) from the Cretaceous of Morocco and its paleoecological significance for altirostral forms

Journal of Anatomy, Год журнала: 2023, Номер 243(3), С. 374 - 393

Опубликована: Июнь 13, 2023

We describe the endocranial structures of Hamadasuchus, a peirosaurid crocodylomorph from late Albian-Cenomanian Kem group Morocco. The cranial endocast, associated nerves and arteries, endosseous labyrinths, pneumatization, as well bones braincase new specimen, are reconstructed compared with extant fossil crocodylomorphs, which represent different lifestyles. Cranial this specimen identified belonging to close affinities Rukwasuchus yajabalijekundu, another 'middle' Cretaceous Tanzania. comparable those R. yajabalijekundu but also baurusuchids sebecids (sebecosuchians). Paleobiological traits such alert head posture, ecology, behavior explored for first time, using quantitative metrics. expanded narrow semi-circular canals enlarged pneumatization skull Hamadasuchus linked terrestrial lifestyle. Continuing work on neuroanatomy supposedly crocodylomorphs needs be broadened other groups will allow characterize whether some internal affected by lifestyle these organisms.

Язык: Английский

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A review of the non‐semiaquatic adaptations of extinct crocodylomorphs throughout their fossil record

The Anatomical Record, Год журнала: 2024, Номер 308(2), С. 266 - 314

Опубликована: Ноя. 25, 2024

Abstract Crocodylomorphs constitute a clade of archosaurs that have thrived since the Mesozoic until today and survived numerous major biological crises. Contrary to historic belief, their semiaquatic extant representatives (crocodylians) are not living fossils, and, during evolutionary history, crocodylomorphs evolved live in variety environments. This review aims summarize non‐semiaquatic adaptations (i.e., either terrestrial or fully aquatic) different groups from periods, highlighting how exactly those lifestyles inferred for animals, with regard geographic temporal distribution phylogenetic relationships. The ancestral condition Crocodylomorpha seems been lifestyle, linked several morphological such as an altirostral skull, long limbs allowing erect posture specialized dentition diets based on land. However, some members this clade, thalattosuchians dyrosaurids display opposite, aquatic interestingly same type observations. Finally, new techniques inferring paleobiology extinct animals put forward last decade, appearing complementary approach traditional descriptions comparisons. Such is case paleoneuroanatomical (CT scan data), histological, geochemical studies.

Язык: Английский

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Neuroanatomy of the crocodylomorph Portugalosuchus azenhae from the late cretaceous of Portugal

Journal of Anatomy, Год журнала: 2023, Номер 242(6), С. 1146 - 1171

Опубликована: Фев. 2, 2023

Abstract We present the first detailed braincase anatomical description and neuroanatomical study of Portugalosuchus azenhae , from Cenomanian (Late Cretaceous) Portugal. This eusuchian crocodylomorph was originally described as a putative Crocodylia one oldest representatives this clade; however, its phylogenetic position remains controversial. Based on new data obtained high resolution Computed Tomography images (by micro‐CT scan), aims to improve original taxon also update scarce knowledge Eusuchia time interval, key period understand origin evolution these clades. The resulting three‐dimensional models CT allowed well‐preserved neurocranium internal cavities. Therefore, it possible reconstruct cavities olfactory region, nasopharyngeal ducts, brain, nerves, carotid arteries, blood vessels, paratympanic sinus system inner ear, which estimate some neurosensorial capabilities. By comparison with other crocodylomorphs, analyses showed that back in Cenomanian, already displayed an olfactive acuity, sight, hearing cognitive skills within range observed basal eusuchians crocodylians, including extant species. In addition, order test disputed position, data, helped correct complete observations, were included most recent morphology‐based phylogenies. differs slightly publication since is now located “thoracosaurid” Gavialoidea, but still crocodylian. Despite all this, better contrast results, additional morphological character coding together DNA should be performed.

Язык: Английский

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Neuroanatomy of the crocodylian Tomistoma dowsoni from the Miocene of North Africa provides insights into the evolutionary history of gavialoids

Journal of Anatomy, Год журнала: 2023, Номер 243(1), С. 1 - 22

Опубликована: Март 16, 2023

Abstract The interrelationships of the extant crocodylians Gavialis gangeticus and Tomistoma schlegelii have been historically disputed. Whereas molecular analyses indicate a sister taxon relationship between these two gavialoid species, morphological datasets typically place as outgroup to all other crocodylians. Recent morphological‐based phylogenetic begun resolve this discrepancy, recovering closest living relative ; however, several stratigraphically early fossil taxa are recovered closer than , resulting in anomalously divergence timings. As such, additional data might be required remaining discrepancies. ‘ ’ dowsoni is an extinct species from Miocene North Africa. Utilising CT scans near‐complete, referred skull, we reconstruct neuroanatomy neurosensory apparatus . Based on qualitative quantitative morphometric comparisons with crocodyliforms, characterised by intermediate morphology gavialoids, more closely resembling This mirrors results recent studies based external anatomy three gavialoids. Several neuroanatomical features appear reflect ecological and/or signals. For example, ‘simple’ their broadly similar that long narrow‐snouted (longirostrine), aquatic crocodyliforms. A dorsoventrally short, anteroposteriorly endosseous labyrinth also associated longirostry. These snout skull morphology, which themselves partly constrained ecology, exert influence has recognised birds turtles. Conversely, presence pterygoid bulla its absence could interpreted signal related Gaviali s Evaluation gavialoids will needed further test whether primarily or signal. By incorporating such previously inaccessible information into macroecological studies, can potentially constrain clade's interrelationships, well evaluate timing association evolution features. Finally, our study supports being phylogenetically indicating necessity taxonomic revision species.

Язык: Английский

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Fishboneviz: Enhancing the availability of zooarchaeological fish reference collections through an open access 3D database

Australian Archaeology, Год журнала: 2024, Номер 90(2), С. 236 - 248

Опубликована: Май 3, 2024

Fish remains are a common component of coastal and inland archaeological assemblages from Australia the Pacific Islands. Physical reference collections primary tool that researchers use to taxonomically identify fish bones but given high biodiversity fishes in this region, frequently not complete at genus- species-level. Adjunct resources, such as online photograph repositories bone illustrated technical guides, provide useful supplementary aids. However, 2D photographs illustrations offer fixed perspectives do allow for ready manipulation detailed examination specimen. Here, we introduce Fishboneviz, first open access 3D collection, which was developed reduce inequitable physical line with FAIR principles data management (findable, accessible, interoperable, reusable). A 'best-practice' methodology established facilitate fast effective segmentation (i.e. isolate regions interest elements) Computed Tomography (CT) scans. This way, elements were segmented digital viewing element. To examine effectiveness approach, image procedures applied representative sample 10 per fish: dentary, premaxilla, maxilla, articular, quadrate, hyomandibular, opercle, preopercle, last precaudal vertebra, caudal vertebra. For species within family Labridae, three pharyngeal grinding plates also segmented. These selected they represent different skeleton, variable morphologies, commonly recovered sites. date, collection contains skeletal 26 (18 families). In future, it is hoped will be further expanded by broader network interested collaborators ensure grows according changing needs research teaching communities.

Язык: Английский

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On the Fila Olfactoria and the Cribriform Region of the Crocodylia

Journal of Morphology, Год журнала: 2025, Номер 286(2)

Опубликована: Фев. 1, 2025

ABSTRACT In mammals the fila olfactoria, fascicles of axons coursing from sensory neurons in olfactory epithelium to glomeruli bulb, not only have a topographic projection pattern but also serve as routes for cerebrospinal fluid (CSF) drainage around brain. Les is known about olfactoria nonmammalian taxa. This work explores American alligator ( Alligator mississippiensis ) using combination gross dissection, histology, Diffusible Iodine‐based contrast‐enhanced computed tomography, latex corrosion casting, and India ink tracers. Crocodylians, other vertebrates, courses through foramen nasal capsule rather than an ethmoidal cribriform plate. this filled by dense connective tissue; prominent perineural spaces extend tissue, effectively making it perforate like Latex or introduced into cranial CSF pass reach submucosa epithelium, suggesting that Crocodylians same mammals. , asymmetric, with more entering ventral lateral surfaces bulb dorsal medial surfaces. If individual are traced clear emerges; polarity maintained between rostral‐caudal projecting dorsal‐ventral on bulb.

Язык: Английский

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Cranial anatomy of the mekosuchine crocodylianTrilophosuchus rackhamiWillis, 1993

The Anatomical Record, Год журнала: 2022, Номер 306(2), С. 239 - 297

Опубликована: Авг. 13, 2022

One of the best-preserved crocodylian fossil specimens from Cenozoic Australia is holotype mekosuchine Trilophosuchus rackhami, middle Miocene (13.56 ± 0.67 Ma) Ringtail Site at Riversleigh, northwestern Queensland. Although lacking most snout, skull T. rackhami (QMF16856) has an exceptionally well-preserved cranium. Micro-CT scanning allowed for all preserved cranial bones to be digitally disarticulated, facilitating unprecedented insight into anatomy not just but any mekosuchine. was a small-bodied and one morphologically distinct mekosuchines, characterized by unique combination characteristics several which are exclusive species. Fossil material that definitively referrable species currently known solely Site. However, isolated parietal Hiatus Riversleigh demonstrates also occurred during late Oligocene (~25 Ma), extending range genus more than 10 million years. The new description reevaluation its phylogenetic relationships. Our results reaffirm placement as member Mekosuchinae within subclade Mekosuchini. In analyses, consistently found monophyletic part larger clade Longirostres. assignment subset Crocodylidae brought question, suggesting status subfamily should reconsidered.

Язык: Английский

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Neuroanatomy of the mekosuchine crocodylianTrilophosuchus rackhamiWillis, 1993

Journal of Anatomy, Год журнала: 2022, Номер 241(4), С. 981 - 1013

Опубликована: Авг. 29, 2022

Abstract Although our knowledge on crocodylomorph palaeoneurology has experienced considerable growth in recent years, the neuroanatomy of many taxa yet to be studied. This is true for Australian taxa, where thus far only two crocodylian crocodylomorphs have had aspects their explored. Here, mekosuchine Trilophosuchus rackhami described first time, which significantly increases understanding crocodylians. The palaeoneurological description based taxon's holotype specimen (QMF16856), was subjected a μCT scan. Because exceptional preservation QMF16856, most neuroanatomical elements could digitally reconstructed and detail. Therefore, assessment presented here hitherto in‐depth study this kind an extinct crocodylomorph. brain endocast with distinctive morphology that characterized by acute dural peak over hindbrain region. While overall unique T. , it does share certain similarities notosuchian crocodyliforms Araripesuchus wegeneri Sebecus icaeorhinus . endosseous labyrinth displays typical crocodylians, although stand‐out feature unusually tall common crus. Indeed, crus one greatest height ratios among currently known labyrinths. paratympanic pneumatic system greatly developed similar those extant crocodylians Osteolaemus tetraspis Paleosuchus palpebrosus observations are also discussed context Crocodylomorpha. comparative reinforces previous evaluations complex diverse species, peculiar neuromorphology, particularly eusuchian crocodyliforms.

Язык: Английский

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