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Tomańska A, Stawinoga M, Szturo K, Styczyńska M, Klećkowska-Nawrot J, Janeczek M, Goździewska-Harłajczuk K, Melnyk O, Gębarowski T. Biological Significance of the Komodo Dragon's Tail ( Varanus komodoensis, Varanidae). Animals (Basel) 2024; 14:2142. [PMID: 39123668 PMCID: PMC11311070 DOI: 10.3390/ani14152142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 07/14/2024] [Accepted: 07/16/2024] [Indexed: 08/12/2024] Open
Abstract
The Komodo dragon is a unique reptile with an elongated tail that exhibits hitherto unknown adaptations and functions. This tail, composed of 60-86 vertebrae, serves diverse ecological and physiological roles. In juveniles, it is essential for an arboreal lifestyle and balance, while in adults, it functions as a tool for defense and offensive actions. It possesses characteristic haemal arches and a dorsal keel, along with well-developed muscles which enable precise tail control, influencing the Komodo dragon's maneuverability and directional changes. The tail stores adipose tissue, providing Komodo dragons with the ability to regulate body temperature and independence from other seasonal variations. The tail adipose tissue impacts numerous biochemical processes and may play a crucial role in the animals' metabolic strategies and reproductive capabilities. Its functions include providing essential mineral compounds for the organism, such as calcium, phosphorus, magnesium, iron, and zinc. Analysing the biochemical composition of tail fat is crucial for understanding the health of Komodo dragons.
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Affiliation(s)
- Anna Tomańska
- Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
| | - Martyna Stawinoga
- Veterinary Biotechnology Student Science Club “Refectio”, Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
| | - Kacper Szturo
- Veterinary Biotechnology Student Science Club “Refectio”, Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
| | - Marzena Styczyńska
- Department of Human Nutrition, Faculty of Biotechnology and Food Science, Wroclaw University of Environmental and Life Sciences, Chełmońskiego St. 37/41, 51-630 Wroclaw, Poland
| | - Joanna Klećkowska-Nawrot
- Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
| | - Maciej Janeczek
- Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
| | - Karolina Goździewska-Harłajczuk
- Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
| | - Oleksii Melnyk
- Department of Animal Anatomy, Histology and Pathomorphology, Faculty of Veterinary Medicine, National University of Life and Environmental Sciences of Ukraine, 03041 Kyiv, Ukraine
| | - Tomasz Gębarowski
- Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska St. 1, 51-631 Wrocław, Poland
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Datta D, Bajpai S. Largest known madtsoiid snake from warm Eocene period of India suggests intercontinental Gondwana dispersal. Sci Rep 2024; 14:8054. [PMID: 38637509 DOI: 10.1038/s41598-024-58377-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 03/28/2024] [Indexed: 04/20/2024] Open
Abstract
Here we report the discovery of fossils representing partial vertebral column of a giant madtsoiid snake from an early Middle Eocene (Lutetian, ~ 47 Ma) lignite-bearing succession in Kutch, western India. The estimated body length of ~ 11-15 m makes this new taxon (Vasuki indicus gen et sp. nov.) the largest known madtsoiid snake, which thrived during a warm geological interval with average temperatures estimated at ~ 28 °C. Phylogenetically, Vasuki forms a distinct clade with the Indian Late Cretaceous taxon Madtsoia pisdurensis and the North African Late Eocene Gigantophis garstini. Biogeographic considerations, seen in conjunction with its inter-relationship with other Indian and North African madtsoiids, suggest that Vasuki represents a relic lineage that originated in India. Subsequent India-Asia collision at ~ 50 Ma led to intercontinental dispersal of this lineage from the subcontinent into North Africa through southern Eurasia.
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Affiliation(s)
- Debajit Datta
- Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India.
| | - Sunil Bajpai
- Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India.
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3
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Takesh M, Rastegar-Pouyani N, Gharzi A, Azadbakht M, Jalili C, Anderson SC. A Monograph on the Osteology of Mesopotamian Spiny-tailed Lizards, Saara loricata (Blanford, 1874) (Sauria: Agamidae: Uromastycinae). HERPETOLOGICAL MONOGRAPHS 2020. [DOI: 10.1655/0733-1347-31.4.208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Mohsen Takesh
- Department of Biology, Faculty of Science, Razi University, 6714967346, Kermanshah, Iran
| | | | - Ahmad Gharzi
- Department of Biology, Faculty of Science, Razi University, 6714967346, Kermanshah, Iran
| | - Mehri Azadbakht
- Department of Biology, Faculty of Science, Razi University, 6714967346, Kermanshah, Iran
| | - Cyrus Jalili
- Department of Anatomy and Cell Biology, Kermanshah University of medical Sciences, 6714869914, Kermanshah, Iran
| | - Steven C. Anderson
- University of the Pacific, Department of Biological Sciences, Stockton, California 95211, USA
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Griffin CT, Stocker MR, Colleary C, Stefanic CM, Lessner EJ, Riegler M, Formoso K, Koeller K, Nesbitt SJ. Assessing ontogenetic maturity in extinct saurian reptiles. Biol Rev Camb Philos Soc 2020; 96:470-525. [PMID: 33289322 DOI: 10.1111/brv.12666] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/09/2020] [Accepted: 10/28/2020] [Indexed: 01/06/2023]
Abstract
Morphology forms the most fundamental level of data in vertebrate palaeontology because it is through interpretations of morphology that taxa are identified, creating the basis for broad evolutionary and palaeobiological hypotheses. Assessing maturity is one of the most basic aspects of morphological interpretation and provides the means to study the evolution of ontogenetic changes, population structure and palaeoecology, life-history strategies, and heterochrony along evolutionary lineages that would otherwise be lost to time. Saurian reptiles (the least-inclusive clade containing Lepidosauria and Archosauria) have remained an incredibly diverse, numerous, and disparate clade through their ~260-million-year history. Because of the great disparity in this group, assessing maturity of saurian reptiles is difficult, fraught with methodological and terminological ambiguity. We compiled a novel database of literature, assembling >900 individual instances of saurian maturity assessment, to examine critically how saurian maturity has been diagnosed. We review the often inexact and inconsistent terminology used in saurian maturity assessment (e.g. 'juvenile', 'mature') and provide routes for better clarity and cross-study coherence. We describe the various methods that have been used to assess maturity in every major saurian group, integrating data from both extant and extinct taxa to give a full account of the current state of the field and providing method-specific pitfalls, best practices, and fruitful directions for future research. We recommend that a new standard subsection, 'Ontogenetic Assessment', be added to the Systematic Palaeontology portions of descriptive studies to provide explicit ontogenetic diagnoses with clear criteria. Because the utility of different ontogenetic criteria is highly subclade dependent among saurians, even for widely used methods (e.g. neurocentral suture fusion), we recommend that phylogenetic context, preferably in the form of a phylogenetic bracket, be used to justify the use of a maturity assessment method. Different methods should be used in conjunction as independent lines of evidence when assessing maturity, instead of an ontogenetic diagnosis resting entirely on a single criterion, which is common in the literature. Critically, there is a need for data from extant taxa with well-represented growth series to be integrated with the fossil record to ground maturity assessments of extinct taxa in well-constrained, empirically tested methods.
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Affiliation(s)
- Christopher T Griffin
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
| | - Michelle R Stocker
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
| | - Caitlin Colleary
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Vertebrate Paleontology, Cleveland Museum of Natural History, 1 Wade Oval Drive, Cleveland, OH, 44106, U.S.A
| | - Candice M Stefanic
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Anatomical Sciences, Stony Brook University, 100 Nicolls Road, Stony Brook, NY, 11794, U.S.A
| | - Emily J Lessner
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Pathology and Anatomical Sciences, University of Missouri, 1 Hospital Drive, Columbia, MO, 65212, U.S.A
| | - Mitchell Riegler
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Geological Sciences, University of Florida, 241 Williamson Hall, Gainesville, FL, 32611, U.S.A
| | - Kiersten Formoso
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Earth Sciences, University of Southern California, 3651 Trousdale Pkwy, Los Angeles, CA, 90089, U.S.A
- Dinosaur Institute, Natural History Museum of Los Angeles County, 900 W Exposition Boulevard, Los Angeles, CA, 90007, U.S.A
| | - Krista Koeller
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Biology, University of Florida, 220 Bartram Hall, Gainesville, FL, 32611, U.S.A
| | - Sterling J Nesbitt
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
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Quipildor AM, Quinteros AS, Lobo FJ. Neuroanatomy of the lumbosacral plexus in a highly diversified clade of South-American lizards. Evolution and phylogenetic implications. J Morphol 2020; 281:970-985. [PMID: 32598554 DOI: 10.1002/jmor.21226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/18/2020] [Accepted: 06/04/2020] [Indexed: 11/11/2022]
Abstract
Only few published studies that describe the neuroanatomy of lizards. Here, we describe the neuroanatomy of several Iguanian species belonging to three families (species of Liolaemus and Phymaturus belonging to Liolaemidae, Tropidurus and Stenocercus as representatives of Tropiduridae, and Diplolaemus as a representative of Leiosauridae). Based on Sudan Black B staining and conventional dissections, the neuroanatomy of the lumbosacral region is described. Among the most outstanding results is the existence of a neuronal pattern of the lumbosacral plexus characteristic of Liolaemidae. In addition, it was found that in the genus Liolaemus the lumbosacral plexus is composed of five pairs of spinal nerves while in Phymaturus, Tropidurus, Stenocercus and Diplolaemus is composed from five to six pairs of spinal nerves (from pre-sacral, sacral, and caudal vertebrae). We find differences in the origin of the spinal nerves that constitute the plexus. In some cases, the pattern of nerves involved includes even the caudal vertebrae. Variation among taxa related to the zeugopodial innervation is described, and the homology of these nervous branches is discussed. Sexual differences were found in some species studied. Based on our results and available literature, we found three different patterns of innervation of the zeugopodium. The major contribution of this study is to provide a detailed description of lumbosacral plexus nerves pathways from their origins at the vertebral column to the muscles that they innervate.
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Affiliation(s)
- Angel Matías Quipildor
- IBIGEO (Instituto de Bio y Geociencias del NOA), CONICET-Universidad Nacional de Salta, Salta, Argentina
| | - Andrés Sebastián Quinteros
- IBIGEO (Instituto de Bio y Geociencias del NOA), CONICET-Universidad Nacional de Salta, Salta, Argentina.,Cátedra de Sistemática Filogenética. Facultad de Ciencias Naturales, Universidad Nacional de Salta, Salta, Argentina
| | - Fernando José Lobo
- IBIGEO (Instituto de Bio y Geociencias del NOA), CONICET-Universidad Nacional de Salta, Salta, Argentina.,Cátedra de Anatomía Comparada. Facultad de Ciencias Naturales, Universidad Nacional de Salta, Salta, Argentina
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Čerňanský A, Syromyatnikova EV. The first Miocene fossils of Lacerta cf. trilineata (Squamata, Lacertidae) with a comparative study of the main cranial osteological differences in green lizards and their relatives. PLoS One 2019; 14:e0216191. [PMID: 31433807 PMCID: PMC6703700 DOI: 10.1371/journal.pone.0216191] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/20/2019] [Indexed: 11/28/2022] Open
Abstract
We here describe the first fossil remains of a green lizard of the Lacerta group from the late Miocene (MN 13) of the Solnechnodolsk locality in southern European Russia. This region of Europe is crucial for our understanding of the paleobiogeography and evolution of these middle-sized lizards. Although this clade has a broad geographical distribution across the continent today, its presence in the fossil record has only rarely been reported. In contrast to that, the material described here is abundant, consists of a premaxilla, maxillae, frontals, parietals, jugals, quadrate, pterygoids, dentaries and vertebrae. The comparison of these elements to all extant green lizard species shows that these fossils are indistinguishable from Lacerta trilineata. Thus, they form the first potential evidence of the occurrence of this species in the Miocene. This may be also used as a potential calibration point for further studies. Together with other lizard fossils, Solnechnodolsk shows an interesting combination of survivors and the dawn of modern species. This locality provides important evidence for the transition of an archaic Miocene world to the modern diversity of lizards in Europe. In addition, this article represents a contribution to the knowledge of the comparative osteological anatomy of the selected cranial elements in lacertids. This study gives special emphasis to the green lizards, but new data are also presented for related taxa, e.g., Timon lepidus, Podarcis muralis or Zootoca vivipara. Although the green lizards include several cryptic species for which determination based on isolated osteological material would be expected to be difficult, our comparisons show several important morphological differences, although a high degree of variability is present.
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Affiliation(s)
- Andrej Čerňanský
- Department of Ecology, Laboratory of Evolutionary Biology, Faculty of Natural Sciences, Comenius University in Bratislava, Bratislava, Slovakia
| | - Elena V Syromyatnikova
- Borissiak Paleontological Institute, Russian Academy of Sciences, Moscow, Russia.,Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia
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7
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Camaiti M, Villa A, Wencker LCM, Bauer AM, Stanley EL, Delfino M. Descriptive osteology and patterns of limb loss of the European limbless skink Ophiomorus punctatissimus (Squamata, Scincidae). J Anat 2019; 235:313-345. [PMID: 31125128 DOI: 10.1111/joa.13017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2019] [Indexed: 11/26/2022] Open
Abstract
The limbless skink Ophiomorus punctatissimus is a cryptozoic species found in the Peloponnese region of Greece and on the Greek island Kythira. To provide the first thorough description of the cranial and postcranial osteology of this species, both disarticulated specimens and X-ray computed tomographies of wet-preserved specimens were examined in detail. Resulting from this, an anatomical atlas of this species is provided. Two separate considerations, an evolutionary and an ecomorphological one, are made based on the observed adaptations related to limb loss in this skink. The structure of the girdles shows a particular pattern of reduction: whereas the pelvic girdle is mostly vestigial, the pectoral girdle is instead well developed, with all the elements typical of limbed lizards except for the actual limbs. This led us to hypothesize an asynchronous pattern of limb reduction during the evolution of this species, in which the hindlimbs regressed earlier than the forelimbs. Furthermore, considerations based on overall body morphology, osteology and the structure of the inner ear led to the recognition of this species as a burrowing ecomorph. In contrast to the morphology normally displayed in this ecomorph, O. punctatissimus is characterized by the retention of autotomic vertebrae in its tail. This is consistent with the habitats in which it lives, where active burrowing would be difficult because of the hard, rocky terrain. Instead, this skink hides among rocks on the surface and is, therefore, subject to greater predation risk.
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Affiliation(s)
- Marco Camaiti
- Dipartimento di Scienze della Terra, Università di Torino, Turin, Italy.,School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Andrea Villa
- Dipartimento di Scienze della Terra, Università di Torino, Turin, Italy.,Bayerische Staatssammlung für Paläontologie und Geologie, München, Germany
| | | | - Aaron M Bauer
- Department of Biology, Villanova University, Villanova, PA, USA
| | - Edward L Stanley
- Department of Herpetology, Florida Museum of Natural History, Gainesville, FL, USA
| | - Massimo Delfino
- Dipartimento di Scienze della Terra, Università di Torino, Turin, Italy.,Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Barcelona, Spain
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8
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Tschopp E, Villa A, Camaiti M, Ferro L, Tuveri C, Rook L, Arca M, Delfino M. The first fossils of Timon (Squamata: Lacertinae) from Sardinia (Italy) and potential causes for its local extinction in the Pleistocene. Zool J Linn Soc 2018. [DOI: 10.1093/zoolinnean/zly003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Emanuel Tschopp
- Dipartimento di Scienze della Terra, Università di Torino, Torino, Italy
- Division of Paleontology, American Museum of Natural History, New York City, NY, USA
- Museu da Lourinhã, Lourinhã, Portugal
| | - Andrea Villa
- Dipartimento di Scienze della Terra, Università di Torino, Torino, Italy
| | - Marco Camaiti
- Dipartimento di Scienze della Terra, Università di Torino, Torino, Italy
| | - Letizia Ferro
- Dipartimento di Scienze della Terra, Università di Torino, Torino, Italy
| | - Caterinella Tuveri
- Soprintendenza Archeologia, Belle Arti e Paesaggio per le prov. di Sassari e Nuoro, Nuoro, Italy
| | - Lorenzo Rook
- Dipartimento di Scienze della Terra, Università di Firenze, Firenze, Italy
| | - Marisa Arca
- Soprintendenza Archeologia, Belle Arti e Paesaggio per le prov. di Sassari e Nuoro, Nuoro, Italy
| | - Massimo Delfino
- Dipartimento di Scienze della Terra, Università di Torino, Torino, Italy
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICTA-ICP, Cerdanyola del Vallès, Barcelona, Spain
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Gomes de Souza L. Comments on the Serial Homology and Homologues of Vertebral Lateral Projections in Crocodylia (Eusuchia). Anat Rec (Hoboken) 2018. [PMID: 29516683 DOI: 10.1002/ar.23802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The literature on crocodylian anatomy presents the transverse process in an ambiguous meaning, which could represent all lateral expansions derived from the neural arch, including vertebrae from cervical to caudal series, or in a more restrictive meaning, being applied only to lumbar vertebrae. The lateral expansion of sacral and caudal vertebrae usually referred to as the transverse process has been discovered to be fused ribs, bringing more ambiguity to this term. Therefore, with the lack of a definition for transverse process and other associated terms, the present work aims to propose a nomenclatural standardization, as well as definitions and biological meaning, for vertebral rib related structures. Vertebra obtained from museum collections from a total of 87 specimens of 22 species of all extant Crocodylia genera were studied. All vertebrae, except cervical and first three dorsal, exhibit transverse processes. The transverse process is more developed in dorsal and lumbar vertebrae than in sacral and caudal vertebrae in which it is suppressed by the fused ribs. The serial homology hypotheses here proposed can also be aplied to other Crurotarsi and saurischian dinosaurs specimens. This standardization clarifies the understand of the serial homology among those homotypes, and reduces the ambiguity and misleadings in future work comparisons. Anat Rec, 301:1203-1215, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Lucy Gomes de Souza
- Laboratório de Sistemática e Tafonomia de Vertebrados Fósseis, Setor de Paleovertebrados, Departamento de Geologia e Paleontologia, Museu Nacional/Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, s/no, São Cristóvão, RJ 20940-040, Brazil Rio de Janeiro
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Herne MC, Tait AM, Weisbecker V, Hall M, Nair JP, Cleeland M, Salisbury SW. A new small-bodied ornithopod (Dinosauria, Ornithischia) from a deep, high-energy Early Cretaceous river of the Australian-Antarctic rift system. PeerJ 2018; 5:e4113. [PMID: 29340228 PMCID: PMC5767335 DOI: 10.7717/peerj.4113] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/09/2017] [Indexed: 11/20/2022] Open
Abstract
A new small-bodied ornithopod dinosaur, Diluvicursor pickeringi, gen. et sp. nov., is named from the lower Albian of the Eumeralla Formation in southeastern Australia and helps shed new light on the anatomy and diversity of Gondwanan ornithopods. Comprising an almost complete tail and partial lower right hindlimb, the holotype (NMV P221080) was deposited as a carcass or body-part in a log-filled scour near the base of a deep, high-energy river that incised a faunally rich, substantially forested riverine floodplain within the Australian-Antarctic rift graben. The deposit is termed the 'Eric the Red West Sandstone.' The holotype, interpreted as an older juvenile ∼1.2 m in total length, appears to have endured antemortem trauma to the pes. A referred, isolated posterior caudal vertebra (NMV P229456) from the holotype locality, suggests D. pickeringi grew to at least 2.3 m in length. D. pickeringi is characterised by 10 potential autapomorphies, among which dorsoventrally low neural arches and transversely broad caudal ribs on the anterior-most caudal vertebrae are a visually defining combination of features. These features suggest D. pickeringi had robust anterior caudal musculature and strong locomotor abilities. Another isolated anterior caudal vertebra (NMV P228342) from the same deposit, suggests that the fossil assemblage hosts at least two ornithopod taxa. D. pickeringi and two stratigraphically younger, indeterminate Eumeralla Formation ornithopods from Dinosaur Cove, NMV P185992/P185993 and NMV P186047, are closely related. However, the tail of D. pickeringi is far shorter than that of NMV P185992/P185993 and its pes more robust than that of NMV P186047. Preliminary cladistic analysis, utilising three existing datasets, failed to resolve D. pickeringi beyond a large polytomy of Ornithopoda. However, qualitative assessment of shared anatomical features suggest that the Eumeralla Formation ornithopods, South American Anabisetia saldiviai and Gasparinisaura cincosaltensis, Afro-Laurasian dryosaurids and possibly Antarctic Morrosaurus antarcticus share a close phylogenetic progenitor. Future phylogenetic analysis with improved data on Australian ornithopods will help to test these suggested affinities.
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Affiliation(s)
- Matthew C. Herne
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Alan M. Tait
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, VIC, Australia
| | - Vera Weisbecker
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Michael Hall
- School of Earth, Atmosphere and Environment, Monash University, Melbourne, VIC, Australia
| | - Jay P. Nair
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | | | - Steven W. Salisbury
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
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