DOCSLIB.ORG

Rettili Marini Mesozoici

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Rettili Marini Mesozoici 01/06/2011 Rettili Marini Mesozoici Se la pressione selettiva è favorevole, i Rettili ritornano all’acqua. BASSO tasso metabolico Adattamento TOLLERANZA all’anossia favorito da CAPACITA’ di sfruttare il METABOLISMO ANAEROBICO I gruppi di Rettili marini Mesozoici più importanti sono due: Ichthyosauria Sauropterygia Placodontia “Nothosauria” Plesiosauria 1 01/06/2011 ANAPSIDE SINAPSIDE DIAPSIDE “Parapside” EURYAPSIDE ICHTHYOSAURIA Dal Triassico Inferiore al Cretacico Medio-Superiore Derivazione diapside? Cranio simile a quello euryapside, evolutosi indipendentemente ? Finestra temporale superiore Ittiosauro primitivo? Diapside primitivo? Difficile stabilire l’entità delle convergenze Nanchangosaurus (Hupehsucus) Triassico, Cina 2 01/06/2011 Utatsusaurus Triassico inferiore, Giappone Archi neurali ancora connessi con i centri no processi trasversi “mano simile a pinna ma struttura da tetrapode terrestre. Grippia Triassico inferiore, Spitzbergen Contatto prefrontale-postfrontale Dentatura eterodonte Chaohusaurus Triassico inferiore, Cina Denti su due file http://www.ucmp.berkeley.edu/people/motani/ichthyo/ Ichthyosauria Ittiosauri post -Triassico Ittiosauri triassici 3 01/06/2011 Robusto anello sclerotico Pinna caudale e dorsale senza supp. scheletrico Natatoia, iperdattilia e iperfalangia Centri vertebrali discoidali anficeli •Accorciamento porzioni prossimali dell’arto •Perdita di identità elementi carpo metacarpo •Iperfalangia ed iperdattilia •Perdita mobilità articolare fra le diverse sezioni dell’arto 4 01/06/2011 5 01/06/2011 6 01/06/2011 Cymbospondylus 7 01/06/2011 SAUROPTERYGIA: Nothosauria (Triassico) Nothosauroidea Pachypleurosauroidea La scapola si infila ventralmente alla clavicola Il cinto forma un anello ventrale Pachypleurosauroidea Nothosauroidea 8 01/06/2011 Ceresiosaurus 2m circa I Nothosauroidea presentano un trend evolutivo che va verso un progressivo irrigidimento del tronco ed un passaggio del nuoto da assiale ondulatorio verso un nuoto parassiale simmetrico che si riscontrerà nei Plesiosauria. Numerosi caratteri anatomici ne farebbero gli antenati diretti dei Plesiosauria, ma un carattere morfologico, costituisce un ostacolo. I Nothosauria presentano nel palato un carattere derivato assente nei Plesiosauria: le finestre interpterigoidee sono chiuse, mentre nei Plesiosauria rimane la condizione plesiomorfica, ossia le finestre interpterigoidee sono aperte. 9 01/06/2011 Pistosaurus Questo problema è stato risolto con il ritrovamento di Pistosaurus, un Sauropterigio che mostra uno scheletro postcraniale da Nothosauroidea con un cranio da plesiosauro, con finestre interpterigoidee aperte. Pachypleurosauroidea Nothosauroidea Pistosaurus Plesiosauria PLESIOSAURIA (?Triassico Sup. -Cretacico) Notevole adattamento al nuoto Arti anteriori e posteriori simili fra loro Coda non molto lunga Plesiosauri Tronco completamente rigido Cinti “bassi” ma molto espansi ventralmente Dimensioni generalmente superiori ai notosauri 10 01/06/2011 Arti trasformati in natatoie Cinto pettorale robusto ed espanso ventralmente Coda breve non modificata per il nuoto Gastralia che contribuiscono ad irrigidire il tronco ELASMOSAUROIDEA Estremo allungamento del collo, oltre 70 vertebre cervicali 11 01/06/2011 Pliosauroidea 12 01/06/2011 Cranio molto grande con fauci allungate ed armate di robusti denti conici, situati all’estremità anteriori delle mascelle. Lunghezza da due a oltre venti metri. Probabilmente veloci (e voraci) predatori di mare aperto. Neusticosaurus “Notosauro” Plesiosauro Plesiosauro Giurassico Inferiore Giurassico Superiore 13 01/06/2011 Vertebre: •Incremento dimensioni processi trasversi •Avvicinamento e riduzione zigapofisi Pistosaurus Neusticosaurus Cryptocleidus Tartaruga Plesiosauro Otaria Tartaruga Plesiosauro Pinguino 14 01/06/2011 PLACODONTIA Triassico Medio-Superiore Placodontoidea Coda lunga ma Placodontia non compressa Cyamodontoidea lateralmente Arti non modificati per il nuoto Cinto pettorale, vista ventrale Sezione frontale tronco Cinto pelvico vista ventrale •Ampia finestra temporale •Robusta barra sq-j-po (muscolatura mandibolare) •Denti trituranti 15 01/06/2011 Cyamodontoidea Psephoderma, Triassico Superiore Psephoderma Nei ciamodontoidi evoluti si ha scomparsa dei denti premascellari durante l’ontogenesi 16 01/06/2011 Henodus, Triassico Superiore 17.
Load more

Recommended publications
  • (Diapsida: Saurosphargidae), with Implications for the Morphological Diversity and Phylogeny of the Group
    Geol. Mag.: page 1 of 21. c Cambridge University Press 2013 1 doi:10.1017/S001675681300023X A new species of Largocephalosaurus (Diapsida: Saurosphargidae), with implications for the morphological diversity and phylogeny of the group ∗ CHUN LI †, DA-YONG JIANG‡, LONG CHENG§, XIAO-CHUN WU†¶ & OLIVIER RIEPPEL ∗ Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China ‡Department of Geology and Geological Museum, Peking University, Beijing 100871, PR China §Wuhan Institute of Geology and Mineral Resources, Wuhan, 430223, PR China ¶Canadian Museum of Nature, PO Box 3443, STN ‘D’, Ottawa, ON K1P 6P4, Canada Department of Geology, The Field Museum, 1400 S. Lake Shore Drive, Chicago, IL 60605-2496, USA (Received 31 July 2012; accepted 25 February 2013) Abstract – Largocephalosaurus polycarpon Cheng et al. 2012a was erected after the study of the skull and some parts of a skeleton and considered to be an eosauropterygian. Here we describe a new species of the genus, Largocephalosaurus qianensis, based on three specimens. The new species provides many anatomical details which were described only briefly or not at all in the type species, and clearly indicates that Largocephalosaurus is a saurosphargid. It differs from the type species mainly in having three premaxillary teeth, a very short retroarticular process, a large pineal foramen, two sacral vertebrae, and elongated small granular osteoderms mixed with some large ones along the lateral most side of the body. With additional information from the new species, we revise the diagnosis and the phylogenetic relationships of Largocephalosaurus and clarify a set of diagnostic features for the Saurosphargidae Li et al.
    [Show full text]
  • Mesozoic Marine Reptile Palaeobiogeography in Response to Drifting Plates
    ÔØ ÅÒÙ×Ö ÔØ Mesozoic marine reptile palaeobiogeography in response to drifting plates N. Bardet, J. Falconnet, V. Fischer, A. Houssaye, S. Jouve, X. Pereda Suberbiola, A. P´erez-Garc´ıa, J.-C. Rage, P. Vincent PII: S1342-937X(14)00183-X DOI: doi: 10.1016/j.gr.2014.05.005 Reference: GR 1267 To appear in: Gondwana Research Received date: 19 November 2013 Revised date: 6 May 2014 Accepted date: 14 May 2014 Please cite this article as: Bardet, N., Falconnet, J., Fischer, V., Houssaye, A., Jouve, S., Pereda Suberbiola, X., P´erez-Garc´ıa, A., Rage, J.-C., Vincent, P., Mesozoic marine reptile palaeobiogeography in response to drifting plates, Gondwana Research (2014), doi: 10.1016/j.gr.2014.05.005 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT Mesozoic marine reptile palaeobiogeography in response to drifting plates To Alfred Wegener (1880-1930) Bardet N.a*, Falconnet J. a, Fischer V.b, Houssaye A.c, Jouve S.d, Pereda Suberbiola X.e, Pérez-García A.f, Rage J.-C.a and Vincent P.a,g a Sorbonne Universités CR2P, CNRS-MNHN-UPMC, Département Histoire de la Terre, Muséum National d’Histoire Naturelle, CP 38, 57 rue Cuvier,
    [Show full text]
  • Sauropterygia I Placodontia, Pachypleurosauria, Nothosauroidea, Pistosauroidea
    Teil 12A / Part 12A Sauropterygia I Placodontia, Pachypleurosauria, Nothosauroidea, Pistosauroidea by O. RlEPPEL With 80 Figures Verlag Dr. Friedrich Pfeil • Munchen 2000 ISBN 3-931516-78-4 Contents Foreword (P. WELLNHOFER) V Acknowledgements VI Institutional Acronyms VII Figure Abbreviations VIII Introduction: History of the Concept of Sauropterygia 1 Phylogenetic Relationships of Stem-Group Sauropterygia 4 Stratigraphic and Geographic Distribution of Stem-Group Sauropterygia 6 General Skeletal Anatomy of Stem-Group Sauropterygia 10 Systematic Review 16 Superorder Sauropterygia OWEN, 1860 16 Order Placodontia COPE, 1871 16 Suborder Placodontoidea COPE, 1871 16 Family Paraplacodontidae PEYER & KUHN-SCHNYDER, 1955 17 Anatomy of Paraplacodontidae 17 Genus Paraplacodus PEYER, 1931 18 Family Placodontidae COPE, 1871 19 Anatomy of Placodontidae 19 Genus Placodus AGASSIZ, 1933 21 Suborder Cyamodontoidea NOPCSA, 1923 23 Anatomy of Cyamodontoidea 23 Interrelationships of Cyamodontoidea 25 Superfamily Cyamodontida NOPCSA, 1923 25 Family Henodontidae F. v. HUENE, 1948 26 Genus Henodus F. v. HUENE, 1936 26 Family Cyamodontidae NOPCSA, 1923 27 Genus Cyamodus MEYER, 1863 27 Superfamily Placochelyida ROMER, 1956 32 Family Macroplacidae nov. fam 32 Genus Macroplacus SCHUBERT-KLEMPNAUER, 1975 32 Family Protenodontosauridae nov. fam 33 Genus Protenodontosaurus PINNA, 1990 33 Family Placochelyidae ROMER, 1956 34 Genus Placochelys JAEKEL, 1902 34 Genus Psephoderma MEYER, 1858 36 Genus Psephosaurus E. FRAAS, 1896 38 Cyamodontoidea indet 39 IX Order Eosauropterygia
    [Show full text]
  • Exceptional Vertebrate Biotas from the Triassic of China, and the Expansion of Marine Ecosystems After the Permo-Triassic Mass Extinction
    Earth-Science Reviews 125 (2013) 199–243 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Exceptional vertebrate biotas from the Triassic of China, and the expansion of marine ecosystems after the Permo-Triassic mass extinction Michael J. Benton a,⁎, Qiyue Zhang b, Shixue Hu b, Zhong-Qiang Chen c, Wen Wen b, Jun Liu b, Jinyuan Huang b, Changyong Zhou b, Tao Xie b, Jinnan Tong c, Brian Choo d a School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK b Chengdu Center of China Geological Survey, Chengdu 610081, China c State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Wuhan 430074, China d Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China article info abstract Article history: The Triassic was a time of turmoil, as life recovered from the most devastating of all mass extinctions, the Received 11 February 2013 Permo-Triassic event 252 million years ago. The Triassic marine rock succession of southwest China provides Accepted 31 May 2013 unique documentation of the recovery of marine life through a series of well dated, exceptionally preserved Available online 20 June 2013 fossil assemblages in the Daye, Guanling, Zhuganpo, and Xiaowa formations. New work shows the richness of the faunas of fishes and reptiles, and that recovery of vertebrate faunas was delayed by harsh environmental Keywords: conditions and then occurred rapidly in the Anisian. The key faunas of fishes and reptiles come from a limited Triassic Recovery area in eastern Yunnan and western Guizhou provinces, and these may be dated relative to shared strati- Reptile graphic units, and their palaeoenvironments reconstructed.
    [Show full text]
  • Tesis Doctoral 2018
    TESIS DOCTORAL 2018 HISTORIA EVOLUTIVA DE SIMOSAURIDAE (SAUROPTERYGIA). CONTEXTO SISTEMÁTICO Y BIOGEOGRÁFICO DE LOS REPTILES MARINOS DEL TRIÁSICO DE LA PENÍNSULA IBÉRICA CARLOS DE MIGUEL CHAVES PROGRAMA DE DOCTORADO EN CIENCIAS FRANCISCO ORTEGA COLOMA ADÁN PÉREZ GARCÍA RESUMEN Los sauropterigios fueron un exitoso grupo de reptiles marinos que vivió durante el Mesozoico, apareciendo en el Triásico Inferior y desapareciendo a finales del Cretácico Superior. Este grupo alcanzó su máxima disparidad conocida durante el Triásico Medio e inicios del Triásico Superior, diversificándose en numerosos grupos con distintos modos de vida y adaptaciones tróficas. El registro fósil de este grupo durante el Triásico es bien conocido a nivel global, habiéndose hallado abundantes restos en Norteamérica, Europa, el norte de África, Oriente Próximo y China. A pesar del relativamente abundante registro de sauropterigios triásicos ibéricos, los restos encontrados son, por lo general, elementos aislados y poco informativos a nivel sistemático en comparación con los de otros países europeos como Alemania, Francia o Italia. En la presente tesis doctoral se realiza una puesta al día sobre el registro ibérico triásico de Sauropterygia, con especial énfasis en el clado Simosauridae, cuyo registro ibérico permanecía hasta ahora inédito. Además de la revisión de ejemplares de sauropterigios previamente conocidos, se estudian numerosos ejemplares inéditos. De esta manera, se evalúan hipótesis previas sobre la diversidad peninsular de este clado y se reconocen tanto formas definidas en otras regiones europeas y de Oriente Próximo, pero hasta ahora no identificadas en la península ibérica, como nuevos taxones. La definición de nuevas formas y el incremento de la información sobre otras previamente conocidas permiten la propuesta de hipótesis filogenéticas y la redefinición de varios taxones.
    [Show full text]
  • Late Cretaceous) of Morocco : Palaeobiological and Behavioral Implications Remi Allemand
    Endocranial microtomographic study of marine reptiles (Plesiosauria and Mosasauroidea) from the Turonian (Late Cretaceous) of Morocco : palaeobiological and behavioral implications Remi Allemand To cite this version: Remi Allemand. Endocranial microtomographic study of marine reptiles (Plesiosauria and Mosasauroidea) from the Turonian (Late Cretaceous) of Morocco : palaeobiological and behavioral implications. Paleontology. Museum national d’histoire naturelle - MNHN PARIS, 2017. English. NNT : 2017MNHN0015. tel-02375321 HAL Id: tel-02375321 https://tel.archives-ouvertes.fr/tel-02375321 Submitted on 22 Nov 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. MUSEUM NATIONAL D’HISTOIRE NATURELLE Ecole Doctorale Sciences de la Nature et de l’Homme – ED 227 Année 2017 N° attribué par la bibliothèque |_|_|_|_|_|_|_|_|_|_|_|_| THESE Pour obtenir le grade de DOCTEUR DU MUSEUM NATIONAL D’HISTOIRE NATURELLE Spécialité : Paléontologie Présentée et soutenue publiquement par Rémi ALLEMAND Le 21 novembre 2017 Etude microtomographique de l’endocrâne de reptiles marins (Plesiosauria et Mosasauroidea) du Turonien (Crétacé supérieur) du Maroc : implications paléobiologiques et comportementales Sous la direction de : Mme BARDET Nathalie, Directrice de Recherche CNRS et les co-directions de : Mme VINCENT Peggy, Chargée de Recherche CNRS et Mme HOUSSAYE Alexandra, Chargée de Recherche CNRS Composition du jury : M.
    [Show full text]
  • Microstructure of Vertebrae, Ribs, and Gastralia of Triassic
    Microstructure of Vertebrae, Ribs, and Gastralia of Triassic Sauropterygians-New Insights into the Microanatomical Processes Involved in Aquatic Adaptations of Marine Reptiles Nicole Klein, Aurore Canoville, Alexandra Houssaye To cite this version: Nicole Klein, Aurore Canoville, Alexandra Houssaye. Microstructure of Vertebrae, Ribs, and Gas- tralia of Triassic Sauropterygians-New Insights into the Microanatomical Processes Involved in Aquatic Adaptations of Marine Reptiles. Anatomical Record: Advances in Integrative Anatomy and Evolu- tionary Biology, Wiley-Blackwell, 2019, 302 (10), pp.1770-1791. 10.1002/ar.24140. hal-02351319 HAL Id: hal-02351319 https://hal.archives-ouvertes.fr/hal-02351319 Submitted on 7 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Microstructure of vertebrae, ribs, and gastralia of Triassic sauropterygians – New insights into the microanatomical processes involved in aquatic adaptations of marine reptiles Nicole Klein1*, Aurore Canoville2, and Alexandra Houssaye3 1Steinmann Institute, Paleontology, University of Bonn, Nussallee 8, 53115 Bonn, Germany. 2 Department of Biological Sciences, North Carolina State University & Paleontology, North Carolina Museum of Natural Sciences, 11 W. Jones St, Raleigh, NC 27601, USA. 3UMR 7179 CNRS/Muséum National d’Histoire Naturelle, Département Adaptations du Vivant, 57 rue Cuvier CP-55, 75005 Paris, France.
    [Show full text]
  • Sauropterygia, Placodontia) from the Late Triassic of Schesaplana Mountain, Graubu¨Nden, Switzerland
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by RERO DOC Digital Library Swiss J Geosci (2014) 107:349–357 DOI 10.1007/s00015-014-0173-9 New specimen of Psephoderma alpinum (Sauropterygia, Placodontia) from the Late Triassic of Schesaplana Mountain, Graubu¨nden, Switzerland James M. Neenan • Torsten M. Scheyer Received: 22 October 2014 / Accepted: 22 October 2014 / Published online: 20 November 2014 Ó Swiss Geological Society 2014 Abstract Psephoderma alpinum is an armoured, duro- Abbreviations phagous placodont known from the alpine Late Triassic. IVPP Institute of Vertebrate Paleontology and Here we present a new, well-preserved isolated skull dis- Paleoanthropology, China covered in the Alplihorn Member (Late Norian–Early MB.R. Museum fu¨r Naturkunde der Humboldt Rhaetian) of the Ko¨ssen Formation, Schesaplana Mountain, Universita¨t, Berlin, Germany which straddles the Swiss/Austrian border. Micro-com- MSNM Museo Civico di Storia Naturale di Milano, Italy puted tomographic (lCT) scanning was used to create an PIMUZ Palaeontological Institute and Museum, accurate osteological reconstruction of the specimen, the University of Zurich, Switzerland first time this has been conducted for Psephoderma.We thus clarify disputed anatomical features from previous descriptions, such as a lack of a lacrimal and a pineal foramen that is enclosed by the parietal. We also present 1 Introduction the first description based on lCT data of the lateral braincase wall, sphenoid region and some cranial nerve Psephoderma alpinum Meyer 1858 is a highly-nested, canals for Psephoderma, with the location of the hypo- armoured placodont best known from the Norian and physeal seat, cerebral carotid foramina, dorsum sellae, Rhaetian (Late Triassic) of the Alps (e.g., Rieppel 2000, prootic foramen, lacrimal foramen, as well as all dental 2001).
    [Show full text]
  • Revision of the Genus Styxosaurus and Relationships of the Late Cretaceous Elasmosaurids (Sauropterygia: Plesiosauria) of the Western Interior Seaway
    Marshall University Marshall Digital Scholar Theses, Dissertations and Capstones 2020 Revision of the Genus Styxosaurus and Relationships of the Late Cretaceous Elasmosaurids (Sauropterygia: Plesiosauria) of the Western Interior Seaway Elliott Armour Smith Follow this and additional works at: https://mds.marshall.edu/etd Part of the Biology Commons, Paleobiology Commons, and the Paleontology Commons REVISION OF THE GENUS STYXOSAURUS AND RELATIONSHIPS OF THE LATE CRETACEOUS ELASMOSAURIDS (SAUROPTERYGIA: PLESIOSAURIA) OF THE WESTERN INTERIOR SEAWAY A thesis submitted to the Graduate College of Marshall University In partial fulfillment of the requirements for the degree of Master of Science In Biological Sciences by Elliott Armour Smith Approved by Dr. F. Robin O’Keefe, Committee Chairperson Dr. Habiba Chirchir, Committee Member Dr. Herman Mays, Committee Member Marshall University May 2020 ii © 2020 Elliott Armour Smith ALL RIGHTS RESERVED iii DEDICATION Dedicated to my loving parents for supporting me on my journey as a scientist. iv ACKNOWLEDGEMENTS I would like to thank Dr. Robin O’Keefe for serving as my advisor, and for his constant mentorship and invaluable contributions to this manuscript. I would like to thank Dr. Herman Mays and Dr. Habiba Chirchir for serving on my committee and providing immensely valuable feedback on this manuscript and the ideas within. Thanks to the Marshall University Department of Biological Sciences for travel support. I would like to thank curators Ross Secord (University of Nebraska), Chris Beard (University of Kansas), Tylor Lyson (Denver Museum of Nature and Science), and Darrin Paginac (South Dakota School of Mines and Technology) for granting access to fossil specimens. Thanks to Joel Nielsen (University of Nebraska State Museum), Megan Sims (University of Kansas), Kristen MacKenzie (Denver Museum of Nature and Science) for facilitating access to fossil specimens.
    [Show full text]
  • Evolution Et Extinction Des Reptiles Marins Au Cours Du Mesozoique
    EVOLUTION ET EXTINCTION DES REPTILES MARINS AU COURS DU MESOZOIQUE par Nathalie BARDET * SOMMAIRE Page Résumé, Abstract . 178 Introduction ..................................................................... 179 Matériel et méthode . 181 La notion de reptile marin . 181 Etude systématique . 182 Etude stratigraphique. 183 Méthodes d'analyse. 183 Systématique et phylogénie. 184 Le registre fossile des reptiles marins . 184 Affinités et phylogénie des reptiles marins. 186 Analyses taxinomique et stratigraphique. 187 Testudines (Chelonia) . 187 Squamata, Lacertilia . 191 Squamata, Serpentes. 193 Crocodylia ............................................................... 194 Thalattosauria . 195 Hupehsuchia . 196 Helveticosauroidea . 197 Pachypleurosauroidea . 197 Sauropterygia .... 198 Placodontia. 198 * Laboratoire de Paléontologie des Vertébrés, URA 1761 du CNRS, Université Pierre et Marie Curie, Case 106,4 Place Jussieu, 75252 Paris cédex 05, France. Mots-clés: Reptiles marins, Tortues, Lézards, Serpents, Crocodiles, Thalattosaures, Hupehsuchiens, Helveticosaures, Pachypleurosaures, Nothosaures, Placodontes, Plésiosaures, Ichthyosaures, Mésozoïque, Evolution, Extinction, Assemblages et Renouvellements fauniques. Key-words: Marine Reptiles, Turtles, Lizards, Snakes, Crocodiles, Thalattosaurs, Hupehsuchians, Helveticosaurs, Pachypleurosaurs, Nothosaurs, Placodonts, Plesiosaurs, Ichthyosaurs, Mesozoic, Evolution, Extinction, Faunal Assemblages and Turnovers. Palaeovertebrata. Montpellier. 24 (3-4): 177-283, 13 fig. (Reçu le 4 Juillet 1994,
    [Show full text]
  • Long Bone Histology and Microanatomy of Placodontia (Diapsida: Sauropterygia)
    Contributions to Zoology, 84 (1) 59-84 (2015) Long bone histology and microanatomy of Placodontia (Diapsida: Sauropterygia) Nicole Klein1, 5, Alexandra Houssaye2, James M. Neenan3, 4, Torsten M. Scheyer3 1Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191 Stuttgart 2UMR 7179 CNRS/Muséum National d’Histoire Naturelle, Département Ecologie et Gestion de la Biodiversité, 57 rue Cuvier CP-55, 75000 Paris, France 3Paläontologisches Institut und Museum, Universität Zürich, Karl Schmid-Strasse 4, CH-8006 Zurich, Switzerland 4The Function, Evolution and Anatomy Research (FEAR) Lab; School of Environmental and Rural Science; Univer- sity of New England, Armidale NSW 2351, Australia 5 Email: [email protected] Key words: bone mass increase, bone tissue types, extinct marine reptiles, high growth rates, PCA, swimming capa- bilities, Triassic Abstract Henodus, Placodontia indet. aff. Cyamodus, non-armoured Pla- codus, and Placodontia indet. Bone tissue of Psephoderma and Placodontia, an enigmatic group of durophagous and in part Paraplacodus indicates low growth rates and a low basal meta- heavily armoured animals, were members of Sauropterygia, the bolic rate, as many modern sauropsids have such as the marine most diverse and successful group of Mesozoic marine reptiles. iguana, whereas the others grew with extremely fast growth Microanatomy and histology of long bones of several armoured rates, more typical for birds and mammals, indicating an in- and non-armoured Placodontia were studied, covering most of creased basal metabolic rate. their taxonomic breadth, to elucidate the paleoecology, physiol- ogy, and lifestyle of its members. Results reveal an unexpected and not phylogenetically or stratigraphically related disparity of microanatomical and histological features for the group.
    [Show full text]
  • Dentition and Feeding in Placodontia: Tooth Replacement in Henodus Chelyops Yannick Pommery1,2,3, Torsten M
    Pommery et al. BMC Ecol Evo (2021) 21:136 BMC Ecology and Evolution https://doi.org/10.1186/s12862-021-01835-4 RESEARCH Open Access Dentition and feeding in Placodontia: tooth replacement in Henodus chelyops Yannick Pommery1,2,3, Torsten M. Scheyer4 , James M. Neenan5 , Tobias Reich4, Vincent Fernandez6,7 , Dennis F. A. E. Voeten6,8,9 , Adrian S. Losko10 and Ingmar Werneburg1,2* Abstract Background: Placodontia is a Triassic sauropterygian reptile group characterized by fat and enlarged crushing teeth adapted to a durophagous diet. The enigmatic placodont Henodus chelyops has numerous autapomorphic character states, including extreme tooth count reduction to only a single pair of palatine and dentary crushing teeth. This ren- ders the species unusual among placodonts and challenges identifcation of its phylogenetic position. Results: The skulls of two Henodus chelyops specimens were visualized with synchrotron tomography to investigate the complete anatomy of their functional and replacement crushing dentition in 3D. All teeth of both specimens were segmented, measured, and statistically compared to reveal that H. chelyops teeth are much smaller than the posterior palatine teeth of other cyamodontoid placodonts with the exception of Parahenodus atancensis from the Iberian Peninsula. The replacement teeth of this species are quite similar in size and morphology to the functional teeth. Conclusion: As other placodonts, Henodus chelyops exhibits vertical tooth replacement. This suggests that verti- cal tooth replacement arose relatively early in placodont phylogeny. Analysis of dental morphology in H. chelyops revealed a concave shape of the occlusal surface and the notable absence of a central cusp. This dental morphology could have reduced dental wear and protected against failure.
    [Show full text]