DOCSLIB.ORG

A New Elasmosaurid from the Early Maastrichtian of Angola and the Implications of Girdle Morphology on Swimming Style in Plesiosaurs

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A New Elasmosaurid from the Early Maastrichtian of Angola and the Implications of Girdle Morphology on Swimming Style in Plesiosaurs Netherlands Journal of Geosciences —– Geologie en Mijnbouw | 94 – 1 | 109-120 | 2015 doi: 10.1017/njg.2014.44 A new elasmosaurid from the early Maastrichtian of Angola and the implications of girdle morphology on swimming style in plesiosaurs R. Araujo´ 1,2,*,M.J.Polcyn1,A.S.Schulp3,O.Mateus2,4,L.L.Jacobs1,A.Ol´ımpio Gonçalves5 & M.-L. Morais5 1 Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, Texas, 75275, USA 2 Museu da Lourinh~a, Rua Jo~ao Lu´ıs de Moura, 2530-157 Lourinh~a, Portugal 3 Naturalis Biodiversity Center, Darwinweg 2, 2333CR Leiden, the Netherlands and Natuurhistorisch Museum Maastricht, Maastricht, the Netherlands and Faculty of Earth and Life Sciences, Amsterdam VU University, Amsterdam, the Netherlands 4 UniversidadeNovadeLisboa,CICEGe,FaculdadedeCiˆencias e Tecnologia, FCT, 2829-516 Caparica, Portugal 5 Departamento de Geologia, Faculdade de Ciencas, Universidade Agostinho Neto, Avenida 4 de Fevereiro 7, Luanda, Angola * Corresponding author. Email: [email protected] Manuscript received: 2 May 2014, accepted: 3 December 2014 Abstract We report here a new elasmosaurid from the early Maastrichtian at Bentiaba, southern Angola. Phylogenetic analysis places the new taxon as the sister taxon to Styxosaurus snowii, and that clade as the sister of a clade composed of (Hydrotherosaurus alexandrae (Libonectes morgani + Elasmosaurus platyurus)). The new taxon has a reduced dorsal blade of the scapula, a feature unique amongst elasmosaurids, but convergent with cryptoclidid plesiosaurs, and indicatesalongi- tudinal protraction-retraction limb cycle rowing style with simple pitch rotation at the glenohumeral articulation. Morphometric phylogenetic analysis of the coracoids of 40 eosauropterygian taxa suggests that there was a broad range of swimming styles within the clade. Keywords: Plesiosauria, locomotion, pectoral girdle, Elasmosauridae, marine reptiles Introduction from the mid-Hauterivian (Evans, 2012) to the end of the Maas- trichtian (Vincent et al., 2011). We report here a new elasmosaurid plesiosaur from the early By the earliest Jurassic, plesiosaurs were fully adapted to Maastrichtian of Angola, and provide a description and a phylo- a pelagic lifestyle and two major Bauplans (plesiosauromorph genetic analysis. The new taxon possesses unusual features of and pliosauromorph) had emerged in multiple phylogenetic lin- the limb and pectoral girdle morphology that suggest a peculiar eages (O’Keefe, 2001; Benson et al., 2012). Plesiosauromorphs mode of locomotion; we therefore also explore the implications have long necks and relatively small, anteriorly abbreviated of girdle morphology on swimming style in a phylogenetic mor- heads, whereas the pliosauromorph Bauplan includes forms phometrics framework. with larger elongate heads and relatively short necks (O’Keefe Plesiosaurs are members of the Eosauropterygia (Rieppel, & Carrano, 2005). However, all plesiosaurs share unique fea- 1994), which include pachypleurosaurs, nothosaurs and pisto- tures of their limbs and girdles amongst secondarily adapted saursbestknownfromtheMiddleTriassic epicontinental shal- Mesozoic marine reptiles. Swimming style based on paraxial low seas of Europe and China (Rieppel, 2000). Elasmosauridae quadrupedal locomotion is largely accepted (e.g. Watson, are regarded as the sister group of Cryptocleididae within 1924; Robinson, 1975), although details of limb motion Plesiosauria (Ketchum & Benson, 2010; Benson & Druckenmiller, are more contentious (e.g. Thewissen & Taylor, 2007; Lingham- 2014). The origin of Elasmosauridae is unclear but its record extends Soliar, 2000). © Netherlands Journal of Geosciences Foundation 2014 109 Downloaded from https://www.cambridge.org/core. IP address: 170.106.33.42, on 23 Sep 2021 at 19:59:54, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/njg.2014.44 Netherlands Journal of Geosciences —– Geologie en Mijnbouw 94 – 1 | 2015 The morphological transition between terrestrial forms, pre- Phylogeny sumably in the early Triassic, to fully marine forms known from the Jurassic and Cretaceous involves profound reorganisation Phylogenetic analyses of the new taxon used the data matrix of 177 of the girdle elements along with elaboration of the limbs as characters and 67 taxa modified from Ketchum & Benson (2010), with paddles in a unique body plan without modern analogue. Ple- the nothosaurid Cymatosaurus, as the outgroup. Codings can be found siosaurs likely share a distant relationship with terrestrial in the Appendix. The analysis was run in TNT v1.1 (Goloboff et al., sprawlers (Rieppel, 1997, 2000) and on entry to the marine 2008) with 20 independent hits using the defaults of ‘xmult’ command realm employed paraxial rowing (Schmidt, 1984; Storrs, 1986; and 10 cycles of tree drifting (Goloboff et al., 2008). Tree Fuse was run Lin & Rieppel, 1998; for a different opinion see Sues, 1987). with 22 replicates and over 1 3 109 rearrangements. A single parsimo- Within Diapsida, there are two primary modes of aquatic loco- nious tree was retrieved with a tree length of 1136.78. Resampling motion: limb-based swimming (e.g. turtles, penguins) and scores were calculated using 100 replications of symmetric resampling trunk-and-tail-based lateral undulation (e.g. varanoids, igua- (Goloboff et al., 2003). Each data set was analysed with a single addi- nids,crocodyliforms).Amongextantparaxialswimmersthere tion and the resulting tree collapsed with tree bisection reconnection are two main styles: rowing (e.g. trionychid turtles) and under- (TBR) (Goloboff & Farris, 2001). Group supports were calculated by water flying (e.g. sea turtles). In underwater rowing the main TBR-swapping the trees, and registering of the number of steps needed locomotory vector components are protraction and retraction, to unite a clade. Both absolute (Bremer, 1994) and relative Bremer sup- whereas in underwater flying the main locomotory vector com- ports are presented (Goloboff & Farris, 2001). Continuous characters ponent is adduction and abduction (Carpenter et al., 2010). (both meristic and non-meristic) were analysed as such (Goloboff Within plesiosaurs, both rowing and underwater flying have et al., 2006), i.e. ranges and ratios were plotted in the matrix with been proposed (Watson, 1924; Robinson, 1975; Carpenter the actual values, without the need to create arbitrary groupings. ´ et al., 2010). Araujo & Correia (in press) provide a detailed Vincent et al. (2011) matrix was also coded and is 67 characters 3 analysis of the pectoral myology of plesiosaurs. 22 taxa, focused particularly on elasmosaurid taxa (10 out of 23). In this contribution, we first describe the osteology of the The outgroup included the pachypleurosaur Serpianosaurus and the new taxon and perform a character-based parsimony analysis nothosaur Simosaurus. to determine its phylogenetic position. We then perform an additional analysis employing a continuously variable Phylogenetics morphometrics morphometric character, a quantification of coracoid shape, to develop a testable model of evolution for this bone in In order to develop a testable model of morphological evolution Eosauropterygia. We conclude with a brief discussion of the of the coracoid, we also performed a phylogenetic morphomet- implications of girdle and limb morphology and musculature ric analysis following the methods of Catalano et al. (2010) and variationonswimmingstyleinplesiosaurs. Goloboff & Catalano (2011). Phylogenetic morphometrics employs Farris optimisation by applying parsimony analysis to 2D or 3D spatial continuum (Catalano et al., 2010) using homol- Materials and methods ogous landmarks. A set of landmarks is regarded as a single character by the algorithm. In this case, one character with Institutional abbreviations 14 landmarks was used, forming the character ‘outline shape of the right coracoid in ventral view’. Forty pachypleurosaur, CMN – Canadian Museum of Nature, Ottawa, Canada; IVPP – nothosaur, pistosaur and plesiosaur taxa were scored. For fur- Institute for Vertebrate Paleontology and Paleoanthropology, ther information see Supplementary Material. Beijing, China; KHM – Kaikoura Historical Museum, Kaikoura, – New Zealand; MGUAN MuseudeGeologiadaUniversidade Systematic paleontology Agostinho Neto, Luanda, Angola; SMF – Forschungsinstitut und – Naturmuseum Senckenberg, Frankfurt, Germany; TMM Texas SAUROPTERYGIA Owen, 1860 – Memorial Museum, Texas, USA; YPM Yale Peabody Museum, EOSAUROPTERYGIA Rieppel, 1994 New Haven, USA. PLESIOSAURIA de Blainville, 1835 ELASMOSAURIDAE Cope, 1869 sensu Ketchum & Benson, Materials 2010 Cardiocorax mukulu gen. et sp. nov. MGUAN PA103 (Figs 2 and 3), complete pectoral and pelvic gir- Holotype – MGUAN PA103, complete pectoral and pelvic girdle, dle, cervical and dorsal vertebrae, partial forelimb (humerus, cervical and dorsal vertebrae, partial forelimb (humerus, radius and radius and ulna and isolated phalanges) and several dorsal ribs. ulna, and isolated phalanges) and several dorsal ribs. MGUANPA270(Mateusetal.,2012,Figure11),pubis,ischium, Referred specimen – MGAUNPA270isamoreincomplete femur and completely articulated posterior limb. specimen preserving a pelvic girdle and a single hind limb in 110 Downloaded from https://www.cambridge.org/core. IP address: 170.106.33.42, on 23 Sep 2021 at 19:59:54, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/njg.2014.44 Netherlands
Load more

Recommended publications
  • O'keefe, F. R. 2006
    12 Neoteny and the Plesiomorphic Condition of the Plesiosaur Basicranium F. Robin O’Keefe Introduction Historically, the systematics of the Plesiosauria (Reptilia, Sauroptery- gia) were based largely on postcranial characters (Persson, 1963; Brown, 1981). Several factors account for this bias: plesiosaur skulls tend to be del- icate and are often crushed even when preserved, postcranial elements are relatively common and cranial elements are not, lack of knowledge about the relationships of stem-group sauropterygians, and lack of knowledge of plesiosaur cranial anatomy itself. However, recent detailed examinations of plesiosaur cranial anatomy have identified many characters of use in plesiosaur systematics (Brown, 1993; Cruickshank, 1994; Storrs & Taylor, 1996; Storrs, 1997; Carpenter, 1997; Evans, 1999; O’Keefe, 2001, 2004), and the systematics of the group have changed markedly in response (Carpenter, 1997; O’Keefe, 2001, 2004). The work of Rieppel and others has clarified the anatomy and relationships of stem-group sauropterygians (Storrs, 1991; see Rieppel, 2000, for review). This work has laid the anatomic and phylogenetic foundations for a better understanding of ple- siosaur cranial anatomy. The purpose of this paper is to describe the condition of the braincase in stratigraphically early and morphologically primitive plesiosaurs. In- formation on the braincase of plesiomorphic taxa is important because it establishes the polarity of characters occurring in more derived ple- siosaurs. This paper begins with a short review of braincase anatomy in stem-group sauropterygians. Data on braincase morphology of the ple- siomorphic plesiosaur genera Thalassiodracon and Eurycleidus are then presented and interpreted via comparison with other plesiosaurs, stem- group sauropterygians, and stem diapsids (Araeoscelis).
    [Show full text]
  • A New Species of the Sauropsid Reptile Nothosaurus from the Lower Muschelkalk of the Western Germanic Basin, Winterswijk, the Netherlands
    A new species of the sauropsid reptile Nothosaurus from the Lower Muschelkalk of the western Germanic Basin, Winterswijk, The Netherlands NICOLE KLEIN and PAUL C.H. ALBERS Klein, N. and Albers, P.C.H. 2009. A new species of the sauropsid reptile Nothosaurus from the Lower Muschelkalk of the western Germanic Basin, Winterswijk, The Netherlands. Acta Palaeontologica Polonica 54 (4): 589–598. doi:10.4202/ app.2008.0083 A nothosaur skull recently discovered from the Lower Muschelkalk (early Anisian) locality of Winterswijk, The Nether− lands, represents at only 46 mm in length the smallest nothosaur skull known today. It resembles largely the skull mor− phology of Nothosaurus marchicus. Differences concern beside the size, the straight rectangular and relative broad parietals, the short posterior extent of the maxilla, the skull proportions, and the overall low number of maxillary teeth. In spite of its small size, the skull can not unequivocally be interpreted as juvenile. It shows fused premaxillae, nasals, frontals, and parietals, a nearly co−ossified jugal, and fully developed braincase elements, such as a basisphenoid and mas− sive epipterygoids. Adding the specimen to an existing phylogenetic analysis shows that it should be assigned to a new species, Nothosaurus winkelhorsti sp. nov., at least until its juvenile status can be unequivocally verified. Nothosaurus winkelhorsti sp. nov. represents, together with Nothosaurus juvenilis, the most basal nothosaur, so far. Key words: Sauropterygia, Nothosaurus, ontogeny, Anisian, The Netherlands. Nicole Klein [nklein@uni−bonn.de], Steinmann−Institut für Geologie, Mineralogie und Paläontologie, Universtät Bonn, Nußallee 8, 53115 Bonn, Germany; Paul C.H. Albers [[email protected]], Naturalis, Nationaal Natuurhistorisch Museum, Darwinweg 2, 2333 CR Leiden, The Netherlands.
    [Show full text]
  • Carpenter 1999 EL PLESIOSAURIO DE VILLA DE LEYVA (BOYACÁ, COLOMBIA)
    Boletín de Geología Vol. 23, No. 38, Enero-Junio de 2001 Callawayasaurus colombiensis (Welles) Carpenter 1999 EL PLESIOSAURIO DE VILLA DE LEYVA (BOYACÁ, COLOMBIA). ¿UN NUEVO ESPÉCIMEN? Jerez Jaimes, J. H1.; Narváez Parra, E. X1. RESUMEN En los depósitos del Cretácico (Aptiano) de Villa de Leyva se han reportado dos especies de plesiosaurios, un pliosaurio Kronosaurus boyacensis Hampe 1992, y un plesiosaurio Callawayasaurus colombiensis (Welles) Carpenter, 1999 (= Alzadasaurus colombiensis Welles, 1962). Se realiza la determinación de un espécimen de elasmosaurio encontrado por los pobladores de la zona rural de Villa de Leyva en 1999 con base en material fotográfico del mismo, siendo muy probable que corresponda a la especie Callawayasaurus colombiensis (Welles) Carpenter, 1999. Palabras Claves: Cretácico, Plesiosaurios, Villa de Leyva. ABSTRACT In the deposits of the Cretaceous (Aptian) of Villa de Leyva two plesiosaurs species have been reported, a pliosaur Kronosaurus boyacensis Hampe 1992, and a plesiosaur Callawayasaurus colombiensis (Welles) Carpenter, 1999 (= Alzadasaurus colombiensis Welles, 1962). We carried out the determination of elasmosaur specimen found by the inhabitants of the rural area of Villa de Leyva in 1999, on the basis of photographic material of it. Probably it corresponds to the Callawayasaurus colombiensis specie (Welles) Carpenter, 1999. Key Words: Cretaceous, Plesiosaurs, Villa de Leyva. 1Biólogos, Calle 10A # 24-68 Bucaramanga, Santander (Colombia). Correo electrónico: [email protected] Callawayasaurus
    [Show full text]
  • Estimating the Evolutionary Rates in Mosasauroids and Plesiosaurs: Discussion of Niche Occupation in Late Cretaceous Seas
    Estimating the evolutionary rates in mosasauroids and plesiosaurs: discussion of niche occupation in Late Cretaceous seas Daniel Madzia1 and Andrea Cau2 1 Department of Evolutionary Paleobiology, Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland 2 Independent, Parma, Italy ABSTRACT Observations of temporal overlap of niche occupation among Late Cretaceous marine amniotes suggest that the rise and diversification of mosasauroid squamates might have been influenced by competition with or disappearance of some plesiosaur taxa. We discuss that hypothesis through comparisons of the rates of morphological evolution of mosasauroids throughout their evolutionary history with those inferred for contemporary plesiosaur clades. We used expanded versions of two species- level phylogenetic datasets of both these groups, updated them with stratigraphic information, and analyzed using the Bayesian inference to estimate the rates of divergence for each clade. The oscillations in evolutionary rates of the mosasauroid and plesiosaur lineages that overlapped in time and space were then used as a baseline for discussion and comparisons of traits that can affect the shape of the niche structures of aquatic amniotes, such as tooth morphologies, body size, swimming abilities, metabolism, and reproduction. Only two groups of plesiosaurs are considered to be possible niche competitors of mosasauroids: the brachauchenine pliosaurids and the polycotylid leptocleidians. However, direct evidence for interactions between mosasauroids and plesiosaurs is scarce and limited only to large mosasauroids as the Submitted 31 July 2019 predators/scavengers and polycotylids as their prey. The first mosasauroids differed Accepted 18 March 2020 from contemporary plesiosaurs in certain aspects of all discussed traits and no evidence Published 13 April 2020 suggests that early representatives of Mosasauroidea diversified after competitions with Corresponding author plesiosaurs.
    [Show full text]
  • (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]
  • On the Cranial Anatomy of the Polycotylid Plesiosaurs, Including New Material of Polycotylus Latipinnis, Cope, from Alabama F
    Marshall University Marshall Digital Scholar Biological Sciences Faculty Research Biological Sciences 2004 On the cranial anatomy of the polycotylid plesiosaurs, including new material of Polycotylus latipinnis, Cope, from Alabama F. Robin O’Keefe Marshall University, [email protected] Follow this and additional works at: http://mds.marshall.edu/bio_sciences_faculty Part of the Animal Sciences Commons, and the Ecology and Evolutionary Biology Commons Recommended Citation O’Keefe, F. R. 2004. On the cranial anatomy of the polycotylid plesiosaurs, including new material of Polycotylus latipinnis, Cope, from Alabama. Journal of Vertebrate Paleontology 24(2):326–340. This Article is brought to you for free and open access by the Biological Sciences at Marshall Digital Scholar. It has been accepted for inclusion in Biological Sciences Faculty Research by an authorized administrator of Marshall Digital Scholar. For more information, please contact [email protected], [email protected]. ON THE CRANIAL ANATOMY OF THE POLYCOTYLID PLESIOSAURS, INCLUDING NEW MATERIAL OF POLYCOTYLUS LATIPINNIS, COPE, FROM ALABAMA F. ROBIN O’KEEFE Department of Anatomy, New York College of Osteopathic Medicine, Old Westbury, New York 11568, U.S.A., [email protected] ABSTRACT—The cranial anatomy of plesiosaurs in the family Polycotylidae (Reptilia: Sauropterygia) has received renewed attention recently because various skull characters are thought to indicate plesiosauroid, rather than plio- sauroid, affinities for this family. New data on the cranial anatomy of polycotylid plesiosaurs is presented, and is shown to compare closely to the structure of cryptocleidoid plesiosaurs. The morphology of known polycotylid taxa is reported and discussed, and a preliminary phylogenetic analysis is used to establish ingroup relationships of the Cryptocleidoidea.
    [Show full text]
  • Morphologic and Ontogenetic Patterns in Elasmosaur Neck Length, with Comments on the Taxonomic Utility of Neck Length Variables F
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Collection Of Biostatistics Research Archive Marshall University Marshall Digital Scholar Biological Sciences Faculty Research Biological Sciences 6-1-2006 Morphologic and Ontogenetic Patterns in Elasmosaur Neck Length, with Comments on the Taxonomic Utility of Neck Length Variables F. Robin O’Keefe Marshall University, [email protected] Norton Hiller Follow this and additional works at: http://mds.marshall.edu/bio_sciences_faculty Part of the Aquaculture and Fisheries Commons, and the Ecology and Evolutionary Biology Commons Recommended Citation O’Keefe FR, Hiller N (2006) Morphologic and ontogenetic patterns in elasmosaur neck length, with comments on the taxonomic utility of neck length variables. Paludicola 5:206–229. This Article is brought to you for free and open access by the Biological Sciences at Marshall Digital Scholar. It has been accepted for inclusion in Biological Sciences Faculty Research by an authorized administrator of Marshall Digital Scholar. For more information, please contact [email protected]. Paludicola 5(4):206-229 June 2006 by the Rochester Institute of Vertebrate Paleontology MORPHOLOGIC AND ONTOGENETIC PATTERNS IN ELASMOSAUR NECK LENGTH, WITH COMMENTS ON THE TAXONOMIC UTILITY OF NECK LENGTH VARIABLES F. Robin O'Keefe1 and Norton Hiller2 1Department of Anatomy, NYCOM 2 rm. 321, New York College of Osteopathic Medicine Old Westbury, New York 11568, [email protected] 2Canterbury Museum, Rolleston Avenue Christchurch, 8001 New Zealand, [email protected] ABSTRACT Elasmosaur cervical vertebrae are common fossils, but their taxonomic utility is limited due to a lack of understanding concerning their shape within and among taxa.
    [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]
  • Cranial Anatomy and Taxonomy of Dolichorhynchops Bonneri New
    Marshall University Marshall Digital Scholar Biological Sciences Faculty Research Biological Sciences 2008 Cranial anatomy and taxonomy of Dolichorhynchops bonneri new combination, a polycotylid (Sauropterygia: Plesiosauria) from the Pierre Shale of Wyoming and South Dakota F. Robin O’Keefe Marshall University, [email protected] Follow this and additional works at: http://mds.marshall.edu/bio_sciences_faculty Part of the Animal Sciences Commons, and the Ecology and Evolutionary Biology Commons Recommended Citation O'Keefe, F. R. (2008). Cranial anatomy and taxonomy of Dolichorhynchops bonneri new combination, a polycotylid (Sauropterygia: Plesiosauria) from the Pierre Shale of Wyoming and South Dakota. Journal of Vertebrate Paleontology, 28(3), 664-676. This Article is brought to you for free and open access by the Biological Sciences at Marshall Digital Scholar. It has been accepted for inclusion in Biological Sciences Faculty Research by an authorized administrator of Marshall Digital Scholar. For more information, please contact [email protected], [email protected]. CRANIAL ANATOMY AND TAXONOMY OF DOLICHORHYNCHOPS BONNERI NEW COMBINATION, A POLYCOTYLID (SAUROPTERYGIA: PLESIOSAURIA) FROM THE PIERRE SHALE OF WYOMING AND SOUTH DAKOTA F. ROBIN O’KEEFE ABSTRACT The taxonomic identity of two well-preserved polycotylid plesiosaur skeletons from the Pierre Shale of far northern Wyoming and southern South Dakota has been controversial since their discovery. Originally referred to Dolichorhynchops osborni, the material was almost immediate-ly christened Trinacromerum bonneri Adams 1997; more recently the material has been referred to Polycotylus. Recent preparation of the well-preserved skull of one specimen permits detailed examination of the cranial morphology of this animal for the first time, and allows for its inclusion in a cladistic analysis of the Polycotylidae.
    [Show full text]
  • Remarks on the Pectoral Girdle of Hydrotherosaurus Alexandrae (Plesiosauria: Elasmosauridae)
    Sachs, Pectoral girdle Hydrotherosaurus alexandrae www.PalArch.nl, vertebrate palaeontology, 4, 1, (2005) Remarks on the pectoral girdle of Hydrotherosaurus alexandrae (Plesiosauria: Elasmosauridae) S. Sachs Institut für Paläontologie Freie Universität Berlin, Malteser Strasse 74–100 Haus D,12249 Berlin, Germany [email protected] ISSN 1567–2158 3 figures Abstract The pectoral girdle of Hydrotherosaurus alexandrae Welles 1943, an elasmosaurid plesiosaur from the Upper Cretaceous (Maastrichtian) of California, USA, is redescribed. Some differences to the reconstruction presented in the original description, as well as newly discovered features of the pectoral girdle are discussed and a new reconstruction is provided. Contents 1. Introduction 2. Description 2.1. General comments 2.2. Scapula 2.3. Coracoid 3. Discussion 4. Conclusions 5. Acknowledgements 6. References Abbreviations AMNH American Museum of Natural History, New York, USA RMF Richmond Marine Fossil Museum, Richmond, Australia SDSM South Dakota School of Mines, Rapid City, USA UCMP University of California Museum of Paleontology, Berkeley, USA PalArch Foundation Sachs, Pectoral girdle Hydrotherosaurus alexandrae www.PalArch.nl, vertebrate palaeontology, 4, 1, (2005) 1. Introduction In his description of Hydrotherosaurus alexandrae, an elasmosaurid plesiosaur from the Upper Cretaceous (Maastrichtian, Moreno Formation) of Fresno County, California, Welles (1943) presented an unusual restoration of the pectoral girdle with asymmetrical coracoids. At the time, the about 8 m long, almost complete skeleton of the type specimen (UCMP 33912) had already been mounted at the University California Museum of Paleontology at Berkeley (UCMP). The exhibit was taken down in the 1960s and apparently has not been studied since. The skeleton was examined by the author during a visit to the UCMP in 2001 and some differences in the description and interpretation by Welles (1943) became apparent.
    [Show full text]
  • Morphologic and Ontogenetic Patterns in Elasmosaur Neck Length, with Comments on the Taxonomic Utility of Neck Length Variables F
    Marshall University Marshall Digital Scholar Biological Sciences Faculty Research Biological Sciences 6-2006 Morphologic and Ontogenetic Patterns in Elasmosaur Neck Length, with Comments on the Taxonomic Utility of Neck Length Variables F. Robin O’Keefe Marshall University, [email protected] Norton Hiller Follow this and additional works at: http://mds.marshall.edu/bio_sciences_faculty Part of the Aquaculture and Fisheries Commons, and the Ecology and Evolutionary Biology Commons Recommended Citation O’Keefe FR, Hiller N (2006) Morphologic and ontogenetic patterns in elasmosaur neck length, with comments on the taxonomic utility of neck length variables. Paludicola 5:206–229. This Article is brought to you for free and open access by the Biological Sciences at Marshall Digital Scholar. It has been accepted for inclusion in Biological Sciences Faculty Research by an authorized administrator of Marshall Digital Scholar. For more information, please contact [email protected], [email protected]. Paludicola 5(4):206-229 June 2006 by the Rochester Institute of Vertebrate Paleontology MORPHOLOGIC AND ONTOGENETIC PATTERNS IN ELASMOSAUR NECK LENGTH, WITH COMMENTS ON THE TAXONOMIC UTILITY OF NECK LENGTH VARIABLES F. Robin O'Keefe1 and Norton Hiller2 1Department of Anatomy, NYCOM 2 rm. 321, New York College of Osteopathic Medicine Old Westbury, New York 11568, [email protected] 2Canterbury Museum, Rolleston Avenue Christchurch, 8001 New Zealand, [email protected] ABSTRACT Elasmosaur cervical vertebrae are common fossils, but their taxonomic utility is limited due to a lack of understanding concerning their shape within and among taxa. In this paper, we analyze data from complete elasmosaur necks in an attempt to quantify and understand the variation in centrum dimensions.
    [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]