DOCSLIB.ORG

The Postcranial Skeleton of Temnospondyls

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Postcranial Skeleton of Temnospondyls Published as: Pawley, K. in press. The postcranial skeleton of Trimerorhachis insignis Cope 1878 81 (Temnospondyli: Trimerorhachidae) a plesiomorphic, secondarily aquatic temnospondyl from the Lower Permian of North America. Journal of Paleontology. Copyright © 2006 The Paleontological Society CHAPTER 3. THE POSTCRANIAL SKELETON OF TRIMERORHACHIS INSIGNIS COPE, 1878 (TEMNOSPONDYLI: TRIMERORHACHIDAE): A PLESIOMORPHIC TEMNOSPONDYL FROM THE LOWER PERMIAN OF NORTH AMERICA Abstract. The postcranial skeleton of the Lower Permian temnospondyl Trimerorhachis insignis Cope, 1878 is described and figured in detail. Postcranial adaptations for an aquatic existence in T. insignis include the extensive ventral expansion of the interclavicle and clavicles, and poorly ossified ends of the endochondral bones. The endochondral postcranial skeleton of T. insignis is paedomorphic through the process of neoteny, retaining an osteologically immature condition throughout morphogenesis. The endochondral postcranial elements display progressive morphological changes that do not stabilise in larger specimens, indicating indeterminate growth, with a correlation between size and degree of ossification. Some postcranial characteristics are present only in later morphogenetic stages of T. insignis. Within the Temnospondyli, the postcranial skeleton of T. insignis is most similar to that of other members of the Dvinosauria. The morphology of the postcranial skeleton of T. insignis is consistent with a phylogenetic position more derived than the basal temnospondyls Balanerpeton woodi and Dendrerpeton acadianum, but less derived than the Euskelia plus Stereospondylomorpha. A sister-taxon relationship between the Dvinosauria and brachyopoids is not supported by postcranial characteristics of T. insignis. Characteristics that develop last in morphogenesis in temnospondyls, and are consequently only present in well-ossified, morphogenetically mature temnospondyls, are absent in T. insignis due to paedomorphosis. Otherwise, the postcranial skeletons of T. insignis and other aquatic temnospondyls are similar to that of terrestrial temnospondyls, supporting the hypothesis that aquatic temnospondyls had terrestrial ancestors, and are thus secondarily aquatic. INTRODUCTION Trimerorhachis insignis Cope, 1878 is a medium-sized, aquatically adapted temnospondyl from the lower Permian of North America. It is the most abundant temnospondyl in the Lower Permian red beds of north-central Texas (Romer, 1928; Olson, 1956). Temnospondyls are the most numerous and diverse group of the archaic Palaeozoic ‘labyrinthodont’ amphibians. Among temnospondyls the postcranial skeleton varies from heavily ossified, with obvious terrestrial adaptations in the stratigraphically oldest taxa, Balanerpeton woodi (Milner and Sequeira, 1994) and Dendrerpeton acadianum Owen, 1853 (Carroll, 1967; Holmes et al., 1998), to poorly ossified, paedomorphic (sensu McNamara, 1986), and aquatically adapted in some of the Permian taxa, including Trimerorhachis insignis, and most of the Mesozoic taxa (Pawley and Warren, 2004). Trimerorhachis insignis is a member of the basal temnospondyl clade Dvinosauria Yates and Warren, 2000. The Dvinosauria, as defined by Yates and Warren (2000), also includes other trimerorhachoids, dvinosaurs, and tupilakosaurs. Traditionally, the literature neglects the postcranial skeletons of temnospondyls. While most of these have associated postcranial material (when described at all), illustrations of individual elements are rarely adequate for complete inter-taxon comparisons, including cladistic analysis. 82 K. PAWLEY PHD THESIS The postcranial skeletons of plesiomorphic temnospondyls are those most in need of description, both for understanding the evolution of the temnospondyl postcranial skeleton and assessing the phylogenetic relationships of temnospondyls within other early tetrapod groups. As part of a more inclusive long-term study of the temnospondyl postcranial skeleton, a comprehensive description of the postcranial elements of a member of poorly known temnospondyl clades was undertaken in order to facilitate assessment of the phylogenetic distribution of postcranial characteristics, and to tease out homoplasy associated with both aquatic and terrestrial adaptations. The abundant, well- preserved remains of T. insignis make it an ideal subject for these purposes. Phylogenetic position All recent phylogenetic assessments involving T. insignis have relied almost entirely on cranial characteristics. The position of the Dvinosauria within the Temnospondyli is contentious: the analysis of Yates and Warren (2000) placed the Dvinosauria as derived sister taxon to the Stereospondylomorpha, whereas Ruta et al. (2003) found that the Dvinosauria were the most basal clade within the Temnospondyli. Most controversially, an ongoing debate has ensued as to whether the Dvinosauria, or the more derived stereospondyls, is the sister taxon to the Brachyopoidea (summarized in Damiani, 2003). Within the Dvinosauria, the postcranial skeleton of Trimerorhachis insignis is the most suitable for description because abundant material is available for study. The poorly ossified articulation surfaces of the endochondral postcranial elements limit the use of T. insignis for comparative purposes; however, descriptions of plesiomorphic temnospondyls are useful because our knowledge of the postcranial skeletons of these taxa is limited. The aim of this description is to improve our understanding of the postcranial skeleton of T. insignis, document the morphogenetic changes that occur, and to describe potential characteristics for use in future phylogenetic analyses. Aquatic adaptations in temnospondyls Trimerorhachis insignis, along with many other temnospondyls, displays adaptations for an obligatorily aquatic lifestyle such as lateral line sulci, ossified ceratobranchials, enlarged, anteriorly expanded interclavicle and clavicles, and a poorly ossified endochondral postcranial skeleton with small limbs. This type of postcranial morphology is also characteristic of all other members of the Dvinosauria and the more derived members of the mainly Mesozoic Stereospondyli. There has been much debate over the last two decades involving temnospondyls, concerning the origin of terrestrial vertebrates (summarized in Clack, 2002a; Long and Gordon, 2004), the phylogenetic relationships of early tetrapods, and the origin of modern lissamphibians and amniotes (summarized in Ruta et al., 2003; Schoch and Milner, 2004). From a phylogenetic and functional point of view, it is important to define the differences between the postcranial skeletons of primarily aquatic basal tetrapods (no terrestrial ancestors) such as Acanthostega gunnari Jarvik, 1952 (Coates and Clack, 1990, 1991; Coates, 1996) and secondarily aquatic temnospondyls (Watson, 1919), including T. insignis. Previous descriptions of Trimerorhachis insignis The skull of T. insignis was first described by Cope (1878), further descriptions were undertaken by Cope (1884), Case (1911a; 1935) and Cope and Matthew (1915). Nilsson CHAPTER 3: POSTCRANIAL SKELETON OF TRIMERORHACHIS 83 (1944) described the mandible, Lombard and Bolt (1988) the stapes, and Watson (1956) and Schoch (1999b) the braincase. Previous partial descriptions of postcranial material of the genus Trimerorhachis Cope, 1878 include those of T. insignis by Cope (1884), Case (1911a; 1935), Cope and Matthew (1915), Williston (1915a), and Shishkin (2000), and of T. sandovalensis (Berman and Reisz, 1980). Williston (1916) gave a brief account of an almost complete, but only partially prepared, skeleton of T. insignis, which was revised by Olson (1979). Overlapping dorsal scales were described by Colbert (1955) and osteoderms and ossified ceratobranchials by Olson (1979). Cope (1878) first described Trimerorhachis insignis, and erected the Trimerorhachidae (Cope, 1884). Olson (1956) revised Trimerorhachis, synonymising all previous species except T. mesops Cope, 1896 (Clear Fork Formation) with the holotypic species, and created a new species, T. rogersii (early Choza Formation). While not revising the genus in any formal sense, Berman and Reisz (1980) considered the two latter species indistinguishable from the holotypic species, and described a new species, T. sandovalensis, from the Abo Formation of New Mexico. Taxa within the Dvinosauria with associated postcranial material The only other Trimerorhachis species with associated postcranial material is T. sandovalensis (Berman and Reisz, 1980). Most other taxa within the Dvinosauria have associated postcranial material, including the trimerorhachoids Neldasaurus wrightae (Chase, 1965), Acroplous vorax (Hotton, 1959; Coldiron, 1978; Foreman, 1990) and Isodectes (Eobrachyops, Saurerpeton) obtusus Sequeira, 1998 (Watson, 1956); the dvinosaur Dvinosaurus spp. Amalitzky, 1921 (Sushkin, 1936; Bystrow, 1938; Nikitin, 1995, 1997; Gubin, 2004); and the tupilakosaurs Thabanchuia oomie (Warren, 1998b), Tupilakosaurus spp. (Nielsen, 1954; Shishkin, 1961, 1973), and Kourerpeton bradyi (Olson and Lammers, 1976). While most of these have associated postcranial material, the descriptions lack the detail necessary for comprehensive comparison. Stratigraphic distribution Trimerorhachis insignis is found throughout the nonmarine Wolfcampian Lower Permian, from the Wichita to the Clear Fork formations (stratigraphy revised after Hentz and Brown, 1987), to the middle of the San Angelo Formation of the Pease River Group (Olson and Vaughn, 1970; Parrish, 1978).
Load more

Recommended publications
  • New Permian Fauna from Tropical Gondwana
    ARTICLE Received 18 Jun 2015 | Accepted 18 Sep 2015 | Published 5 Nov 2015 DOI: 10.1038/ncomms9676 OPEN New Permian fauna from tropical Gondwana Juan C. Cisneros1,2, Claudia Marsicano3, Kenneth D. Angielczyk4, Roger M. H. Smith5,6, Martha Richter7, Jo¨rg Fro¨bisch8,9, Christian F. Kammerer8 & Rudyard W. Sadleir4,10 Terrestrial vertebrates are first known to colonize high-latitude regions during the middle Permian (Guadalupian) about 270 million years ago, following the Pennsylvanian Gondwanan continental glaciation. However, despite over 150 years of study in these areas, the bio- geographic origins of these rich communities of land-dwelling vertebrates remain obscure. Here we report on a new early Permian continental tetrapod fauna from South America in tropical Western Gondwana that sheds new light on patterns of tetrapod distribution. Northeastern Brazil hosted an extensive lacustrine system inhabited by a unique community of temnospondyl amphibians and reptiles that considerably expand the known temporal and geographic ranges of key subgroups. Our findings demonstrate that tetrapod groups common in later Permian and Triassic temperate communities were already present in tropical Gondwana by the early Permian (Cisuralian). This new fauna constitutes a new biogeographic province with North American affinities and clearly demonstrates that tetrapod dispersal into Gondwana was already underway at the beginning of the Permian. 1 Centro de Cieˆncias da Natureza, Universidade Federal do Piauı´, 64049-550 Teresina, Brazil. 2 Programa de Po´s-Graduac¸a˜o em Geocieˆncias, Departamento de Geologia, Universidade Federal de Pernambuco, 50740-533 Recife, Brazil. 3 Departamento de Cs. Geologicas, FCEN, Universidad de Buenos Aires, IDEAN- CONICET, C1428EHA Ciudad Auto´noma de Buenos Aires, Argentina.
    [Show full text]
  • Stuttgarter Beiträge Zur Naturkunde
    S^5 ( © Biodiversity Heritage Library, http://www.biodiversitylibrary.org/; www.zobodat.at Stuttgarter Beiträge zur Naturkunde Serie B (Geologie und Paläontologie) Herausgeber: Staatliches Museum für Naturkunde, Rosenstein 1, D-70191 Stuttgart Stuttgarter Beitr. Naturk. Ser. B Nr. 278 175 pp., 4pls., 54figs. Stuttgart, 30. 12. 1999 Comparative osteology oi Mastodonsaurus giganteus (Jaeger, 1828) from the Middle Triassic (Lettenkeuper: Longobardian) of Germany (Baden-Württemberg, Bayern, Thüringen) By Rainer R. Schoch, Stuttgart With 4 plates and 54 textfigures Abstract Mastodonsaurus giganteus, the most abundant and giant amphibian of the German Letten- keuper, is revised. The study is based on the excellently preserved and very rieh material which was excavated during road construction in 1977 near Kupferzeil, Northern Baden- Württemberg. It is shown that there exists only one diagnosable species of Mastodonsaurus, to which all Lettenkeuper material can be attributed. All finds from other horizons must be referred to as Mastodonsauridae gen. et sp. indet. because of their fragmentary Status. A sec- ond, definitely diagnostic genus of this family is Heptasaurus from the higher Middle and Upper Buntsandstein. Finally a diagnosis of the family Mastodonsauridae is provided. Ä detailed osteological description of Mastodonsaurus giganteus reveals numerous un- known or formerly inadequately understood features, yielding data on various hitherto poor- ly known regions of the skeleton. The sutures of the skull roof, which could be studied in de- tail, are significantly different from the schemes presented by previous authors. The endocra- nium and mandible are further points of particular interest. The palatoquadrate contributes a significant part to the formation of the endocranium by an extensive and complicated epi- pterygoid.
    [Show full text]
  • Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha)
    Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha) by Richard Kissel A thesis submitted in conformity with the requirements for the degree of doctor of philosophy Graduate Department of Ecology & Evolutionary Biology University of Toronto © Copyright by Richard Kissel 2010 Morphology, Phylogeny, and Evolution of Diadectidae (Cotylosauria: Diadectomorpha) Richard Kissel Doctor of Philosophy Graduate Department of Ecology & Evolutionary Biology University of Toronto 2010 Abstract Based on dental, cranial, and postcranial anatomy, members of the Permo-Carboniferous clade Diadectidae are generally regarded as the earliest tetrapods capable of processing high-fiber plant material; presented here is a review of diadectid morphology, phylogeny, taxonomy, and paleozoogeography. Phylogenetic analyses support the monophyly of Diadectidae within Diadectomorpha, the sister-group to Amniota, with Limnoscelis as the sister-taxon to Tseajaia + Diadectidae. Analysis of diadectid interrelationships of all known taxa for which adequate specimens and information are known—the first of its kind conducted—positions Ambedus pusillus as the sister-taxon to all other forms, with Diadectes sanmiguelensis, Orobates pabsti, Desmatodon hesperis, Diadectes absitus, and (Diadectes sideropelicus + Diadectes tenuitectes + Diasparactus zenos) representing progressively more derived taxa in a series of nested clades. In light of these results, it is recommended herein that the species Diadectes sanmiguelensis be referred to the new genus
    [Show full text]
  • Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships
    438 Article 438 by Saswati Bandyopadhyay1* and Sanghamitra Ray2 Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships 1Geological Studies Unit, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India; email: [email protected] 2Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur 721302, India; email: [email protected] *Corresponding author (Received : 23/12/2018; Revised accepted : 11/09/2019) https://doi.org/10.18814/epiiugs/2020/020028 The twelve Gondwanan stratigraphic horizons of many extant lineages, producing highly diverse terrestrial vertebrates India have yielded varied vertebrate fossils. The oldest in the vacant niches created throughout the world due to the end- Permian extinction event. Diapsids diversified rapidly by the Middle fossil record is the Endothiodon-dominated multitaxic Triassic in to many communities of continental tetrapods, whereas Kundaram fauna, which correlates the Kundaram the non-mammalian synapsids became a minor components for the Formation with several other coeval Late Permian remainder of the Mesozoic Era. The Gondwana basins of peninsular horizons of South Africa, Zambia, Tanzania, India (Fig. 1A) aptly exemplify the diverse vertebrate faunas found Mozambique, Malawi, Madagascar and Brazil. The from the Late Palaeozoic and Mesozoic. During the last few decades much emphasis was given on explorations and excavations of Permian-Triassic transition in India is marked by vertebrate fossils in these basins which have yielded many new fossil distinct taxonomic shift and faunal characteristics and vertebrates, significant both in numbers and diversity of genera, and represented by small-sized holdover fauna of the providing information on their taphonomy, taxonomy, phylogeny, Early Triassic Panchet and Kamthi fauna.
    [Show full text]
  • The Scapulocoracoid of an Early Triassic Stem−Frog from Poland
    The scapulocoracoid of an Early Triassic stem−frog from Poland MAGDALENA BORSUK−BIAŁYNICKA and SUSAN E. EVANS Borsuk−Białynicka, M. and Evans, S.E. 2002. The scapulocoracoid of an Early Triassic stem−frog from Poland. Acta Palaeontologica Polonica 47 (1): 79–96. The scapulocoracoid of Czatkobatrachus polonicus Evans and Borsuk−Białynicka, 1998, a stem−frog from the Early Tri− assic karst locality of Czatkowice (Southern Poland), is described. The overall type of scapulocoracoid is plesiomorphic, but the subcircular shape and laterally oriented glenoid is considered synapomorphic of Salientia. The supraglenoid fora− men is considered homologous to the scapular cleft of the Anura. In Czatkobatrachus, the supraglenoid foramen occupies an intermediate position between that of the early tetrapod foramen and the scapular cleft of Anura. The cleft scapula is probably synapomorphic for the Anura. In early salientian phylogeny, the shift in position of the supraglenoid foramen may have been associated with an anterior rotation of the forelimb. This change in position of the forelimb may reflect an evolutionary shift from a mainly locomotory function to static functions (support, balance, eventually shock−absorption). Laterally extended limbs may have been more effective than posterolateral ones in absorbing landing stresses, until the specialised shock−absorption pectoral mechanism of crown−group Anura had developed. The glenoid shape and position, and the slender scapular blade, of Czatkobatrachus, in combination with the well−ossified joint surfaces on the humerus and ulna, all support a primarily terrestrial rather than aquatic mode of life. The new Polish material also permits clarifica− tion of the pectoral anatomy of the contemporaneous Madagascan genus Triadobatrachus.
    [Show full text]
  • Phylogeny and Evolution of the Dissorophoid Temnospondyls
    Journal of Paleontology, 93(1), 2019, p. 137–156 Copyright © 2018, The Paleontological Society. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. 0022-3360/15/0088-0906 doi: 10.1017/jpa.2018.67 The putative lissamphibian stem-group: phylogeny and evolution of the dissorophoid temnospondyls Rainer R. Schoch Staatliches Museum für Naturkunde, Rosenstein 1, D-70191 Stuttgart, Germany 〈[email protected]〉 Abstract.—Dissorophoid temnospondyls are widely considered to have given rise to some or all modern amphibians (Lissamphibia), but their ingroup relationships still bear major unresolved questions. An inclusive phylogenetic ana- lysis of dissorophoids gives new insights into the large-scale topology of relationships. Based on a TNT 1.5 analysis (33 taxa, 108 characters), the enigmatic taxon Perryella is found to nest just outside Dissorophoidea (phylogenetic defintion), but shares a range of synapomorphies with this clade. The dissorophoids proper are found to encompass a first dichotomy between the largely paedomorphic Micromelerpetidae and all other taxa (Xerodromes). Within the latter, there is a basal dichotomy between the large, heavily ossified Olsoniformes (Dissorophidae + Trematopidae) and the small salamander-like Amphibamiformes (new taxon), which include four clades: (1) Micropholidae (Tersomius, Pasawioops, Micropholis); (2) Amphibamidae sensu stricto (Doleserpeton, Amphibamus); (3) Branchiosaur- idae (Branchiosaurus, Apateon, Leptorophus, Schoenfelderpeton); and (4) Lissamphibia. The genera Platyrhinops and Eos- copus are here found to nest at the base of Amphibamiformes. Represented by their basal-most stem-taxa (Triadobatrachus, Karaurus, Eocaecilia), lissamphibians nest with Gerobatrachus rather than Amphibamidae, as repeatedly found by former analyses.
    [Show full text]
  • Physical and Environmental Drivers of Paleozoic Tetrapod Dispersal Across Pangaea
    ARTICLE https://doi.org/10.1038/s41467-018-07623-x OPEN Physical and environmental drivers of Paleozoic tetrapod dispersal across Pangaea Neil Brocklehurst1,2, Emma M. Dunne3, Daniel D. Cashmore3 &Jӧrg Frӧbisch2,4 The Carboniferous and Permian were crucial intervals in the establishment of terrestrial ecosystems, which occurred alongside substantial environmental and climate changes throughout the globe, as well as the final assembly of the supercontinent of Pangaea. The fl 1234567890():,; in uence of these changes on tetrapod biogeography is highly contentious, with some authors suggesting a cosmopolitan fauna resulting from a lack of barriers, and some iden- tifying provincialism. Here we carry out a detailed historical biogeographic analysis of late Paleozoic tetrapods to study the patterns of dispersal and vicariance. A likelihood-based approach to infer ancestral areas is combined with stochastic mapping to assess rates of vicariance and dispersal. Both the late Carboniferous and the end-Guadalupian are char- acterised by a decrease in dispersal and a vicariance peak in amniotes and amphibians. The first of these shifts is attributed to orogenic activity, the second to increasing climate heterogeneity. 1 Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK. 2 Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, 10115 Berlin, Germany. 3 School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK. 4 Institut
    [Show full text]
  • 3D Computational Mechanics Elucidate the Evolutionary Implications of Orbit Position and Size Diversity of Early Amphibians
    RESEARCH ARTICLE 3D Computational Mechanics Elucidate the Evolutionary Implications of Orbit Position and Size Diversity of Early Amphibians Jordi Marcé-Nogué1,2*, Josep Fortuny1,2, Soledad De Esteban-Trivigno2,3, Montserrat Sánchez1, Lluís Gil1, Àngel Galobart2 1 Universitat Politècnica de Catalunya–BarcelonaTech, Terrassa, Spain, 2 Institut Català de Paleontologia Miquel Crusafont, Cerdanyola del Vallés, Spain, 3 Transmitting Science, Piera, Spain * [email protected] Abstract For the first time in vertebrate palaeontology, the potential of joining Finite Element Analysis (FEA) and Parametrical Analysis (PA) is used to shed new light on two different cranial OPEN ACCESS parameters from the orbits to evaluate their biomechanical role and evolutionary patterns. Citation: Marcé-Nogué J, Fortuny J, De Esteban- The early tetrapod group of Stereospondyls, one of the largest groups of Temnospondyls is Trivigno S, Sánchez M, Gil L, Galobart À (2015) 3D used as a case study because its orbits position and size vary hugely within the members of Computational Mechanics Elucidate the Evolutionary Implications of Orbit Position and Size Diversity of this group. An adult skull of Edingerella madagascariensis was analysed using two different Early Amphibians. PLoS ONE 10(6): e0131320. cases of boundary and loading conditions in order to quantify stress and deformation doi:10.1371/journal.pone.0131320 response under a bilateral bite and during skull raising. Firstly, the variation of the original Editor: Pasquale Raia, University of Naples, ITALY geometry of its orbits was introduced in the models producing new FEA results, allowing the Received: October 15, 2014 exploration of the ecomorphology, feeding strategy and evolutionary patterns of these top predators.
    [Show full text]
  • Anatomy and Relationships of the Triassic Temnospondyl Sclerothorax
    Anatomy and relationships of the Triassic temnospondyl Sclerothorax RAINER R. SCHOCH, MICHAEL FASTNACHT, JÜRGEN FICHTER, and THOMAS KELLER Schoch, R.R., Fastnacht, M., Fichter, J., and Keller, T. 2007. Anatomy and relationships of the Triassic temnospondyl Sclerothorax. Acta Palaeontologica Polonica 52 (1): 117–136. Recently, new material of the peculiar tetrapod Sclerothorax hypselonotus from the Middle Buntsandstein (Olenekian) of north−central Germany has emerged that reveals the anatomy of the skull and anterior postcranial skeleton in detail. Despite differences in preservation, all previous plus the new finds of Sclerothorax are identified as belonging to the same taxon. Sclerothorax is characterized by various autapomorphies (subquadrangular skull being widest in snout region, ex− treme height of thoracal neural spines in mid−trunk region, rhomboidal interclavicle longer than skull). Despite its pecu− liar skull roof, the palate and mandible are consistent with those of capitosauroid stereospondyls in the presence of large muscular pockets on the basal plate, a flattened edentulous parasphenoid, a long basicranial suture, a large hamate process in the mandible, and a falciform crest in the occipital part of the cheek. In order to elucidate the phylogenetic position of Sclerothorax, we performed a cladistic analysis of 18 taxa and 70 characters from all parts of the skeleton. According to our results, Sclerothorax is nested well within the higher stereospondyls, forming the sister taxon of capitosauroids. Palaeobiologically, Sclerothorax is interesting for its several characters believed to correlate with a terrestrial life, although this is contrasted by the possession of well−established lateral line sulci. Key words: Sclerothorax, Temnospondyli, Stereospondyli, Buntsandstein, Triassic, Germany.
    [Show full text]
  • Jahresbericht 2013
    Staatliches Museum für Naturkunde Stuttgart Jahresbericht Sammeln Bewahren Forschen Vermitteln 13 Impressum Herausgeber Prof. Dr. Johanna Eder Direktorin Staatliches Museum für Naturkunde Stuttgart Rosenstein 1 70191 Stuttgart Redaktion M.Sc. Lena Kempener Staatliches Museum für Naturkunde Stuttgart Jahresbericht/Dokumentarische Ausgabe ISSN 2191-7817 Berichtsjahr 2013, erschienen 2014 Copyright Diese Zeitschrift ist urheberrechtlich geschützt. Eine Verwertung ist nur mit schriftlicher Genehmi- gung des Herausgebers gestattet. Bildnachweis Coverfotos: U.Schmid (o.l.), U. Stübler (o.r.), S. Leidenroth (u.l.), M. Wahler (u.r.) Inhaltsverzeichnis 2 INHALTSVERZEICHNIS EDITORIAL 4 1 FORSCHUNG 6 1.1 Forschungsprojekte 6 1.1.1 Drittmittel-finanziert 6 1.1.2 Nicht Drittmittel-finanziert 8 1.2 Umfangreiche Freilandarbeiten, Grabungen 13 1.3 Studienaufenthalte 14 1.4 Tagungsbeiträge 15 1.4.1 International 15 1.4.2 National 17 1.5 Sonstige wissenschaftliche Vorträge 18 1.6 Organisation von Tagungen und Workshops 19 1.7 Organisierte wissenschaftliche Exkursionen 19 1.8 Gastforscher 20 1.8.1 National 20 1.8.2 International 22 2 SAMMLUNG UND BIBLIOTHEK 24 2.1 Bedeutende Sammlungsarbeiten 24 2.1.1 Wissenschaftliche Arbeiten 24 2.1.2 Präparatorische und konservatorische Arbeiten 25 2.1.3 Elektronische Sammlungserfassung 28 2.2 Bedeutende Sammlungszugänge 28 2.3 Führungen hinter die Kulissen 29 2.4 Bibliothek und Archiv 30 3 BILDUNG UND ÖFFENTLICHKEITSARBEIT 30 3.1 Führungen und Projekte 30 3.1.1 Dauerausstellung 30 3.1.2 Sonderausstellung 31 3.1.3 Neues
    [Show full text]
  • Marzola Et Al 2017 Cyclotosaurus Greenland
    Journal of Vertebrate Paleontology e1303501 (14 pages) Ó by the Society of Vertebrate Paleontology DOI: 10.1080/02724634.2017.1303501 ARTICLE CYCLOTOSAURUS NARASERLUKI, SP. NOV., A NEW LATE TRIASSIC CYCLOTOSAURID (AMPHIBIA, TEMNOSPONDYLI) FROM THE FLEMING FJORD FORMATION OF THE JAMESON LAND BASIN (EAST GREENLAND) MARCO MARZOLA *,1,2,3,4 OCTAVIO MATEUS 1,3 NEIL H. SHUBIN5 and LARS B. CLEMMENSEN 2 1GeoBioTec, Departamento de Ciencias^ da Terra, Faculdade de Ciencias^ e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, [email protected]; [email protected]; 2Institut for Geovidenskab og Naturforvaltning (IGN), Det Natur-og Biovidenskabelige Fakultet, Københavns Universitet, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark, [email protected]; 3Museu da Lourinha,~ Rua Joao~ Luıs de Moura, 95, 2530-158 Lourinha,~ Portugal; 4Geocenter Møns Klint, Stengardsvej 8, DK-4751 Borre, Denmark; 5Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60637, U.S.A., [email protected] ABSTRACT—Cyclotosaurus naraserluki, sp. nov., is a new Late Triassic capitosaurid amphibian from lacustrine deposits in the Fleming Fjord Formation of the Jameson Land Basin in Greenland. It is based on a fairly complete and well-preserved skull associated with two vertebral intercentra. Previously reported as Cyclotosaurus cf. posthumus, C. naraserluki is unique among cyclotosaurs for having the postorbitals embaying the supratemporals posteromedially. The anterior palatal vacuity presents an autapomorphic complete subdivision by a wide medial premaxillary-vomerine bony connection. The parasphenoid projects between the pterygoids and the exoccipitals, preventing a suture between the two, a primitive condition shared with Rhinesuchidae, Eryosuchus, and Kupferzellia.
    [Show full text]
  • A New Large Capitosaurid Temnospondyl Amphibian from the Early Triassic of Poland
    A new large capitosaurid temnospondyl amphibian from the Early Triassic of Poland TOMASZ SULEJ and GRZEGORZ NIEDŹWIEDZKI Sulej, T. and Niedźwiedzki, G. 2013. A new large capitosaurid temnospondyl amphibian from the Early Triassic of Po− land. Acta Palaeontologica Polonica 58 (1): 65–75. The Early Triassic record of the large capitosaurid amphibian genus Parotosuchus is supplemented by new material from fluvial deposits of Wióry, southern Poland, corresponding in age to the Detfurth Formation (Spathian, Late Olenekian) of the Germanic Basin. The skull of the new capitosaurid shows an “intermediate” morphology between that of Paroto− suchus helgolandicus from the Volpriehausen−Detfurth Formation (Smithian, Early Olenekian) of Germany and the slightly younger Parotosuchus orenburgensis from European Russia. These three species may represent an evolutionary lineage that underwent a progressive shifting of the jaw articulation anteriorly. The morphology of the Polish form is dis− tinct enough from other species of Parotosuchus to warrant erection of a new species. The very large mandible of Parot− osuchus ptaszynskii sp. nov. indicates that this was one of the largest tetrapod of the Early Triassic. Its prominent anatomi− cal features include a triangular retroarticular process and an elongated base of the hamate process. Key words: Temnospondyli, Capitosauridae, Buntsandstein, Spathian, Olenekian, Triassic, Holy Cross Mountains, Poland. Tomasz Sulej [[email protected]], Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, PL−00−818 Warszawa, Poland; Grzegorz Niedźwiedzki [[email protected]], Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, PL−00−818 Warszawa, Poland; current addresses: Department of Organismal Biology, Uppsala Uni− versity, Norbyvägen 18A, 752 36 Uppsala, Sweden and Department of Paleobiology and Evolution, Faculty of Biology, University of Warsaw, ul.
    [Show full text]