DOCSLIB.ORG

Goniopholidid Crocodylomorph from the Middle Jurassic Berezovsk Quarry Locality (Western Siberia, Russia)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Goniopholidid Crocodylomorph from the Middle Jurassic Berezovsk Quarry Locality (Western Siberia, Russia) Proceedings of the Zoological Institute RAS Vol. 317, No. 4, 2013, рр. 452–458 УДК 57.072:551.762.2 GONIOPHOLIDID CROCODYLOMORPH FROM THE MIDDLE JURASSIC BEREZOVSK QUARRY LOCALITY (WESTERN SIBERIA, RUSSIA) I.T. Kuzmin1*, P.P. Skutschas1, O.I. Grigorieva1 and S.A. Krasnolutskii2 1Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 Saint Petersburg, Russia; e-mail: [email protected]; [email protected]; [email protected] 2Sharypovo Regional Museum, 2nd microrayon 10, Sharypovo, 662311 Krasnoyarsk Territory, Russia; e-mail: [email protected] ABSTRACT Excavations and sediment screenwashing at the Middle Jurassic Berezovsk Quarry locality in Krasnoyarsk Territory, Russia, yielded rare isolated teeth, osteoderms and fragments of cranial bones of crocodyliforms. All these remains were referred to Goniopholididae indet. on the basis of the following combination of features: a relatively narrow and long snout, contribution of splenials to the mandibular symphysis, dermal sculpturing consists of almost circular and slightly elongated oval pits, polygonal ventral osteoderms, and conical teeth with strongly striated crowns with weakly developed unserrated lateral carinae. The Berezovsk goniopholidid represents one of the oldest goniopholidid records in Asia and, geographically, the northernmost occurrence of this group in the Jurassic of Asia. Key words: Crocodyliformes, Goniopholididae, Itat Formation, Jurassic, Russia ГОНИОФОЛИДИДНЫЙ КРОКОДИЛОМОРФ ИЗ СРЕДНЕЮРСКОГО МЕСТОНАХОЖДЕНИЯ «БЕРЕЗОВСКИЙ РАЗРЕЗ» (ЗАПАДНАЯ СИБИРЬ, РОССИЯ) И.Т. Кузьмин1*, П.П. Скучас 1, О.И. Григорьева1 и С.А. Краснолуцкий2 1Санкт-Петербургский государственный университет, Университетская наб. 7/9, 199034 Санкт-Петербург, Россия; e-mail: [email protected]; [email protected]; [email protected] 2Шарыповский краеведческий музей, 2-й микрорайон 10, Шарыпово, 662311 Красноярский край, Россия; e-mail: [email protected] РЕЗЮМЕ Раскопки и промывка породы в среднеюрском местонахождении Березовский разрез в Красноярском Крае (Россия) позволила обнаружить редкие изолированные зубы, остеодермы и фрагменты черепных костей крокодилиформ. Все эти остатки были отнесены к Goniopholididae indet. на основании следующей комби- нации признаков: передняя часть морды сравнительно узкая и длинная, пластинчатые кости участвуют в формировании нижнечелюстного симфиза, скульптура покровных костей состоит из практически окру- глых или слабо удлиненных овальных ямок, вентральные остеодермы полигональной формы, зубы кони- ческие, с сильной струйчатостью и слабо развитыми незубчатыми латеральными гребнями. Гониофолидид из Березовского разреза один из древнейших представителей Goniopholididae в Азии и, географически, представляет собой наиболее северную находку этой группы в юре Азии. Kлючевые слова: Crocodyliformes, Goniopholididae, итатская свита, юра, Россия * Corresponding author / Автор-корреспондент. Goniopholidid from the Berezovsk Quarry locality 453 INTRODUCTION in the Berezovsk Quarry assemblage are fresh-water or terrestrial, indicating an in-land vertebrate com- The Middle Jurassic (Bathonian) microvertebrate munity (Averianov et al. 2005). Berezovsk Quarry locality (Western Siberia, Russia) has yielded remains of diverse fresh-water and ter- SYSTEMATICS restrial vertebrates (Alifanov et al. 2001; Averianov Crocodylomorpha Walker, 1970 et al. 2005, 2008, 2010a, b; Lopatin and Averianov Crocodyliformes Hay, 1930 2005, 2006, 2007, 2009; Skutschas et al. 2005; Ave- rianov and Lopatin 2006; Skutschas 2006; Averianov Mesoeucrocodylia Whetstone and Whybrow, 1983 and Krasnolutskii 2009). Crocodyliforms are among Neosuchia Benton and Clark, 1988 the rarest components of the Berezovsk Quarry ver- Goniopholididae Cope, 1875 tebrate assemblage and during more than ten years Goniopholididae indet. of regular excavations and intensive screenwashing (Figs. 1–3) several dozen of isolated teeth, osteoderms and very few fragments of cranial bones were found. The most Material. ZIN PH 1/176, maxillary fragment; diagnostic specimens are described in this paper. ZIN PH 2/176, fragment of left nasal; ZIN PH 3/176, Institutional abbreviations. ZIN PH, Paleoher- anterior fragment of right splenial; ZIN PH 4-8/176, petological collection, Zoological Institute of the Rus- teeth and 17 unnumbered teeth; ZIN PH 9/176, sian Academy of Sciences, Saint Petersburg, Russia. fragment of the dorsal osteoderm; ZIN PH 10/176, Locality. The Berezovsk Quarry locality is situ- fragmentary ventral osteoderm. ated 500 m south of Nikol’skoe village, Sharypovo Description. Maxilla. ZIN PH 1/176 is dorso- District, Krasnoyarsk Territory, Russia. Vertebrate ventrally flattened, small maxillary fragment with remains from the Berezovsk Quarry locality were broken palatal process (Fig. 1A–B). The fragment found in grey clays and sands in the upper part of is mediolaterally narrow, like in long-snouted croco- the Bathonian Itat Formation (for the detailed dyliform taxa. In ventral view, there are two distinct geological setting see Averianov et al. [2005]). The alveoli and a bifurcating groove along medial edge of Berezovsk Quarry vertebrate assemblage (besides the bone. This groove likely corresponds to a part of crocodyliforms) includes hybodont sharks (cf. Hybo- a passage for the maxillary branch of the trigeminal dus sp.), palaeonisciform (Palaeonisciformes indet.) nerve. The medial surface of the fragment is nearly and amiiform (Amiiformes indet.) actynopteryg- flat, straight in dorsal view and bears a facet for the ians, dipnoans (Dipnoi indet.), salamanders (Urupia nasal. The dorsal surface is sculptured by almost cir- monstrosa and two undescribed taxa) , xinjiangchelid cular and slightly anteroposteriorly elongated oval turtles (Xinjiangchelys sp.), primitive lepidosauro- pits. A neurovascular foramen is present dorsally to morphs (Lepidosauromorpha indet.), scincomorph the lateral margin of the fragment. lizards (Scincomorpha indet.), choristoderes (Cho- Nasal. ZIN PH 2/176 is a plate-like small frag- ristodera indet.), various ornithischian (Stego- ment of the left nasal (Fig. 1C–D). The fragment is sauria indet., Ornithischia indet.) and saurischian mediolaterally narrow and slightly tapers anteri- (Titanosauriformes indet., theropod Kileskus aris- orly. The ventral surface has two longitudinal grooves totocus) dinosaurs, pterosaurs (Pterosauria indet.), separated from each other in the posterior part of tritylodontids (Tritylodontidae indet.) and diverse the fragment by a relatively high ridge. The medial mammals (the eleutherodontid haramiyid Sineleu- groove is shallower and narrower than the lateral one. therus issedonicus, the docodonts Itatodon tatarinovi, These grooves correspond to the bony walls of the Simpsonodon sibiricus, and Hutegotherium yaomingi, nasal passages. The preserved part of facet for the left an amphilestid-grade eutriconodontan, the stem nasal on the medial surface is flat and straight in the therian Amphibetulimus krasnolutskii and an unde- dorsal view. The facet for maxilla on the lateral surface scribed dryolestid) (Alifanov et al. 2001; Averianov is slightly inclined. Sculpture of the dorsal surface is et al. 2005, 2008, 2010a, b, 2011; Lopatin and Averi- generally similar to that of maxilla, but differs in the anov 2005, 2006, 2007, 2009; Skutschas et al. 2005; presence of more anteroposteriorly elongated pits. Averianov and Lopatin 2006; Skutschas 2006, 2013; Splenial. ZIN PH 3/176 is the anteriormost frag- Averianov and Krasnolutskii 2009). All vertebrates ment of the right splenial with a partly preserved 454 I.T. Kuzmin et al. Fig. 1. Fragments of cranial bones of Goniopholididae indet. from Berezovsk Quarry, Krasnoyarsk Territory, Russia (Itat Formation, Middle Jurassic): A–B – ZIN PH 1/176, maxillary fragment, in dorsal (A) and ventral (B) views; C–D – ZIN PH 2/176, fragment of left nasal, in dorsal (C) and ventral (D) views; E–G – ZIN PH 3/176, anterior fragment of right splenial, in medial (E), lateral (F) and dorsal (G) views. Abbreviations: alv – alveoli; df – dentary facet; mf – maxillary facet; nf – nasal facet; sym – symphysis; V – groove for the trigeminal nerve;. Scale bar = 1 cm. Goniopholidid from the Berezovsk Quarry locality 455 Fig. 2. Isolated teeth of crocodyliform Goniopholididae indet. from Berezovsk Quarry, Krasnoyarsk Territory, Russia (Itat Formation, Middle Jurassic): A – ZIN PH 4/176, teeth of morphotype 1 in lateral view; B – ZIN PH 5/176, teeth of morphotype 1 in lateral view; C – ZIN PH 6/176, teeth of morphotype 1 in lateral view; D – ZIN PH 7/176, teeth of morphotype 2 in labial view; F – ZIN PH 8/176, teeth of morphotype 2 in lingual view. Scale bar = 3 mm. symphyseal region and a broken dorsal edge (Fig. pronounced and are more distinct closer to the tooth 1E–G). The fragment is robust and convex medially. apex than towards its base. The ventromedial surface is sculptured by shallow Among isolated teeth two distinctive morphotypes pits and relatively deep grooves. The ventral edge can be recognized. The first morphotype includes the is almost straight in lateral and medial views. Along most of specimens (n = 17) and represented by highly ventral edge, the lateral surface has a longitudinal conical teeth with rounded base and acute tip (Fig. facet for the dentary which is deep near the symphy- 2A–C). Teeth of this morphotype are slightly lin- sis and gradually tapering posteriorly. According to gually curved and circular or almost circular in cross the presence of the symphysis on the medial surface section (only the
Load more

Recommended publications
  • For Peer Review
    Biological Journal of the Linnean Society Marine tethysuchian c rocodyliform from the ?Aptian -Albian (Early Cretaceous) of the Isle of Wight, England Journal:For Biological Peer Journal of theReview Linnean Society Manuscript ID: BJLS-3227.R1 Manuscript Type: Research Article Date Submitted by the Author: 05-May-2014 Complete List of Authors: Young, Mark; University of Edinburgh, Biological Sciences; University of Southampton, School of Ocean and Earth Science Steel, Lorna; Natural History Museum, Earth Sciences Foffa, Davide; University of Bristol, Department of Earth Sciences Price, Trevor; Dinosaur Isle Museum, Naish, Darren; University of Southampton, School of Ocean and Earth Science Tennant, Jon; Imperial College London, Department of Earth Science and Engineering Albian, Aptian, Cretaceous, Dyrosauridae, England, Ferruginous Sands Keywords: Formation, Isle of Wight, Pholidosauridae, Tethysuchia, Upper Greensand Formation Biological Journal of the Linnean Society Page 1 of 50 Biological Journal of the Linnean Society 1 2 3 Marine tethysuchian crocodyliform from the ?Aptian-Albian (Early Cretaceous) 4 5 6 of the Isle of Wight, England 7 8 9 10 by MARK T. YOUNG 1,2 *, LORNA STEEL 3, DAVIDE FOFFA 4, TREVOR PRICE 5 11 12 2 6 13 DARREN NAISH and JONATHAN P. TENNANT 14 15 16 1 17 Institute of Evolutionary Biology, School of Biological Sciences, The King’s Buildings, University 18 For Peer Review 19 of Edinburgh, Edinburgh, EH9 3JW, United Kingdom 20 21 2 School of Ocean and Earth Science, National Oceanography Centre, University of Southampton,
    [Show full text]
  • 8. Archosaur Phylogeny and the Relationships of the Crocodylia
    8. Archosaur phylogeny and the relationships of the Crocodylia MICHAEL J. BENTON Department of Geology, The Queen's University of Belfast, Belfast, UK JAMES M. CLARK* Department of Anatomy, University of Chicago, Chicago, Illinois, USA Abstract The Archosauria include the living crocodilians and birds, as well as the fossil dinosaurs, pterosaurs, and basal 'thecodontians'. Cladograms of the basal archosaurs and of the crocodylomorphs are given in this paper. There are three primitive archosaur groups, the Proterosuchidae, the Erythrosuchidae, and the Proterochampsidae, which fall outside the crown-group (crocodilian line plus bird line), and these have been defined as plesions to a restricted Archosauria by Gauthier. The Early Triassic Euparkeria may also fall outside this crown-group, or it may lie on the bird line. The crown-group of archosaurs divides into the Ornithosuchia (the 'bird line': Orn- ithosuchidae, Lagosuchidae, Pterosauria, Dinosauria) and the Croco- dylotarsi nov. (the 'crocodilian line': Phytosauridae, Crocodylo- morpha, Stagonolepididae, Rauisuchidae, and Poposauridae). The latter three families may form a clade (Pseudosuchia s.str.), or the Poposauridae may pair off with Crocodylomorpha. The Crocodylomorpha includes all crocodilians, as well as crocodi- lian-like Triassic and Jurassic terrestrial forms. The Crocodyliformes include the traditional 'Protosuchia', 'Mesosuchia', and Eusuchia, and they are defined by a large number of synapomorphies, particularly of the braincase and occipital regions. The 'protosuchians' (mainly Early *Present address: Department of Zoology, Storer Hall, University of California, Davis, Cali- fornia, USA. The Phylogeny and Classification of the Tetrapods, Volume 1: Amphibians, Reptiles, Birds (ed. M.J. Benton), Systematics Association Special Volume 35A . pp. 295-338. Clarendon Press, Oxford, 1988.
    [Show full text]
  • Goniopholididae) from the Albian of Andorra (Teruel, Spain): Phylogenetic Implications
    Journal of Iberian Geology 41 (1) 2015: 41-56 http://dx.doi.org/10.5209/rev_JIGE.2015.v41.n1.48654 www.ucm.es /info/estratig/journal.htm ISSN (print): 1698-6180. ISSN (online): 1886-7995 New material from a huge specimen of Anteophthalmosuchus cf. escuchae (Goniopholididae) from the Albian of Andorra (Teruel, Spain): Phylogenetic implications E. Puértolas-Pascual1,2*, J.I. Canudo1,2, L.M. Sender2 1Grupo Aragosaurus-IUCA, Departamento de Ciencias de la Tierra, Facultad de Ciencias, Universidad de Zaragoza, c/Pedro Cerbuna 12, 50009 Zaragoza, Spain. 2Departamento de Ciencias de la Tierra, Facultad de Ciencias, Universidad de Zaragoza, c/Pedro Cerbuna No. 12, 50009 Zaragoza, Spain. e-mail addresses: [email protected] (E.P.P, *corresponding author); [email protected] (J.I.C.); [email protected] (L.M.S.) Received: 15 December 2013 / Accepted: 18 December 2014 / Available online: 25 March 2015 Abstract In 2011 the partial skeleton of a goniopholidid crocodylomorph was recovered in the ENDESA coal mine Mina Corta Barrabasa (Escu- cha Formation, lower Albian), located in the municipality of Andorra (Teruel, Spain). This new goniopholidid material is represented by abundant postcranial and fragmentary cranial bones. The study of these remains coincides with a recent description in 2013 of at least two new species of goniopholidids in the palaeontological site of Mina Santa María in Ariño (Teruel), also in the Escucha Formation. These species are Anteophthalmosuchus escuchae, Hulkepholis plotos and an undetermined goniopholidid, AR-1-3422. In the present paper, we describe the postcranial and cranial bones of the goniopholidid from Mina Corta Barrabasa and compare it with the species from Mina Santa María.
    [Show full text]
  • Alguns Crocodilianos São Mencionados Do Cretácico Português
    Paleo-herpetofauna de Portugal 69 Crocodlllanos Alguns Crocodilianos são mencionados do Cretácico português. No entanto, boa parte deste material carece de revisão e a sua classificação dos reajustamentos consequentes Do Cenomaniano Médio de Viso é referido um Mesosuchia/ Goniopholididae, Oweniasuchus lusitanicus Sauvage, 1897. Também do Maestrichtiano desta mesma localidade foram recolhidos numerosos frag­ mentos ósseos, identificados como pertencendo a Crocodylus blavieri Gray (Sauvage 1897/98 in Jonet 1981). No entanto Antunes & Pais (1978) colocaram algumas dúvidas a esta última identificação, referindo que so­ mente com base nos fragmentos encontrados, tanto poderia tratar-se de um mesossuquiano como de um eussuquiano. Restos de uma forma que consideraram semelhante à descrita, descoberta no Cretácico Superior de Taveiro, foi por eles identificada como sendo um Mesosuchia, n.gén., n.sp. (=Crocodylus blavieri Gray). Vestígios de exemplares desta forma, não designada, foram igualmente encontrados no Cacém. Do Cenomaniano Médio desta última localidade são também mencionados por Jonet (1981), os Mesosuchia/ Goniopholididae: Goniopholis cf. crassidens Owen, 1841 (pequeno crocodilo de cerca de 2 metros, também conhecido de Wealden - Cretácico Inferior - de Inglaterra e do Cretácico Inferior de Teruel), Oweniasuchus lusitanicus Sauvage, 1897, Oweniasuchus aff.lusitanicus, Oweniasuchus pulchelus Jonet, 1981 e, com dúvidas, o Eusuchia/ Crocodylidae, Thoracosaurus Leidy, 1852 sp .. Oweniasuchus pulchelus é também referido do Cenomaniano Superior de Carenque/Sintra (Jonet 1981) e Oweniasuchus sp., do Cenomaniano Médio de Forte Junqueiro/ Lisboa (Jonet 1981). 70 E. G. Crespo Restos indeterminados de Crocodilianos foram também encontrados no Cenomaniano Médio de Belas, Alto Pendão (Vale Figueira) e de Agualva/Cacém (todas localidades dos arredores de Lisboa) e do Cretácico Superior de Aveiro e das Azenhas do Mar (Sintra).
    [Show full text]
  • 71St Annual Meeting Society of Vertebrate Paleontology Paris Las Vegas Las Vegas, Nevada, USA November 2 – 5, 2011 SESSION CONCURRENT SESSION CONCURRENT
    ISSN 1937-2809 online Journal of Supplement to the November 2011 Vertebrate Paleontology Vertebrate Society of Vertebrate Paleontology Society of Vertebrate 71st Annual Meeting Paleontology Society of Vertebrate Las Vegas Paris Nevada, USA Las Vegas, November 2 – 5, 2011 Program and Abstracts Society of Vertebrate Paleontology 71st Annual Meeting Program and Abstracts COMMITTEE MEETING ROOM POSTER SESSION/ CONCURRENT CONCURRENT SESSION EXHIBITS SESSION COMMITTEE MEETING ROOMS AUCTION EVENT REGISTRATION, CONCURRENT MERCHANDISE SESSION LOUNGE, EDUCATION & OUTREACH SPEAKER READY COMMITTEE MEETING POSTER SESSION ROOM ROOM SOCIETY OF VERTEBRATE PALEONTOLOGY ABSTRACTS OF PAPERS SEVENTY-FIRST ANNUAL MEETING PARIS LAS VEGAS HOTEL LAS VEGAS, NV, USA NOVEMBER 2–5, 2011 HOST COMMITTEE Stephen Rowland, Co-Chair; Aubrey Bonde, Co-Chair; Joshua Bonde; David Elliott; Lee Hall; Jerry Harris; Andrew Milner; Eric Roberts EXECUTIVE COMMITTEE Philip Currie, President; Blaire Van Valkenburgh, Past President; Catherine Forster, Vice President; Christopher Bell, Secretary; Ted Vlamis, Treasurer; Julia Clarke, Member at Large; Kristina Curry Rogers, Member at Large; Lars Werdelin, Member at Large SYMPOSIUM CONVENORS Roger B.J. Benson, Richard J. Butler, Nadia B. Fröbisch, Hans C.E. Larsson, Mark A. Loewen, Philip D. Mannion, Jim I. Mead, Eric M. Roberts, Scott D. Sampson, Eric D. Scott, Kathleen Springer PROGRAM COMMITTEE Jonathan Bloch, Co-Chair; Anjali Goswami, Co-Chair; Jason Anderson; Paul Barrett; Brian Beatty; Kerin Claeson; Kristina Curry Rogers; Ted Daeschler; David Evans; David Fox; Nadia B. Fröbisch; Christian Kammerer; Johannes Müller; Emily Rayfield; William Sanders; Bruce Shockey; Mary Silcox; Michelle Stocker; Rebecca Terry November 2011—PROGRAM AND ABSTRACTS 1 Members and Friends of the Society of Vertebrate Paleontology, The Host Committee cordially welcomes you to the 71st Annual Meeting of the Society of Vertebrate Paleontology in Las Vegas.
    [Show full text]
  • Microvertebrates of the Lourinhã Formation (Late Jurassic, Portugal)
    Alexandre Renaud Daniel Guillaume Licenciatura em Biologia celular Mestrado em Sistemática, Evolução, e Paleobiodiversidade Microvertebrates of the Lourinhã Formation (Late Jurassic, Portugal) Dissertação para obtenção do Grau de Mestre em Paleontologia Orientador: Miguel Moreno-Azanza, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa Co-orientador: Octávio Mateus, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa Júri: Presidente: Prof. Doutor Paulo Alexandre Rodrigues Roque Legoinha (FCT-UNL) Arguente: Doutor Hughes-Alexandres Blain (IPHES) Vogal: Doutor Miguel Moreno-Azanza (FCT-UNL) Júri: Dezembro 2018 MICROVERTEBRATES OF THE LOURINHÃ FORMATION (LATE JURASSIC, PORTUGAL) © Alexandre Renaud Daniel Guillaume, FCT/UNL e UNL A Faculdade de Ciências e Tecnologia e a Universidade Nova de Lisboa tem o direito, perpétuo e sem limites geográficos, de arquivar e publicar esta dissertação através de exemplares impressos reproduzidos em papel ou de forma digital, ou por qualquer outro meio conhecido ou que venha a ser inventado, e de a divulgar através de repositórios científicos e de admitir a sua cópia e distribuição com objetivos educacionais ou de investigação, não comerciais, desde que seja dado crédito ao autor e editor. ACKNOWLEDGMENTS First of all, I would like to dedicate this thesis to my late grandfather “Papi Joël”, who wanted to tie me to a tree when I first start my journey to paleontology six years ago, in Paris. And yet, he never failed to support me at any cost, even if he did not always understand what I was doing and why I was doing it. He is always in my mind. Merci papi ! This master thesis has been one-year long project during which one there were highs and lows.
    [Show full text]
  • New Transitional Fossil from Late Jurassic of Chile Sheds Light on the Origin of Modern Crocodiles Fernando E
    www.nature.com/scientificreports OPEN New transitional fossil from late Jurassic of Chile sheds light on the origin of modern crocodiles Fernando E. Novas1,2, Federico L. Agnolin1,2,3*, Gabriel L. Lio1, Sebastián Rozadilla1,2, Manuel Suárez4, Rita de la Cruz5, Ismar de Souza Carvalho6,8, David Rubilar‑Rogers7 & Marcelo P. Isasi1,2 We describe the basal mesoeucrocodylian Burkesuchus mallingrandensis nov. gen. et sp., from the Upper Jurassic (Tithonian) Toqui Formation of southern Chile. The new taxon constitutes one of the few records of non‑pelagic Jurassic crocodyliforms for the entire South American continent. Burkesuchus was found on the same levels that yielded titanosauriform and diplodocoid sauropods and the herbivore theropod Chilesaurus diegosuarezi, thus expanding the taxonomic composition of currently poorly known Jurassic reptilian faunas from Patagonia. Burkesuchus was a small‑sized crocodyliform (estimated length 70 cm), with a cranium that is dorsoventrally depressed and transversely wide posteriorly and distinguished by a posteroventrally fexed wing‑like squamosal. A well‑defned longitudinal groove runs along the lateral edge of the postorbital and squamosal, indicative of a anteroposteriorly extensive upper earlid. Phylogenetic analysis supports Burkesuchus as a basal member of Mesoeucrocodylia. This new discovery expands the meagre record of non‑pelagic representatives of this clade for the Jurassic Period, and together with Batrachomimus, from Upper Jurassic beds of Brazil, supports the idea that South America represented a cradle for the evolution of derived crocodyliforms during the Late Jurassic. In contrast to the Cretaceous Period and Cenozoic Era, crocodyliforms from the Jurassic Period are predomi- nantly known from marine forms (e.g., thalattosuchians)1.
    [Show full text]
  • Big-Headed Marine Crocodyliforms and Why We Must Be Cautious When Using Extant Species As Body Length Proxies for Long-Extinct Relatives
    Palaeontologia Electronica palaeo-electronica.org Big-headed marine crocodyliforms and why we must be cautious when using extant species as body length proxies for long-extinct relatives Mark T. Young, Márton Rabi, Mark A. Bell, Davide Foffa, Lorna Steel, Sven Sachs, and Karin Peyer ABSTRACT Body size is commonly used as a key variable for estimating ecomorphological trends at a macroevolutionary scale, making reliable body length estimates of fossil taxa critically important. Crocodylomorphs (extant crocodylians and their extinct rela- tives) evolved numerous 'aberrant' body-plans during their ~230 million-year history, ranging from ‘hooved’ terrestrial species to dolphin-like pelagic species. Such clades evolved distinct cranial and femoral scaling ratios (compared to total body length), thereby making extant taxa unsuitable proxies for estimating their body lengths. Here we illustrate that the fossil clade Teleosauridae also fits into this category. Teleosaurids were a predominately shallow marine clade that had a global distribution during the Jurassic. Known to have evolved a wide range of body lengths (2–5 m based on com- plete skeletons), there is currently no way of reliably estimating the size of incomplete specimens. This is surprising, as some teleosaurids have been considered very large (9–10 m in total length), thus making Teleosauridae the largest bodied clade during the first 100 million years of crocodylomorph evolution. Our examination and regression analyses of the best preserved teleosaurid skeletons demonstrates that: they were smaller than previously thought, with no known specimen exceeding 7.2 m in length; and that they had proportionally large skulls, and proportionally short femora, when compared to body length.
    [Show full text]
  • Aspects of the Microvertebrate Fauna of the Early Cretaceous (Barremian) Wessex Formation of the Isle of Wight, Southern England
    ASPECTS OF THE MICROVERTEBRATE FAUNA OF THE EARLY CRETACEOUS (BARREMIAN) WESSEX FORMATION OF THE ISLE OF WIGHT, SOUTHERN ENGLAND By STEVEN CHARLES SWEETMAN M.A. (Oxon.) 1980 F.G.S. A thesis submitted in partial fulfilment of the requirements for the award of the degree of Doctor of Philosophy of the University of Portsmouth School of Earth and Environmental Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth, PO1 3QL, U.K. April, 2007 0 Disclaimer Whilst registered for this degree, I have not registered for any other award. No part of this work has been submitted for any other academic award. 1 Acknowledgements At inception of this project there was a significant risk that the Wessex Formation would not yield a microvertebrate fauna. I would, therefore, like to express special thanks to Dave Martill (University of Portsmouth) for his initial support and for securing the research scholarship which made this study possible. I would also like to thank him for his supervision, generous support, encouragement and advice thereafter. Special thanks also to Susan Evans (UCL) for her enthusiastic help and advice on all matters relating to microvertebrates in general, and lizards in particular, and to Jerry Hooker (NHM) for everything relating to mammals; also to Brian Gasson for his support in the field and for the generous donation of many exceptional specimens from his private collection. The broad scope of this study has engendered the help, support and advice of many others and I am grateful to all. At the University
    [Show full text]
  • Palaeobiodiversity of Crocodylomorphs from the Lourinhã Formation Based on the Tooth Record: Insights Into the Palaeoecology of the Late Jurassic of Portugal
    applyparastyle “fig//caption/p[1]” parastyle “FigCapt” Zoological Journal of the Linnean Society, 2019, XX, 1–35. With 17 figures. Downloaded from https://academic.oup.com/zoolinnean/advance-article-abstract/doi/10.1093/zoolinnean/zlz112/5648910 by Boston University user on 02 December 2019 Palaeobiodiversity of crocodylomorphs from the Lourinhã Formation based on the tooth record: insights into the palaeoecology of the Late Jurassic of Portugal ALEXANDRE R. D. GUILLAUME1,2,*, , MIGUEL MORENO-AZANZA1,2, EDUARDO PUÉRTOLAS-PASCUAL1,2, and OCTÁVIO MATEUS1,2, 1GeoBioTec, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Caparica, Portugal 2Museu da Lourinhã, Lourinhã. Portugal Received 7 March 2019; revised 19 August 2019; accepted for publication 28 August 2019 Crocodylomorphs were a diverse clade in the Late Jurassic of Portugal, with six taxa reported to date. Here we describe 126 isolated teeth recovered by screen-washing of sediments from Valmitão (Lourinhã, Portugal, late Kimmeridgian–Tithonian), a vertebrate microfossil assemblage in which at least five distinct crocodylomorph taxa are represented. Ten morphotypes are described and attributed to five clades (Lusitanisuchus, Atoposauridae, Goniopholididae, Bernissartiidae and an undetermined mesoeucrocodylian). Four different ecomorphotypes are here proposed according to ecological niches and feeding behaviours: these correspond to a diet based on arthropods and small vertebrates (Lusitanisuchus and Atoposauridae), a generalist diet (Goniopholididae), a durophagous diet (Bernissartiidae) and a carnivorous diet. Lusitanisuchus mitracostatus material from Guimarota is here redescribed to achieve a better illustration and comparison with the new material. This assemblage shares similar ecomorphotypes with other Mesozoic west-central European localities, where a diversity of crocodylomorphs lived together, avoiding direct ecological competition through niche partitioning.
    [Show full text]
  • A New Docodont (Mammalia) from the Middle Jurassic of Kyrgyzstan, Central Asia
    Journal of Vertebrate Paleontology 24(1):195±201, March 2004 q 2004 by the Society of Vertebrate Paleontology A NEW DOCODONT (MAMMALIA) FROM THE MIDDLE JURASSIC OF KYRGYZSTAN, CENTRAL ASIA THOMAS MARTIN1 and ALEXANDER O. AVERIANOV2 1Institut fuÈr Geologische Wissenschaften, Fachrichtung PalaÈontologie, Freie UniversitaÈt, Malterserstrasse 74-100, D-12249 Berlin, Germany, [email protected]; 2Zoological Institute, Russian Academy of Sciences, Universitetskaya nab. 1, St. Petersburg 199034, Russia, [email protected] ABSTRACTÐTashkumyrodon desideratus, gen. et sp. nov. from the Middle Jurassic (Callovian) Balabansai Formation near Tashkumyr in Kyrgyzstan is described from a single lower molar. The tooth exhibits the typical structure of a docodont lower molar with the main cusp a connected by crests to the lingual cusps (c and g) and to the mesial cusp b. Tashkumyrodon is plesiomorphic in retaining well developed crests c-d and d-f, and derived in reduction of crest b-g. By formation of crests b-e and e-g (derived), Tashkumyrodon resembles Tegotherium from the Late Jurassic of Mongolia and Sibirotherium from the Early Cretaceous of West Siberia, Russia. Tegotherium is more derived than Tashkumyrodon by the more prominent anterior basin (``pseudotalonid'') and the reduction of the crests distal to cusp c. The Asian docodonts probably represent the sister group of all remaining docodonts, an Euramerican clade char- acterized by retention of crest b-g and reduction of cusp e as well as crest b-e. Simpsonodon from the Middle Jurassic of England is convergently similar to Tegotherium in development of a ``pseudotalonid'' and reduction of distal crests. INTRODUCTION began ®eld work in Kyrgyzstan with the aim to recover Jurassic mammals.
    [Show full text]
  • REVIEW of the CONTINENTAL MESOZOIC STRATIGRAPHY of THAILAND Nares Sattayarak Mineral Fuels Division Department of Mineral Resources Bangkok 10400, Thailand
    WORKSHOP ON STRATIGRAPHIC CORRELATION OF THAILAND AND MALAYSIA Haad Yai, Thailand 8-10 Septdber, 1983 REVIEW OF THE CONTINENTAL MESOZOIC STRATIGRAPHY OF THAILAND Nares Sattayarak Mineral Fuels Division Department of Mineral Resources Bangkok 10400, Thailand IRTRODUCTIOH The continental Mesozoic redbeds are widely distributed throughout the country, especially in the Khorat Plateau, from which the group's name was obtained. The rocks are predominantly red clastic, i.e. , sandstone, silt­ stone, claystone, shale and conglomerate. The Khorat Group rests. uncon­ formably on older rocks, generally of Paleozoic age, but occasionally it overlies the Permo-Triassic igneous rocks and/or Lower to Middle Triassic sedimentary rocks. The Khorat Group was previously reviewed in Thai by Nakornsri (1975) and in English by Kulasing ( 1975) and Ramingwong ( 1978) • This paper is an attempt to update the knowledge so far reported about the Khorat rocks and their equivalents. REVIEW OF PREVIOUS WORKS Lee (1923) was the first geologist who noted the non-marine Mesozoic rocks in the Khorat Plateau and divided them into Upper and Lower Group, the Triassic age was given. Brown et al. ( 1953) named the IChorat Series to represent the conti­ nental redbeds and the marine Triassic limestone of northern Thailand. The sequence consists of interbedded sandstone, conglomerate, shale and marly limestone. No fossil was found except some petrified wood. La Moreaux et al. (1956) divided the Khorat Series, following Chali­ chan and Bunnag ( 1954) , into three members and assigned the age of this sequence to the Triassic period. Their subdivision are as follows: Phu Kradung Member is the oldest member it lies unconformably on Paleozoic rocks.
    [Show full text]