T H E Volumes of the University of Michigan Studies Are Published By
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Crocodylomorpha, Neosuchia), and a Discussion on the Genus Theriosuchus
bs_bs_banner Zoological Journal of the Linnean Society, 2015. With 5 figures The first definitive Middle Jurassic atoposaurid (Crocodylomorpha, Neosuchia), and a discussion on the genus Theriosuchus MARK T. YOUNG1,2, JONATHAN P. TENNANT3*, STEPHEN L. BRUSATTE1,4, THOMAS J. CHALLANDS1, NICHOLAS C. FRASER1,4, NEIL D. L. CLARK5 and DUGALD A. ROSS6 1School of GeoSciences, Grant Institute, The King’s Buildings, University of Edinburgh, James Hutton Road, Edinburgh EH9 3FE, UK 2School of Ocean and Earth Science, National Oceanography Centre, University of Southampton, European Way, Southampton SO14 3ZH, UK 3Department of Earth Science and Engineering, Imperial College London, London SW6 2AZ, UK 4National Museums Scotland, Chambers Street, Edinburgh EH1 1JF, UK 5The Hunterian, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK 6Staffin Museum, 6 Ellishadder, Staffin, Isle of Skye IV51 9JE, UK Received 1 December 2014; revised 23 June 2015; accepted for publication 24 June 2015 Atoposaurids were a clade of semiaquatic crocodyliforms known from the Late Jurassic to the latest Cretaceous. Tentative remains from Europe, Morocco, and Madagascar may extend their range into the Middle Jurassic. Here we report the first unambiguous Middle Jurassic (late Bajocian–Bathonian) atoposaurid: an anterior dentary from the Isle of Skye, Scotland, UK. A comprehensive review of atoposaurid specimens demonstrates that this dentary can be referred to Theriosuchus based on several derived characters, and differs from the five previously recog- nized species within this genus. Despite several diagnostic features, we conservatively refer it to Theriosuchus sp., pending the discovery of more complete material. As the oldest known definitively diagnostic atoposaurid, this discovery indicates that the oldest members of this group were small-bodied, had heterodont dentition, and were most likely widespread components of European faunas. -
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. -
Ministerio De Cultura Y Educacion Fundacion Miguel Lillo
MINISTERIO DE CULTURA Y EDUCACION FUNDACION MIGUEL LILLO NEW MATERIALS OF LAGOSUCHUS TALAMPAYENSIS ROMER (THECODONTIA - PSEUDOSUCHIA) AND ITS SIGNIFICANCE ON THE ORIGIN J. F. BONAPARTE OF THE SAURISCHIA. LOWER CHANARIAN, MIDDLE TRIASSIC OF ARGENTINA ACTA GEOLOGICA LILLOANA 13, 1: 5-90, 10 figs., 4 pl. TUCUMÁN REPUBLICA ARGENTINA 1975 NEW MATERIALS OF LAGOSUCHUS TALAMPAYENSIS ROMER (THECODONTIA - PSEUDOSUCHIA) AND ITS SIGNIFICANCE ON THE ORIGIN OF THE SAURISCHIA LOWER CHANARIAN, MIDDLE TRIASSIC OF ARGENTINA* by JOSÉ F. BONAPARTE Fundación Miguel Lillo - Career Investigator Member of CONICET ABSTRACT On the basis of new remains of Lagosuchus that are thoroughly described, including most of the skeleton except the manus, it is assumed that Lagosuchus is a form intermediate between Pseudosuchia and Saurischia. The presacral vertebrae show three morphological zones that may be related to bipedality: 1) the anterior cervicals; 2) short cervico-dorsals; and 3) the posterior dorsals. The pelvis as a whole is advanced, in particular the pubis and acetabular area of the ischium, but the ilium is rather primitive. The hind limb has a longer tibia than femur, and the symmetrical foot is as long as the tibia. The tarsus is of the mesotarsal type. The morphology of the distal area of the tibia and fibula, and the proximal area of the tarsus, suggest a stage transitional between the crurotarsal and mesotarsal conditions. The forelimb is proportionally short, 48% of the hind limb. The humerus is slender, with advanced features in the position of the deltoid crest. The radius and ulna are also slender, the latter with a pronounced olecranon process. A new family of Pseudosuchia is proposed for this form: Lagosuchidae. -
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. -
CROCODYLIFORMES, MESOEUCROCODYLIA) from the EARLY CRETACEOUS of NORTH-EAST BRAZIL by DANIEL C
[Palaeontology, Vol. 52, Part 5, 2009, pp. 991–1007] A NEW NEOSUCHIAN CROCODYLOMORPH (CROCODYLIFORMES, MESOEUCROCODYLIA) FROM THE EARLY CRETACEOUS OF NORTH-EAST BRAZIL by DANIEL C. FORTIER and CESAR L. SCHULTZ Departamento de Paleontologia e Estratigrafia, UFRGS, Avenida Bento Gonc¸alves 9500, 91501-970 Porto Alegre, C.P. 15001 RS, Brazil; e-mails: [email protected]; [email protected] Typescript received 27 March 2008; accepted in revised form 3 November 2008 Abstract: A new neosuchian crocodylomorph, Susisuchus we recovered the family name Susisuchidae, but with a new jaguaribensis sp. nov., is described based on fragmentary but definition, being node-based group including the last com- diagnostic material. It was found in fluvial-braided sedi- mon ancestor of Susisuchus anatoceps and Susisuchus jagua- ments of the Lima Campos Basin, north-eastern Brazil, ribensis and all of its descendents. This new species 115 km from where Susisuchus anatoceps was found, in corroborates the idea that the origin of eusuchians was a rocks of the Crato Formation, Araripe Basin. S. jaguaribensis complex evolutionary event and that the fossil record is still and S. anatoceps share a squamosal–parietal contact in the very incomplete. posterior wall of the supratemporal fenestra. A phylogenetic analysis places the genus Susisuchus as the sister group to Key words: Crocodyliformes, Mesoeucrocodylia, Neosuchia, Eusuchia, confirming earlier studies. Because of its position, Susisuchus, new species, Early Cretaceous, north-east Brazil. B razilian crocodylomorphs form a very expressive Turonian–Maastrichtian of Bauru basin: Adamantinasu- record of Mesozoic vertebrates, with more than twenty chus navae (Nobre and Carvalho, 2006), Baurusuchus species described up to now. -
A New Longirostrine Dyrosaurid
[Palaeontology, Vol. 54, Part 5, 2011, pp. 1095–1116] A NEW LONGIROSTRINE DYROSAURID (CROCODYLOMORPHA, MESOEUCROCODYLIA) FROM THE PALEOCENE OF NORTH-EASTERN COLOMBIA: BIOGEOGRAPHIC AND BEHAVIOURAL IMPLICATIONS FOR NEW-WORLD DYROSAURIDAE by ALEXANDER K. HASTINGS1, JONATHAN I. BLOCH1 and CARLOS A. JARAMILLO2 1Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA; e-mails: akh@ufl.edu, jbloch@flmnh.ufl.edu 2Smithsonian Tropical Research Institute, Box 0843-03092 and #8232, Balboa-Ancon, Panama; e-mail: [email protected] Typescript received 19 March 2010; accepted in revised form 21 December 2010 Abstract: Fossils of dyrosaurid crocodyliforms are limited rosaurids. Results from a cladistic analysis of Dyrosauridae, in South America, with only three previously diagnosed taxa using 82 primarily cranial and mandibular characters, sup- including the short-snouted Cerrejonisuchus improcerus from port an unresolved relationship between A. guajiraensis and a the Paleocene Cerrejo´n Formation of north-eastern Colom- combination of New- and Old-World dyrosaurids including bia. Here we describe a second dyrosaurid from the Cerrejo´n Hyposaurus rogersii, Congosaurus bequaerti, Atlantosuchus Formation, Acherontisuchus guajiraensis gen. et sp. nov., coupatezi, Guarinisuchus munizi, Rhabdognathus keiniensis based on three partial mandibles, maxillary fragments, teeth, and Rhabdognathus aslerensis. Our results are consistent with and referred postcrania. The mandible has a reduced seventh an African origin for Dyrosauridae with multiple dispersals alveolus and laterally depressed retroarticular process, both into the New World during the Late Cretaceous and a transi- diagnostic characteristics of Dyrosauridae. Acherontisuchus tion from marine habitats in ancestral taxa to more fluvial guajiraensis is distinct among known dyrosaurids in having a habitats in more derived taxa. -
First Post-Mesozoic Record of Crocodyliformes from Chile
First post−Mesozoic record of Crocodyliformes from Chile STIG A. WALSH and MARIO SUÁREZ Walsh, S.A. and Suárez, M. 2005. First post−Mesozoic record of Crocodyliformes from Chile. Acta Palaeontologica Polonica 50 (3): 595–600. Fossil crocodilians are well known from vertebrate bearing localities in South America, but the last record of the group in Chile is from the Cretaceous. No living crocodilians occur in Chile today, and the timing of their disappearance from the country is unknown. We provide the first post−Mesozoic report of crocodilian remains from late Miocene marine deposits of the Bahía Inglesa Formation, northern Chile. The fragmentary material provides proof that Crocodiliformes were pres− ent in Chile until at least seven million years ago. We suggest that late Neogene climatic cooling and changes in South American palaeophysiography caused the extinction of the group in Chile. Key words: Crocodyliformes, climate change, extinction, Bahía Inglesa Formation, Neogene, Chile. Stig A. Walsh [[email protected]], Department of Palaeontology, Natural History Museum, Cromwell Road, London, United Kingdom; Mario E. Suárez [[email protected]], Museo Paleontológico de Caldera, Av. Wheelright, Caldera, Chile. Introduction Inglesa Formation of northern Chile. The occurrence of these specimens in late Miocene sediments demonstrates that cro− Crocodilians have a long and diverse fossil record in South codilians were present in Chile until at least seven million America, with Tertiary freshwater and terrestrial deposits in years ago. particular having provided exceptionally rich faunas. In fact, Institutional abbreviations.—BMNH, Natural History Mu− crocodilians are encountered throughout much of the South seum, London, United Kingdom; MNHN, Muséum National American Tertiary, and are known from Argentina, Brazil, d’Histoire Naturelle, Paris, France; SGO−PV, Sección Pale− Colombia, Peru, and Venezuela (Langstone 1965; Buffetaut ontología, Museo Nacional de Historia Natural, Santiago, 1982; Gasparini 1996; Brochu 1999; Kay et al. -
Evidence for Endothermic Ancestors of Crocodiles at the Stem of Archosaur Evolution Author(S): Roger S
Division of Comparative Physiology and Biochemistry, Society for Integrative and Comparative Biology Evidence for Endothermic Ancestors of Crocodiles at the Stem of Archosaur Evolution Author(s): Roger S. Seymour, Christina L. Bennett‐Stamper, Sonya D. Johnston, David R. Carrier, and Gordon C. Grigg Source: Physiological and Biochemical Zoology, Vol. 77, No. 6, Sixth International Congress of Comparative Physiology and Biochemistry Symposium Papers: Evolution and Advantages of Endothermy (November/December 2004), pp. 1051-1067 Published by: The University of Chicago Press. Sponsored by the Division of Comparative Physiology and Biochemistry, Society for Integrative and Comparative Biology Stable URL: http://www.jstor.org/stable/10.1086/422766 . Accessed: 04/11/2015 23:31 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. The University of Chicago Press and Division of Comparative Physiology and Biochemistry, Society for Integrative and Comparative Biology are collaborating with JSTOR to digitize, preserve and extend access to Physiological and Biochemical Zoology. http://www.jstor.org This content downloaded from 23.235.32.0 on Wed, 4 Nov 2015 23:31:05 PM All use subject to JSTOR Terms and Conditions 1051 Evidence for Endothermic Ancestors of Crocodiles at the Stem of Archosaur Evolution Roger S. -
CROCODYLIDAE Crocodylus Rhombifer
n REPTILIA: CROCODILIA: CROCODYLIDAE Catalogue of American Amphibians and Reptiles. Crocidilrts rhornbifer: Velasco 1893:80. Spelling error. Crocodrilus rhombifer: Velasco 1895:37. Spelling error. Ross, F.D. 1998. Crocodylus rliombifer. Crocodiltrs rliombifenrs: Reese 1915:2. Spelling error. Crocodylus rhombifer: Stejneger 19 17:289. First use of present Crocodylus rhombifer (Cuvier) combination. Cuban Crocodile Crocodylus antillensis Varona 1966:27, figs. 9-1 I. Type local- ity, Pleistocene deposits at Cueva Lamas, near Santa Fe, La Crocodilrrs rhombifer Cuvier 1807:s 1. Distribution of the spe- Habana Province, Cuba. Holotype (posterior skull fragment), cies was first associated with Cuba by DumCril and Bibron Institute Biologia Cuba, IB I0 I, collected by Oscar Arredondo (1836), who also described the species from life in diagnos- (OA 368). Paratypes include maxillary, premaxillary, and tic detail. The type locality was restricted to Cuba by Schmidt squamosal bones. Synonymy is by Varona (1966). (1924). Two known syntypes, one at I'AcadCmie des Sci- Crocodylus rhontbifera: Das 1994:200. Spelling error. ences, Paris, and the other in the MusCum National de'Histoire Naturelle, Paris (MNHNP),are both currently unlocated (see CONTENT. Crocodylus rhombifpr is a monotypic species Remarks). No lectotype has been designated. including Pleistocene fossils. Wild hybrids are suspected. For croc rhombifer: Cuvier 18 17:2 1 (in a footnote). a discussion of captive hybridization between C. rhombifer and Crocodilus @laniro.stris)Graves 18 19:348. Type locality: "Af- several other species of Crocod.ylus, see Comments. rica" (in error). The type specimen, in the Museum of Bor- deaux, was formerly in the private collection of the Count of DEFINITION and DIAGNOSIS. -
Cretaceous), Brazil
Gondwana Research, V. 8, No. 1, pp. 11-30. © 2005 International Association for Gondwana Research, Japan.ISSN: 1342-937X Gondwana Research Baurusuchus salgadoensis, a New Crocodylomorpha from the Bauru Basin (Cretaceous), Brazil Ismar de Souza Carvalho1, Antonio de Celso Arruda Campos2 and Pedro Henrique Nobre1 1 Universidade Federal do Rio de Janeiro. Departamento de Geologia, CCMN/IGEO. 21.949-900 Cidade Universitária - Ilha do Fundão. Rio de Janeiro - RJ, Brazil, E-mail: [email protected] 2 Museu de Paleontologia de Monte Alto. Praça do Centenário, Centro de Artes s/nº. 15.910-000 Monte Alto – SP, Brazil, E-mail: [email protected] (Manuscript received October 3, 2003; accepted June 20, 2004) Abstract Baurusuchus salgadoensis is a new baurusuchid crocodylomorph from Bauru Basin (Cretaceous), Brazil, partially preserved through a complete skull. The fossil comes from a fine sandstone sequence of Adamantina Formation, General Salgado County, São Paulo State. The sedimentary sequence where it was found, located in Fazenda Buriti, is considered Turonian-Santonian in age. The described species – Baurusuchus salgadoensis sp. nov. – is a baurusuchid with an antorbital fenestra, double external nares with a bony septum, two well-fused supraorbitals, the supratemporal fenestrae larger than the orbits and a quadrangular-shaped laterotemporal fenestra. The position of the external nares, located on anterior and terminal portion of the rostrum together with the theropod-like lateral compression of the snout and teeth are indicators that Baurusuchus salgadoensis was a terrestrial crocodyliform. This was a carnivorous species and the lateral compression of the rostrum could be interpreted as a mechanism to increase the skull resistance forces during biting. -
Crocodilia, Thalattosuchia) from the Kimmeridgian of Germany
Fossil Record 16 (1) 2013, 179–196 / DOI 10.1002/mmng.201300009 New remains of Machimosaurus hugii von Meyer, 1837 (Crocodilia, Thalattosuchia) from the Kimmeridgian of Germany Jeremy E. Martin*,1and Peggy Vincent2 1 School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol, BS8 1RJ, United Kingdom. E-mail: [email protected] 2 Staatliches Museum fr Naturkunde, Rosenstein 1, 70191 Stuttgart, Germany. E-mail: [email protected] Abstract Received 16 August 2012 The fourth complete skull of the marine crocodilian Machimosaurus von Meyer, 1837 Accepted 12 March 2013 is hereby described together with an associated complete mandible and disarticulated Published 5 August 2013 postcranial elements from the Kimmeridgian of Neuffen, Germany. Although the genus has been described fairly recently on the basis of two nearly complete skulls, their state of preservation did not allow a thorough examination of the entire skull anatomy. Here, we add new information with the description of nicely preserved cranial and mandibu- lar elements of a single individual attributable to Machimosaurus hugii von Meyer, 1837. The diagnosis is updated for the genus and for the species M. hugii and chal- Key Words lenges the validity of the second species M. mosae (Linard, 1876). Moreover, previous assumption that Steneosaurus obtusidens Andrews, 1913 is a junior synonym of Machi- Crocodilia mosaurus hugii is not supported by our observations. Notably, M. hugii differs from Germany S. obtusidens by a lower tooth count, the morphology of the dentition, the shape of the Kimmeridgian supratemporal fenestrae and the absence of an antorbital fenestra. -
Part-0095251E.Pdf
CROCODILES Proceedings of the 21st Working Meeting of the Crocodile Specialist Group of the Species Survival Commission of the IUCN convened at Manila, Philippines, 22-25 May 2012 Dedicated to the late Charles “Andy” Ross (1953-2011) (Unreviewed) International Union for Conservation of Nature (IUCN) Rue Mauverney 28, CH-1196, Gland, Switzerland 2012 1 Front cover: Philippine Crocodile, Crocodylus mindorensis. © Crocodylus Porosus Philippines Inc. Inner front cover: Charles “Andy” Ross. © Tom Dacey Literature citations should read as follows: For individual articles: [Authors]. (2012). [Article title]. Pp. [page numbers] in Crocodiles. Proceedings of the 21st Working Meeting of the IUCN-SSC Crocodile Specialist Group. IUCN: Gland, Switzerland. For the volume: Crocodile Specialist Group (2012). Crocodiles. Proceedings of the 21st Working Meeting of the IUCN- SSC Crocodile Specialist Group. IUCN: Gland, Switzerland. © 2012 CSG - Crocodile Specialist Group The designation of geographical entities in this book and the presentation of the material do not imply the expression of any opinion whatsoever on the part of the IUCN concerning the legal status of any country, territory, or area, or its authorities, or concerning the delimitation of its frontiers or boundaries. The opinions expressed in this colume are those of the authors and do not necessarily represent official policy of the IUCN or CSG or its members. Reproduction of this publication for educational and other non-commercial purposes is authorized from the copyright holder, provided the source is cited and the copyright holder receives copy of the reproduced material. Reproduction for resale or other commercial purposes is prohibited without prior permission of the copyright holder.