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Page 12 of 19, showing 20 record(s) out of 368 total

On the genus Dikkomys (Geomyoidea, Mammalia)
Morton Green and Philip R. Bjork
Published online: 01/10/1980

Keywords: Dikkomys; Geomyoidae; North America

https://doi.org/10.18563/pv.9.ext.343-353

  Abstract

    The geomyoid genus Dikkomys is well represented in a sample from the Black Bear Quarry Il local fauna of Early Hemingfordian age in Bennett County, South Dakota. Isolated unworn P/4's of Dikkomys matthewi WOOD have a prominent median cristid (sagicristid) with a connection to the metaconid and the hypolophid. With wear, P/4 does not become as molariform as P/4 because of this cristid.
    A large sample of the Whitneyan beteromyid Proheteromys nebraskensis WOOD contains variants of the P/4 with on incipient sagicristid in approximately 18 percent of the population. The upper dentition and lower molars of Proheteromys nebraskensis are sufficiently generalized to indicate probable ancestry to Dikkomys. 


  PV article infos

Published in Vol. 9, Ext (1980)

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Morphotypes dentaires actuels et fossiles des Chiroptères Vespertilioninés. 1e partie: Etude des morphologies dentaires
Henri Menu
Published online: 30/09/1985

Keywords: bats; Dental morphology; fossils; PHYLOGENY; recent; Systematics

https://doi.org/10.18563/pv.15.2.71-128

  Abstract

    The classifications of the recent vespertilionine bats were made wihtout taking in account the teeth morphology; this resulted in a reduction of the possibilities of comparison with the available fossils. The generalized use of dental formulae was abusive: this contributed to the admission of artificial genera. These conditions have long delayed the consideration of characters able to frame the phylogeny of the sub-family. In the first part of the study, the teeth morphologies are described and analysed. morphological reference types are established for each upper and lower tooth: they should make an easier elaboration of criteria for the differentiation at generic level. The position of the species in view of these criteria allows one to group them into homogeneous genera, and to appreciate the degree of relationship that the latter have between them. The second part of the study (next publicationà will develop inferences dealing with systematics and phylogeny 


  PV article infos

Published in Vol. 15, Fasc. 2 (1985)

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Lower Paleogene crocodilians from Silveirinha, Portugal.
Miguel T. Antunes Logo
Published online: 15/10/2003

Keywords: ?Upper Paleocene / Lowermost Eocene; Crocodilians; Ecology; Portugal

https://doi.org/10.18563/pv.32.1.1-26

  Abstract

    The presence at Silveirinha of one of the earliest, ? Late Paleocene or Lowermost Eocene, european representatives of the genus Diplocynodon is based mostly on isolated bones and teeth (often from juveniles). This small-sized form is the only crocodilian so far recognized in this site. The longevity of Diplocynodon in Portugal becomes much extended; the genus survived there until the Middle Miocene at least. A discussion on the possible affinities with other eocene Díplocynodon and especially those from Cubillos-Valdegallina (Zamora, Spain) is presented. On the other hand, differences have been detected in comparison with: Díplocynodon tormis, from the middle Eocene of the Douro basin in Spain, which may belong to another phyletic line; and the aff. Diplocynodon from Dormaal (Belgium) and Le Quesnoy (France), nearly contemporaneous of Silveirinha. The Silveirinha Diplocynodon and many other data strongly suggest moist, subtropical, quite limited in space environments related to an alluvial plain crossed by small, meandering channels. 


  PV article infos

Published in Vol. 32, Fasc. 1 (2003)

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La variabilité morphologique dentaire du Landenodon (Condylarthra) de Dormaal, (Eocène,Belgique)
Marc Godinot Logo
Published online: 01/10/1980

Keywords: Condylarths; Dormaal; Early Eocene; Landenodon

https://doi.org/10.18563/pv.9.ext.167-196

  Abstract

    The study of dental variations in Landenodon from Dormaal (early Eocene, Belgium) shows that only one
    species is present in this locality : L. woutersi QUINET, 1968 (Condylarthra, Arctocyonidae, Arctocyoninae). A high morphological variability is described, especially concerning the metaconid of P/4, the paraconid of M/2, and some characters of M1/ which have been found to be independant of each other. This variability is discussed. 


  PV article infos

Published in Vol. 9, Ext (1980)

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Mammals and stratigraphy : Geochronology of the continental mammal-bearing Tertiary of south America.
Larry G. Marshall, Robert Hoffstetter and Rosendo Pascual
Published online: 15/12/1983

Keywords: Cenozoic; Geochronology; Mammalia; South America; Stratigraphy; Tertiary

https://doi.org/10.18563/pv.13.ext

  Abstract

    The principles and practices employed in establishment and recognition of South American land mammal ages are reviewed along with previous and present concepts of distinguishing time, rock, and faunal units. Previous chronological arrangements of South American Tertiary land mammal faunas are appraised on the basis of recent geological and paleontological data. Twelve South American Tertiary land mammal ages are here recognized [from oldest to youngest, Riochican (middle to late Paleocene); Casamayoran (early Eocene); Mustersan (middle Eocene); Divisaderan (late Eocene); Deseadan (early [to middle?] Oligocene); Colhuehuapian (late Oligocene); Santacrucian (early Miocene); Friasan (middle Miocene); Chasicoan (late Miocene); Huayquerian (latest Miocene); Montehermosan (early to middle Pliocene); and Chapadmalalan (late Pliocene)]. As all except the Friasian were originally defined on the basis of Argentine faunas, these are discussed first and at length, and each is reviewed with discussion of type locality, stratigraphy, type fauna, and faunal correlations. Non-Argentine faunas are then discussed country by country in alphabetical order.

         A review is given of radioisotope dates obtained on volcanic rocks (i.e., basalts, tuffs) associated with mammalbearing beds in Argentina. Based on these age determinations and on correlation of the late Tertiary land mammals involved in the interchange between North and South America, a chronology of South American land mammal ages correlated with North American land mammal ages and European marine stages is proposed.

    It is concluded that South America was an island continent through most of the Tertiary Period (ca 65 to about 3 Ma). As a result, the land mammal fauna of South America developed in isolation and was dominated by autochthonous endemic groups. Toward the end of the Tertiary (i.e., middle Miocene) a unique faunal balance had been achieved by the descendants of the ancient inhabitants (notoungulates, litopterns, condylarths, astrapotheres, edentates, marsupials) and of later (late Eocene) waif immigrants (caviomorph rodents, platyrrhine primates). A prominent feature of this mammal fauna was the combination of carnivorous and omnivorous marsupials with native placental herbivorous ungulates, subungulates, and edentates.

    Sometime during the late Miocene, a limited but important interchange of mammalian taxa between North and South America took place. Procyonids (raccoons and their allies), a group of North American origin, first appear in South America in strata of Huayquerian Age, while members of the extinct South American ground sloth families Megalonychidae and Mylodontidae first appear in North America in early Hemphillian time. These groups dispersed along island arcs before the appearance of the Panamanian land bridge in the Pliocene (ca 3.0 Ma). Cricetine rodents, a group of North American origin, are first known in South America in strata of Montehermosan Age. The known taxa are too advanced and diversified to be considered the first of this group to invade South America. lt is believed by some workers that these rodents arrived before the Montehermosan, possibly in the late Miocene or earlier, by waif dispersal from North America.

    The isolation of South America ended with the appearance of the Panamanian land bridge, which provided a direct, dry land connection between the two Americas. Across this portal an extensive interchange of terrestrial faunas occurred, and the fossil record documents an intermingling of these long-separated land mammals faunas.

          The beginning of this interchange by land route in South America is marked by the appearance of mammals which evolved from North American emigrants in the Chapadmalal Formation of Argentina. These include a mustelid (Conepatus), a tayassuid (Argyrohyus), and four genera (Akodon, Dankomys, Graomys, Reithrodon) of cricetine rodents. The appearance of this contingent of northern animals favors the existence of the Panamanian land bridge by this time. Likewise, a large number of terrestrial vertebrates of South American origin appear in North America in beds of late Blancan Age date around 2.7 Ma. Among the mammals are Neochoerus, Erethizon, Glyptotherium, Glossotherium, Kraglievichia, and Dasypus. 


  PV article infos

Published in Vol. 13, Ext (1983)

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Les Entélodontes des phosphorites du quercy
Michel Brunet Logo
Published online: 15/11/1974

Keywords: Entelodontes; Quercy Phosphorites

https://doi.org/10.18563/pv.6.1-2.87-108

  Abstract

    The entelodonts of the Quercy phosphorites are essentially known from isolated teeth. The skull remains attributed to Entelodon magnum by Kowalewsky in 1876 and the type left mandible of Enteladon depereti RÉPELIN, 1918 do not belong to this family. From a morphologic point of view, the teeth from Quercy are quite comparable to those from the type localities of E. magnum and E. deguilhemi. In the absence of distinctive anatomical criteria between E. magnum (small species from the level of Ronzon) and E. deguilhemi (large species from the level of Villebramar) they are referred, according to their size, to one or the other of these two species. However, some of them are intermediate in size. Their existence speaks in favor of a close relationship between E. magnum and E. deguilhemi and confers a real stratigraphic interest to these entelodonts of Western Europe. Finally, some anatomical characters (notch on the mesial border of P4, presence of a paraconid joined to the metaconid, trigonid higher than talonid) considered until now as peculiar to the North American Archaeotherium and not yet cited in its European contemporary Entelodon have been brought to light on the teeth from Quercy.

      


  PV article infos

Published in Vol. 06, Fasc. 1-2 (1974)

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Diversity among north african dinosaur eggshells.
Monique Vianey-Liaud Logo and Géraldine Garcia Logo
Published online: 15/12/2003

Keywords: Cretaceous; Dinosaurs diversity; Eggshells; Maastrichtian; Morocco; North Africa; taxonomy

https://doi.org/10.18563/pv.32.2-4.171-188

  Abstract

    Until the discovery of dinosaur eggshells locality in the Oukdiksou syncline, (Middle Atlas, Morocco) in 1999 (Garcia et al. this volume) the maastrichtian reptiles faunas were unknown in North Africa. Additional material from Achlouj-2 allows us to describe five oospecies, belonging to four oofamilies. The Megaloolithidae is recorded by Megaloolithus maghrebiellsis Garcia el al. and Pseudomegaloolithus atlasi oogen. novo oospec. nov. Tipoolithus achloujensis Garcia et al. is questionably considered as a Subtiliolithidae. A relatively small Elongatoloolithidae is represented by Rodolphoolithus arioul oogen. nov. oospec. nov. A thin Prismatoolithidae is described as a new oospecies of ? Pseudogeckoolithus Vianey-Liaud & Lopez-Martinez, 1997: P. tirboulensis. The diversity of these oospecies indicates that the dinosaur fauna comprises at least five dinosaur oospecies, with perhaps one sauropod and three theropods. 


  PV article infos

Published in Vol. 32, Fasc. 2-4 (2003)

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Nouvelles espèces de Dendromus (Rongeurs,Muriodea) à Langebaanweg (Pliocène,Afrique du Sud) conséquences stratigraphiques et Paléoecologiques
Christiane Denys Logo
Published online: 20/05/1994

Keywords: Dendromurinae; Paleoecology; Pliocene; Rodents; South Africa; Stratigraphy

https://doi.org/10.18563/pv.23.1-4.153-176

  Abstract

    New Dendromus species (Rodentia, Muroídea) from Langebaanweg (Pliocene, South Africa). Stratigraphical and paleoecological consequences.

    Two new species of Dendromus are described from the Langebaanweg site which precises the evolutionary trend among this genus in South Africa and gives further paleoenvironmental indications. Two evolutionary stages are described: D. darti nov. sp. shows low-crowned molars with bunodont cusps and its more closest relative would be D. melanozis from the Cape region. On the contrary, D. averyi nov. sp. is more lophodont and is better related with the modem D. melanotis. Both species are at a less evolved stage than the Dendromus sp. from Laetolil Beds at Laetoli. The Langebaanweg deposits cannot still be dated by biostratigraphy but they clearly cannot be older than the basis of Pliocene times. The association of Dendromus and Mystromys in the same levels indicates a grassland environment with woodland patches as well as probable swamps. 


  PV article infos

Published in Vol. 23, Fasc. 1-4 (1994)

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Le genre Microstonyx en Espagne et ses relations avec les autres espèces du même genre hors d'Espagne
Juana M. Golpe-Posse
Published online: 01/10/1980

Keywords: Microstonyx; Spain; Suidae

https://doi.org/10.18563/pv.9.ext.213-231

  Abstract

    The genus Microstonyx was found only in the north eastern part of Spain : M. antiquus, referable to the
    Eppelsheim type, from the pyrenean basins ; M. antiquus, more progresive, from the Vallès Basin : M. major-erymanthius group, from the Teruel-Ademuz Area and from Pieru (Penedès Basin).

      


  PV article infos

Published in Vol. 9, Ext (1980)

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La poche à phosphate de Ste-Néboule (Lot) et sa faune de vertebres du Ludien supérieur. 8- Insectivores et Chiroptères.
Bernard Sigé
Published online: 25/09/1978

Keywords: Eocene; Quercy Phosphorites

https://doi.org/10.18563/pv.8.2-4.243-268

  Abstract

    The small insectivorous placental mammals from Ste-Néboule are poorly varied. Two orders of insectivores are documented : the Proteutheria by Pseudorhyncocyon cayluxi (leptictids), the Lipotyphla by Saturninia gracilis and S. beata (nyctitheriids). The bats are only rhinolophoids and mostly hipposiderids. Sufficient populations allow us to restrict the original definitions of three previous species (Hipposideros schlosseri, Palaeophyllophora quercyi, P. oltina). From now, these species can be regarded as monophyletíc. 


  PV article infos

Published in Vol. 08, Fasc. 2-4 (1978)

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Introduction à l'oeuvre scientifique de Donald E. Russell, "gentleman paleontologist"
Marc Godinot Logo and Phillip D. Gingerich Logo
Published online: 16/12/1996

Keywords: D.E.Russell; Eocene; Mammals; Paleocene; Paleontology; synthesis

https://doi.org/10.18563/pv.25.2-4.63-74

  Abstract

    The scientific career of D.E. Russell began with a Pliocene fauna from Oregon, and then turned in the direction of European Paleogene mammals. Field work followed by study of the mammals that were collected, firstly in the Paleocene and later in the early Eocene, greatly rejuvenated learning in this field. Syntheses on the Northwest European Tertiary basin and on European marnmals and stratigraphy came next. Research on the Eocene of Asia was carried out jointly with Gingerich on Pakistan and with Dashzeveg on the faunas of Mongolia. An important synthesis on the entire Paleogene of Asia, joint with Zhai, followed. Field work in Africa with Sigogneau-Russell led to the discovery of Mesozoic mammals there. A synthesis of mammalian paleofaunas of the world was written with Savage, and a similar synthesis of Cenozoic vertebrate faunas is currently being prepared. These achievements reflect the perennial importance of field work, numerous collaborations with both amateurs and professionals, and the human qualities of this author.
      


  PV article infos

Published in Vol. 25, Fasc. 2-4 (1996)

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Perutherium altiplanense, un Notongulé du Cretacé Supérieur du Pérou
Larry G. Marshall, Christian de Muizon Logo and Bernard Sigé
Published online: 30/11/1983

Keywords: Dental morphology; Late Cretaceous; Notoungulate; Paleobiogeography; Peru

https://doi.org/10.18563/pv.13.4.145-155

  Abstract

    Perutherium altiplanerise THALER, 1967 from the Late Cretaceous of Peru has long been recognized as South America's oldest known placental mammal. Since its description Perutherium has been generally regarded as having condylarth affinity Based on our identification  of a unique notoungulate synapomorphy we recognize Perutherium as the oldest and the most generalized known member of that order. This new determination and the large taxonomic diversity (five families) of notoungulates in rocks of Paleocene age in Argentina and Brazil, favor a South American origin for this group. The occurrence of notoungulates in rocks of Late Paleocene age in Asia and North America is explained by dispersal of a notoungulate stock from South America to North America and from there to Asia. 


  PV article infos

Published in Vol. 13, Fasc. 4 (1983)

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La palichnofaune de vertébrés tétrapodes du permien supérieur du Bassin de Lodève (Languedoc-France).
Georges Gand, Jacques Garric, Georges Demathieu and Paul Ellenberger
Published online: 15/09/2000

Keywords: Footprints; France; Languedoc; Lodève basin; new ichnotypus; Saxonian; Upper Permian

https://doi.org/10.18563/pv.29.1.1-82

  Abstract

    Near "la Lieude", in the Lodève basin, more than a thousand of footprints are distributed in a twenty of trackways which amounts to 220 m length. They have been found on calcareous siltstone level in the B site named also "Réserve Naturelle Volontaire". This last is located in the Saxonian summit dated Upper Permian. "La Lieude" tracks are described by using statistical methods then they are compared with others from the world Permian. What allows to distinguish 4 following ichnotaxa: Lunaepes ollierorum nov.ichnosp., Merifontichnus thalerius nov. ichnogen. and nov. ichnosp., Planipes brachydactylus nov.ichnosp. and Brontopus circagiganteus nov. ichnosp. All these traces are attributed with possibility or probability to Therapsida or to Therosauria, except Brontopus circagiganteus nov. ichnosp. that could be due to Caseamorpha. All these animals whose sizes have been estimated between l and 5 m lived probably in a playa environment.The biological and sedimentological data from "la Lieude" footprints levels compared with informations provided by the tracks orientations, suggest the following scenario. Animals coming from the North have crossed a sandy channel bank with plants zones by directing to the South for the majority. Maybe, they were going to the lacustrine part of the playa, close to "la Lieude" footprints that they have just trampled on. 


  PV article infos

Published in Vol. 29, Fasc. 1 (2000)

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Présence de Palaeobatrachidae (Anura) dans des gisements tertiaires Français caractérisation, distribution et affinités de la famille
Colette Vergnaud-Grazzini and Robert Hoffstetter
Published online: 15/05/1972

Keywords: Anura; Palaeogeography; Systematics

https://doi.org/10.18563/pv.5.4.157-177

  Abstract

    The Palaeobatrachidae until now have not been reported from France. The present note makes known the discovery of very significant remains in three Tertiary localities of France: Cernay (late Paleocene), Laugnac (late Aquitanian) and Sansan (middle Helvetian). The osteologic characters, as well as the geographic and stratigraphic distribution of the family are re-stated with added details. The Palaeobatrachidae are a European family known from the late Jurassic of Catalonia (publication in course by J. Seiffert) to the Plio-Pleistocene (pre-Mindel) of Poland and Rumania. By their way of life and certain osteologic characters they are similar to the Pipidae, but they are distinguished by profound differences. It would be rash to include them in the Pipoidea or even in the Aglossa. They are apparently an independant group, essentially holarctic, which held in Europe a role equivalent to that played by the Pipidae south of Tethys. 


  PV article infos

Published in Vol. 05, Fasc. 4 (1972)

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Les artiodactyles du gisement yprésien terminal de Premontre (Aisne, France)
Jean Sudre and Jorg Erfurt
Published online: 16/12/1996

Keywords: Artiodactyls; France; Mammals; new species; Ypresian

https://doi.org/10.18563/pv.25.2-4.391-414

  Abstract

    The artiodactyls (Mammalia) from the latest Ypresian locality of Prémontré from the Paris Basin (niveau repère MP 10 in the lower Eocene of the Paris Basin) are described in this paper. Three species have been identified: 1) Diacodexis cf. varleti SUDRE et al., 1983; 2) a new species of Eurodexis ERFURT & SUDRE (E. russelli nov. sp.) defined after the revision of the species Messelobunodon? ceciliensis from the Lutetian beds of Geiseltal (Germany); and 3) Eurodexeinae indet., a probable ancestor of another form from the Geiseltal which was previously recorded as Homacodon? sp. (Erfurt 1993) and now named Parahexacodus germanicus. The two later forms are referred to the new subfamily Eurodexeinae (Erfurt & Sudre 1996). The analysis of these forms as weIl as comparative studies have led us to reconsider our previous conclusions regarding the content of the species Protodichobune oweni LEMOINE 1878 and some aspects of Ypresian diacodexid evolution. One can postulate that the divergence of E. russelli nov. sp. occurred during the first radiation of these primitive artiodactyls. Some other stem form with bunodont teeth such as Protodichobune and Aumelasia have also differentiated from Diacodexis. Like Eurodexis, these two genera persist during the middle Eocene. The absence of Protodichobune and Aumelasia at Prémontré is probably due to particular ecological conditions. 


  PV article infos

Published in Vol. 25, Fasc. 2-4 (1996)

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Rongeurs caviomorphes de l'Oligocène de Bolivie. 1 Introduction au deseadien de Bolivie
Robert Hoffstetter
Published online: 01/08/1976

Keywords: Rodentia; South America

https://doi.org/10.18563/pv.7.3.1-16

  Abstract

    The Tertiary of the Salla-Luribay basin consists of red beds affected by the second period of the andine compression, of Miocene ending age. The Tertiary layers are exposed at an approximate elevation of 3.500 to 4.000 meters. Two stratigraphic units can be distinguished in them: the Luribay conglomerates, in which vertical clifts result from erosion, and the Salla layers consisting mostly of consolidated clays. These clays are very fossiliferous and have furnished a rich vertebrate fauna which gave to R. Hoffstetter the possibility to establish the Oligocene age of these beds. Sediments of same age has been reported to be present in several other places of Bolivia, particularly near Lacayani, where have been collected highly hypsodont Rodents, different from those found in Salla-Luribay basin. 


  PV article infos

Published in Vol. 07, Fasc. 3 (1976)

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A reassessment of the giant birds Liornis floweri Ameghino, 1895 and Callornis giganteus Ameghino, 1895, from the Santacrucian (late Early Miocene) of Argentina.
Eric Buffetaut Logo
Published online: 13/12/2016

Keywords: Argentina; Aves; Callornis; Liornis; Miocene

https://doi.org/10.18563/pv.40.2.e3

  Abstract

    The status of the giant bird taxa Liornis floweri and Callornis giganteus from the Santa Cruz Formation (late Early Miocene) of Patagonia, first described by Ameghino (1895) is reassessed on the basis of a re-examination of the type material at the Natural History Museum, London. Liornis floweri, which lacks a Pons supratendineus on the tibiotarsus and has an unbifurcated Canalis interosseus distalis on the tarsometatarsus, is clearly a brontornithid and is considered as a junior synonym of Brontornis burmeisteri. Ameghino’s replacement of Callornis by Eucallornis is unjustified. Callornis giganteus is a chimera based on a phorusrhacid tarsometatarsus (probably belonging to Phorusrhacos longissimus) and a brontornithid tibiotarsus. The latter can be considered as the lectotype of Callornis giganteus, which may represent a small morph of Brontornis burmeisteri or a distinct taxon. It is referred to here as Brontornithidae indet. The tarsometatarsus described by Dolgopol de Saez (1927a,b) as Liornis minor and considered by her as a gracile brontornithid apparently has a bifurcated Canalis interosseus distalis and should therefore be placed among the Phorusrhacidae. 


  PV article infos

Published in Vol.40-2 (2016)

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Contribution à la classification des pistes de vertébrés du Trias: Les types du Stormberg d'Afrique du Sud (1).
Paul Ellenberger
Published online: 16/10/1972

Keywords: Footprints; South Africa; Stormberg; Trias

https://doi.org/10.18563/pv.5.ext

  Abstract

    Cet article explore les pistes fossiles de vertébrés du Stormberg (Trias, Afrique du Sud), révélant une diversité ichnologique inédite avec 64 ichnotypes classés en tridactyles, tétradactyles et pentadactyles. Les découvertes incluent des reptiles bipèdes comme Qemetrisauropus et Prototrisauropus, dont les empreintes suggèrent des adaptations évolutives vers la bipédie, ainsi que des pentadactyles géants comme Pentasauropus, annonçant les futurs sauropodes. L’étude combine ichnologie et restes osseux pour reconstituer des écosystèmes triasiques riches, où flore (fougères, conifères) et faune témoignent d’une transition écologique majeure avant l’essor des dinosaures. 


  PV article infos

Published in Vol. 5, Ext (1972)

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Analyse d'ouvrage : A.J.Sutcliffe. On the track of Ice Age mammals
Jacques Michaux
Published online: 30/12/1985

Keywords: Book review

https://doi.org/10.18563/pv.15.4.270

  Abstract

    On the Track of Ice Age Mammals justifie pleinement son titre car l'auteur, Anthony J. Sutcliffe, apporte au lecteur faits et interprétations qui l'amèneront à s'intéresser encore plus au passé récent et à l'avenir de son environnement et à la question de l'impact de l'homme sur la nature. Après les chapitres qui présentent les temps glaciaires et les divers témoignages qui nous en sont parvenus, les cinquième et sixième apportent les informations nécessaires à la compréhension des résultats que nous donnent les chercheurs: principes, moyens d'étude et limites des méthodes, difficultés de l'intégration des données dans un cadre stratigraphique, variabilité des signaux climatiques, variabilité de leur intensité selon l'endroit par rapport au centre de la glaciation, complications liées à la qualité inégale de l'enregistrement géologique, en mer et sur le continent. 


  PV article infos

Published in Vol. 15, Fasc. 4 (1985)

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Sur le remplissage des "poches à phosphorite" d'Aubrelong (commune de Bach, Lot)
Bernard Gèze
Published online: 15/11/1974

Keywords: Aubrelong; Quercy Phosphorites

https://doi.org/10.18563/pv.6.1-2.21-25

  Abstract

    L’article analyse les poches à phosphorite d’Aubrelong (Quercy), comparant les fouilles de 1937 (Éocène supérieur) et celles des années 1967-1970 (Oligocène inférieur), révélant une stratification contrastée : argiles brunes pauvres en fossiles en surface, et argiles rouges riches en phosphates et faune en profondeur. Les analyses géochimiques confirment une origine latéritique sous climat tropical humide, avec des remplissages tantôt stratifiés, tantôt chaotiques, remettant en cause l’hypothèse d’une progression chronologique uniforme des dépôts 


  PV article infos

Published in Vol. 06, Fasc. 1-2 (1974)

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Page 12 of 19, showing 20 record(s) out of 368 total