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Page 15 of 19, showing 20 record(s) out of 368 total

Un Haplobunodontidae nouveau Hallebune krumbegeli nov.gen. nov.sp. (Artiodactyla, Mammalia) dans l'Eocène moyen du Geiseltal près Halle (Sachsen-Anhalt, Allemagne)
Jorg Erfurt and Jean Sudre
Published online: 14/06/1995

Keywords: Artiodactyla; Geiseltal; Germany; Mammal; Middle Eocene; new gen.; new sp.

https://doi.org/10.18563/pv.24.1-2.85-99

  Abstract

    A new genus and species of haplobunodontid artiodactyl, Hallebune krumbiegeli nov. gen. nov. sp., is described from the middle Eocene Geiseltal Fauna (Saxon-Anhalt, Germany). Its stratigraphic range is restricted to the MP 13 ("obere Mittelkohle") of the Geiseltalian. The material consists of seven fragments, representing both upper and lower jaws. It is indicated, that H. krumbiegeli was a small bunodont herbivore. The size and primitive character of the teeth suggest that the genus possibly is directly derived from Diacodexeidae.The new material forms the basis for reinterpreting the haplobunodontid phylogeny. 


  PV article infos

Published in Vol. 24, Fasc. 1-2 (1995)

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Les Tayassuidés des phosphorites du Quercy
Léonard Ginsburg
Published online: 15/11/1974

Keywords: Quercy Phosphorites; Tayassuidae

https://doi.org/10.18563/pv.6.1-2.55-85

  Abstract

    Revision of the Tayassuidae from the old collections of the Quercy leads to interesting facts about taxonomic and phylogenetic problems. It could not have been well done without constant comparison with contemporaneous Tayassuidae from stratified series, as well as with European Miocene Tayassuidae and Hyotheriinae. The result is that only three species are present in the Phosphorites of Quercy: Doliochoerus quercyi FiLHOL (represented by two sub-species: the older, D. quercyi quercyi and the more recent, D. quercyi aquensis), Palaeochoerus gergorianus CROIZET et BLAINVILLE and Palaeochoerus purillus nov. sp. The two former species disappeared with Stampian time, while the third is the direct ancestor of the Aquitanian Palaeochoerus typus POMEL, which became extinct before the beginning of Burdigalian.

    The comparison with Hyotheriinae brought to light new criteria for determinations, based on the study of lower premolars. These observations are condensed in a table of keys for determinations.

    As a result of these studies, it came to light that the Suoidea of the Oligo-Miocene of Europe have never given rise to, except in rare cases, very long lineages. The different forms of pigs are replaced constantly in Europe by the simple game of extinctions and migrations. The reason of that discontinuity is considered here. 


  PV article infos

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

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The endocranial cast and encephalization quotient of Ptilodus (Multituberculata, Mammalia)
David W. Krause Logo and Zofia Kielan-Jaworowska Logo
Published online: 11/02/1993

Keywords: encephaIization quotient; endocranial cast; Montana; Multituberculata; olfactory bulbs; Paleocene; Ptilodus

https://doi.org/10.18563/pv.22.2-3.99-112

  Abstract

    Simpson (1937a) reconstructed the brain of the Paleocene multituberculate Ptilodus as having the olfactory bulbs widest anteriorly, an unusual condition among mammals. Slight preparation and reexamination of the endocast specimens of Ptilodus reveals that the olfactory bulbs in fact taper anteriorly, as in the recently-described endocranial casts of three multituberculate species from the Late Cretaceous of Asia, and as in those of other mammals. The brain of Ptilodus was therefore essentially of the same general pattem as in other multituberculates. Ptilodus differs, however, in having the vermis more deeply inserted between the cerebral hemispheres. Other details concerning the endocast morphology of Ptilodus are clarified.

    The encephalization quotient (EQ) of Ptilodus is recalculated from revised estimates of both endocranial volume and body mass to fall somewhere within a broad range of values; from 0.41 to 0.62 if the olfactory bulbs are included and from 0.37 to 0.55 if they are not. In any case, the relative brain size of Ptilodus is roughly equivalent to that of Chulsanbaatar, the only other multituberculate for which EQ has been calculated, but considerably smaller than that of an average extant mammnal. 


  PV article infos

Published in Vol. 22, Fasc. 2-3 (1993)

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An Australian Miocene Brachipposideros (Mammalia, Chiroptera) related to Miocene representatives from France
Bernard Sigé, Suzanne J. Hand Logo and Michael Archer Logo
Published online: 15/12/1982

Keywords: Australia; bats; Chiroptera; Miocene

https://doi.org/10.18563/pv.12.5.149-172

  Abstract

    A new middle Miocene hipposiderid bat is described from a limestone deposit on Riversleigh Station in north-western Queensland. Hipposideros (Brachipposideros) nooraleebus n. sp. is the first record of this subgenus from anywhere in the world outside of France. The palaeoecological setting of the fossil bats appears to have been a relatively quiet, sunny lime-enriched tropical pool that contained tortoises, crocodiles and fish. It is possible that the bats were washed into the pool from an adjacent cave.
    The Riversleigh bat most closely resembles the French Burdigalian (early middle Miocene) bat H. (B.) aguilari. It is also possible that it may have been closely related to the original Australian hipposiderid stock that ultimately gave rise to the endemic monotÿpic Rhinonycteris aurantius. The disjunct distribution of species of H. (Brachipposideros) suggests that representatives of this subgenus will be found in at least tropical southern Asia. 


  PV article infos

Published in Vol. 12, Fasc. 5 (1982)

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Rongeurs Miocènes dans le valles-Penedes 1 : Les rongeurs de Can Ponsic 1
Jean-Louis Hartenberger and Miquel Crusafont i Pairó
Published online: 20/04/1979

Keywords: Can Ponsic 1; Miocene; Rodents; Valles-Penedes

https://doi.org/10.18563/pv.9.1.1-15

  Abstract

    The rodents from the spanish locality of Can Ponsic 1 bring new data about some rodents species of the beginning of the Upper Miocene in South-West Europe. The criticims made by Mein and Freudenthal about the validity of the species Hispanomys thaleri from Can Llobateres are not justiíied. The study of the anatomy of the skull of Rotundomys from Can Ponsic 1 gives accurate information about the affinity of this genus with Cricetulus, and shows that the hypothesis, according to which Rotundomys is an ancestral form of the Arvicolids, is unlikely. The systematics of Heteroxerus and the phylogeny of the mio-pliocene Muscardinus species are also discussed. The Can Ponsic 1 locality is a little older than Can Llobateres.

      


  PV article infos

Published in Vol. 09, Fasc. 1 (1979)

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Osteology of Prolagus sardus, a Quaternary Ochotonid (Mammalia, Lagomorpha).
Mary R. Dawson
Published online: 21/06/1969

Keywords: Lagomorpha; Ochotonidae; Prolagus

https://doi.org/10.18563/pv.2.4.157-190

  Abstract

    Prolagus sardus is the last representative of the diverse lineages of European endemic ochotonids. It is also the most abundant in the collections. The previous studies made of this species have established rather well its dental morphology, its phylogenetic position, its geographic and temporal distribution, and its intraspecific individual variation. On the other hand, no osteologic study has fully utilized the superb material from Corsica and Sardinia  collected by Forsyth Major.
    Nearly all of the parts of the skeleton are represented in this material; they are here described and figured. Comparisons are made with Ochotona, the only surviving genus of the family, as well as with the living leporids, in particular Romerolagus, Oryctolagus and Lepus. A brief examination of the dentition reveals some particular characters of the incisors. The osteologic study allows limited interpretations to be advanced concerning the posture, mastication. locomotion and some other adaptive features of P. sardus.
    P. sardus appears as an incontestable ochotonid, but it differs from Ochotona by some characters which are found in leporids. Certain of the characters are here judged primitive for lagomorphs. The genus Ochotona therefore can no longer be considered as the image of a primitive lagomorph, because in spite of the lack of cursorial adaptations which differentiate it from leporids, it presents other specializations which are common to it alone. 


  PV article infos

Published in Vol. 02, Fasc. 4 (1969)

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Eggshell microstructure and porosity of the Nicobar scrubfowl (Megapodius Nicobariensis, great Nicobar island, India)
Géraldine Garcia Logo, Ashu Khosla Logo, Ashok Sahni Logo and Monique Vianey-Liaud Logo
Published online: 16/12/2008

Keywords: conductance porosity; eggshell microstructure; incubation conditions; Megapodes

https://doi.org/10.18563/pv.36.1-4.75-88

  Abstract

    The eggshell of Nicobar scrubfowl (Megapodius nicobariensis) is described for the first time. Its egg porosity is calculated and discussed with data from several taxa (another megapode, some extant and fossil reptiles including a titanosaur group) in order to compare incubation types with eggshell structure. Eggshell microstructure reflects first phylogenetic traits and does not seem to have developed major adaptative features due to the incubation conditions, except for the pore canals. 


  PV article infos

Published in Vol. 36, Fasc. 1-4 (2008)

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Cricetid rodents from Siwalik deposits near Chinji village. Part I: Megacricetodontinae, Myocricetodontinae and Dendromurinae.
Everett H. Lindsay Logo
Published online: 15/10/1988

Keywords: Dendromurinae; Megacricetodontinae; Middle Miocene; Myocricetodontinae; Rodents; Siwalik

https://doi.org/10.18563/pv.18.2.95-154

  Abstract

    Seventeen species of cricetid rodent are recognized and described from lower and middle Siwalik deposits in the Potwar Plateau of Pakistan. These species are grouped in three categories, characterized as subfamilies (e. g., Megacricetodontinae, Myocricetodontinae, and Dendromurinae); an additional and more abundant category of rodents from these deposits, the Democricetodontinae, is excluded from this study, and will be described in a later study. Fifteen of the species are new, and four new genera are described. The Siwalik cricetid taxa are : Megacricetodon aquilari, n. sp.; Megacricetodon sivalensis, n. sp.; Megacricetodon daamsi, n. sp.; Megacricetodon mythikos, n. sp.; Punjabemys downsi, n. gen. & n. sp.; Punjabemys leptos, n. gen. & n. sp.; Punjabemys mikros, n. gen. & n. sp.; Myocricetodon sivalensis, n. sp.;  Myocricetodon sp.; Dakkamyoides lavocati, n. gen. & n. sp.; Dakkamyoides perplexus, n. gen. & n. sp.; Dakkamys asiaticus, n. sp.; Dakkamys barryi, n. sp.; Dakkamys sp.; Paradakkamys chinjiensis, n. gen. & n. sp.; Potwarmus primitivus, n. gen.; and Potwarmus minimus, n. gen. & n. sp. This diverse record of middle Miocene small mammals illuminates a profound radiation of cricetid rodents in southem Asia, the effects of which were felt in Europe and Africa as well as the rest of Asia. 


  PV article infos

Published in Vol. 18, Fasc. 2 (1988)

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Mammifères nouveaux de l'Ilerdien des Corbières et du Minervois (Bas-Languedoc, France)
Bernard Marandat
Published online: 04/12/1989

Keywords: Bas-Languedoc; Early Eocene; France; Ilerdian; Mammals; New taxa

https://doi.org/10.18563/pv.19.3.161-167

  Abstract

    Four new taxa (two genera, one subgenus, and four species) conceming the orders Condylarthra, Rodentia, Pantolesta, and an undetermined order from middle and middle/upper Ilerdian localities (lower Ypresian) of the Corbières and Minervois regions (Bas-Languedoc, Southem France) are presented in this short paper 


  PV article infos

Published in Vol. 19, Fasc. 3 (1989)

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A new Ardynomys (Rodentia,Cylindrodontidae) from the Eocene of the eastern Gobi Desert, Mongolia.
Demberelyin Dashzeveg
Published online: 16/12/1996

Keywords: Ardynomys; Eocene; Mongolia; Rodentia; Systematics

https://doi.org/10.18563/pv.25.2-4.339-348

  Abstract

    A partial skull of Ardynomys russelli sp. nov. (Rodentia, Cylindrodontidae) is described. This was collected in the late Eocene of Alag Tsab locality in the eastem Gobi Desert, Mongolia. Ardynomys russelli sp. nov. is characterized by small size, brachyodont molars, and retention of P3. It represents the earliest record of the genus Ardynomys MATTHEW & GRANGER, 1925, in Asia. 


  PV article infos

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

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Analyse d'ouvrage : Koobi Fora Research Project, volume 3. The fossil ungulates: geology, fossil artiodactyls, and palaeoenvironments, édité par John Michael HARRIS, 1991. Clarendon Press, Oxford, xvi + 384 p. ISBN 0-19-857399-5.
Jean Sudre
Published online: 11/02/1993

Keywords: Artiodactyls; palaeovenvironments; Ungulates

https://doi.org/10.18563/pv.22.2-3.138-139

  Abstract

    Avec ce volume se clôture l'étude géologique et paléontologique des sites à hominidés de Koobi Fora. Il fait suite aux deux précédents ouvrages, parus respectivement en 1978 et 1983, consacrés également à l'étude des faunes recueillies sur ces gisements dans le cadre du Koobi Fora Research Project. 


  PV article infos

Published in Vol. 22, Fasc. 2-3 (1993)

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Un nouveau genre de ?Palaeotheriidae (Perissodactyla, Mammalia) décelé dans les phosphorites du Quercy (Eocène supérieur ou Oligocène) d'après un arrière crâne sans dents.
Jean-Albert Remy
Published online: 15/06/1999

Keywords: endocranial cast; Epitympanic sinus; Palaeotheriidae; Paléogène; Quercy Phosphorites; skull anatomy

https://doi.org/10.18563/pv.28.1.75-87

  Abstract

    A rear skull from the Quercy Phosphorites is described. It documents a new perissodactyl genus, likely assignable to the family Palaeotheriidae and probably paleogene of age. Owing to the lack of any tooth, this family assignment remains however somewhat hypothetical. The specimen is firstly characterised by the presence of a wide epitympanic sinus swelling and hollowing the squamosal shell and the post-glenoid process. This cavity might make up a peculiar pattern of improvement for the hearing apparatus by carrying out a kind of drum near the middle ear, whereas the bony tympanic remains barely bulged and forms but a few developed auditory bulla. This pattern appears an outcome of a trend observed with many palaeotheriids, such as Plagiolophus. Furthermore, the endocranial cast shows a rather high degree of gyrencephaly for a paleogene mammal. The prominent lambdoidal crest points out a powerful nape musculature and a lowered head bearing. Consequently, it is assumed that such an animal was probably living in somewhat open places, at the expense of rather tough vegetables. It might have been accordingly provided with a semi-hypsodont, cement covered, "plagiolophoid" dentition. 


  PV article infos

Published in Vol. 28, Fasc. 1 (1999)

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L'anatomie de Lyrocephaliscus euri (wiman), Trématosaure du Trias inférieur du Spitsberg : arrière-crâne, squelette axial et ceinture scapulaire.
Jean-Michel Mazin Logo and Philippe Janvier Logo
Published online: 30/06/1983

Keywords: skull anatomy; Spitsbergen; Trematosaurs; Trias

https://doi.org/10.18563/pv.13.1-2.13-31

  Abstract

    The formic acid preparation of a nodule collected from the Lower Triassic of Spitsbergen, and containing a skull with some associated postcranial elements of Lyrocephaliscus euri (WIMAN), precises and enriches previous descriptions of the reputedly well-known trematosaur. lt permits more detailed descriptions of the occipital region, of the course of the carotid arteries and collateral vessels, and refutes the previous description of a stapedial foramen in trematosaurs. The discovery of pleurocentres associated with the other vertebral components confirms the primitive rhachitomy of trematosaurs. 


  PV article infos

Published in Vol. 13, Fasc. 1-2 (1983)

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Les mammifères Montiens de Hainin (Paléocène moyen de Belgique) Part II : Les Condylarthres
Jean Sudre and Donald E. Russell
Published online: 30/12/1982

Keywords: Belgium; Condylarths; Louisininae; Oxyclaeninae; Paleocene

https://doi.org/10.18563/pv.12.6.173-184

  Abstract

    The Condylarths from Hainin (Hainault, Belgium) show no affinity at the generic level to those known in other Paleocene localities of Europe and North America ; they are described as new forms : Monshyus praevius n. gen., n. sp. and Prolatidens waudruae n. gen., n. sp. Monshyus praevius, discovered in only one of the levels in the excavation at Hainin, is similar to the genera Microhyus TEILHARD and Louisina RUSSELL ; with them it is included in the subfamily Louisininae (Hyopsodontidae). With respect to Microhyus and Louisina, Monshyus is distinguished by the precociously modern aspect of its upper molars, the only teeth that are referable. Prolatidens waudruae, known only by lower molars, was found in several levels in the pit at Hainin. It is an arctocyonid presenting possible relationships to the North American form Oxyprimus galadrielae ; it therefore has been provisionally attributed to the subfamily Oxyclaeninae. If this attribution is confirmed, this species will constitute the first and only representative of the group in Europe. 


  PV article infos

Published in Vol. 12, Fasc. 6 (1982)

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Etude des dents jugales inférieures des Equus (Mammalia, Perissodactyla) actuels et fossiles
Véra Eisenmann
Published online: 15/04/1981

Keywords: Cheek teeth; Equus; Mammals

https://doi.org/10.18563/pv.10.3-4.127-226

  Abstract

    The comparative morphology and biometry of the lower cheek teeth of modern Equus are studied on approximately 300 mandibles belonging to the 10 usually recognised species : Equus grevyi, E. burchelli, E. quagga, E. zebra, E. africanus, E. asinus, E. hemionus, E. klang, E. przewalskii, E. caballus. The studied parameters comprise : occlusal length and width, postflexid length and index ; shape of the double knot (metaconid + metastylid + lingual groove) ; depth of the vestibular groove on the molars ; frequency of the pli caballinid, protostylid and other enamel plications or islets ; frequency of the dP/l.
    The same methods of study are applied to a number of North American, Eurasian and African species. For the sake of comparison, some Hemphillian equids were observed (Dinohippus interpolatus, Dinohippus leidyanus, Astrohippus ansae, Phiohippus mexicanus) but most of the discussed material belongs to Pliocene or Pleistocene species of Equus : the « stenonine ›› E. stenonis, E. simplicidens, E. sanmeniensis and E. teilhardi; the « caballine ›› E. scotti, E. lambei, E. Iaurentius, E. mosbachensis, E. germanicus, E. gallicus, E. taubachensis and the Liakhov horse. The relationships of other species, in particular the North American E. calobatus, E. occidentalis, E. cf mexicanus are not clear for the moment. ln Africa, the Plio-Pleistocene species from Koobi Fora (Kenya) show some stenonine and perhaps asinine affinities. The relationships of E. numidicus and E. tabeti are uncertain but these species are probably related to the East African ones. E. mauritanicus is most certainly related to the Quagga group.
    The biometrical data are gathered in 32 tables ; 4 photographie plates and 19 figures illustrate the next. The whole is a complement of the previously published studies of the skulls, upper cheek teeth, incisors and metapodials of modern and fossil Equus.

      


  PV article infos

Published in Vol. 10, Fasc. 3-4 (1981)

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Sur la présence de dents de mammifères (Creodonta, Perissodactyla) près de la limite Paléocène-Eocène à Hoegaarden, Belgique
Richard Smith and Jerry J. Hooker
Published online: 16/12/1996

Keywords: Belgium; Creodonta; Landenian; Mammals; Perissodactyla

https://doi.org/10.18563/pv.25.2-4.115-124

  Abstract

    Amongst a collection of selachian teeth made at Hoegaarden in a marine level of Bruxellian (Lutetian) age, containing a reworked Landenian (Sparnacian) fauna mixed with a contemporaneous one, a few teeth of  terrestrial mammals have been discovered. They comprise two rare European taxa: ? Hallensia sp. and Palaeonictis gigantea, both known from the Landenian. Even though the ?Hallensia has not been definitely identified, il differs from the only perissodactyl of this age previously recorded from Belgium (Cymbalophus cuniculus). 


  PV article infos

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

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Rongeurs de l'Oligocène moyen provenant de nouvelles fouilles dans les phosphorites du Quercy
Monique Vianey-Liaud Logo
Published online: 15/09/1969

Keywords: Oligocene; Quercy Phosphorites; Rodents; Theridomys

https://doi.org/10.18563/pv.2.5.209-239

  Abstract

    A recent campaign of excavations (1965-68) undertaken by the Laboratoire de Paléontologie of Montpellier in pockets of the Quercy phosphorites, has permitted the dating of several localities thanks to the analysis of their micromammalian fauna.
    The rodents of localities belonging to the middle Oligocene (La Sauvetat zone) are the object of this study. This rodent fauna has been compared to the forms coming from three stratified localities belonging to the biochronologic zone of La Sauvetat :  Balm, Montalban and Lovagny.
    The abundance of material, notably of theridomyids and cricetids, permitted a summary statistical study to be effected and gave some precise details on the variability of the species (Theridomys varians in particular). Other details were provided on certain groups, notably on the upper teeth of Scíuromys cayluxi and on the milk teeth of theridomyids. Some specimens of «Sciurus» sp. and of Plesispermophilus angustidens were collected. By this means, it has been possible to establish, for the first time, a precise upper limit to the epoch of their appearance in Europe. 


  PV article infos

Published in Vol. 02, Fasc. 5 (1969)

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 Contributions à l'étude de l'anatomie crânienne des rongeurs. 1- Principaux types de cricétodontinés
Jean-Louis Hartenberger
Published online: 25/09/1967

Keywords: Cricetodon; Cricetodontinae; Miocene

https://doi.org/10.18563/pv.1.2.47-64

  Abstract

    Description, for the first time, of the skull of Ruscinomys Depéret on the basis of a nearly complete specimen, and description of a new facial part of a Megacricetodon Fahlbusch skull (material from upper Miocene, Spain). New description of the skull (facial part) of " Cricetodon" incertum Schlosser on the basis of the specimen from the Oligocene of Quercy phosphorites already published by S. Schaub.
    Comparison of the skull of “ C. ” incertum with that of the asiatic genus Cricetops Matthew and Granger and that of the North-American Eumys Leidy. These three genera of similar age display very distinct characteristics; their common origin must go back to the Eocene, as Wood believed.
    Comparisons of the auditory regions of Ruscínomys and of Megacricetodon where important differences are noted. Comparison of the Cricetodontines from European Miocene with contemporary Cricetines. Contrary of the opinion held by Schaub, their anatomical differences do not seem suflicient to warrant the contention that none of the Cricetines derive from a form close to one of the known Cricetodontines. 


  PV article infos

Published in Vol. 01, Fasc. 2 (1967)

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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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Les Issiodoromyinae (Rodentia, Theridomyidae) de l'Eocène supérieur à l'Oligocène supérieur en Europe occidentale
Monique Vianey-Liaud Logo
Published online: 15/05/1976

Keywords: climate; Faunal turnover; Paléogène

https://doi.org/10.18563/pv.7.1-2.1-115

  Abstract

    Based on material from 30 localities, morphologic dental, cranial and biometric analyses have permitted the characterization of two parallel Issiodoromyine lineages, and also the definition of diverse species representing several evolutive stages. Thus it is that new lineages complete the contribution made by the Theridomyinae and Cricetidae and permit, for the Quercy in particular, additional precision in the biochronologic succession of the localities. One of the lineages is limited to the genus Pseudoltinomys LAVOCAT; the other evolves from the genus Elfomys HARTENBERGER to the genus Issiodoromys BRAVARD in GERVAIS. The latter is affected by profound anatomical changes due to a functional modification of the mastication apparatus. These changes seem to be able to be put in relation with the aridification and cooling of the climate at the end of the Eocene. At the end of the middle Oligocene, a new chewing structure is achieved. It is found in diverse living rodents that inhabit a rather arid steppe environment (Cavia, Pedetes, Ctenodactylus). To these supposed nearby ecologic conditions, these rodents have responded in a convergent fashion. It is possible to attribute to the extreme specialization of Issiodoromys its incapacity to adapt to the new climatic crisis of the end of the Oligocene. The arrival of immigrants may be considered as another cause of its disappearance at this time, complementary or not with the first. 


  PV article infos

Published in Vol. 07, Fasc. 1-2 (1976)

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Page 15 of 19, showing 20 record(s) out of 368 total