Current issue


2025-12
48-2
<< prev. next >>

Print ISSN: 0031-0247
Online ISSN:
2274-0333
Frequency: biannual

Article Management

You must log in to submit or manage articles.

You do not have an account yet ? Sign up.

Most downloaded articles (last month)


Page 7 of 19, showing 20 record(s) out of 365 total

Anatomie du membre antérieur chez un chiroptère Molossidé (Tadarida sp.) du Stampien de Cereste (Alpes-de-Haute-Provence).
Bernard Sigé
Published online: 01/01/1971

Keywords: Chiroptera; Molossidae; Oligocene

https://doi.org/10.18563/pv.4.1.1-38

  Abstract

    The present study describes in detail the anterior limb osteology of a molossid chiropteran of the genus Tadarida, from Céreste, a Stampian locality in the Apt-Forcalquier Oligocene basin already known for its fishes, plants and insects.

    A comparision with the Miocene forms T. srehlini from Saint-Géraud localities and T. sp. from Württemberg, also with the recent forms T. teniotis and Eumops perotis, does not show any clear morphological differences between the Tertiary and Recent Tadarida, indicating a rather noticeable anatomical stability, not exceptionnal indeed among Chiropterans. The Céreste fossil exhibits however slightly primitive wing proportions if compared to the Saint Gérand Aquitanian species.

    Several remarks deal with the peculiar relationships between the ecology of the molossids and their kind of fossilisation, frequently associated with sedimentary facies of the lacustrine type.
      


  PV article infos

Published in Vol. 04, Fasc. 1 (1971)

PDF
Batoids (Rajiformes, Torpediniformes, Myliobatiformes) from the Sülstorf Beds (Chattian, Late Oligocene) of Mecklenburg, northeastern Germany: a revision and description of three new species
Thomas Reinecke
Published online: 24/06/2015

Keywords: Batoids; Chattian; Elasmobranchii; North Sea Basin; Oligocene

https://doi.org/10.18563/pv.39.2.e2

  Abstract

    Bulk-sampling of fossil-rich tempestites from the Chattian Sülstorf Beds of
    Mecklenburg, north-eastern Germany, yielded a rich selachian fauna in which batoids
    predominate by the abundance of teeth but are subordinate by the number of taxa. Thirteen
    taxa are identified, among which rajiform batoids are the most diverse (six species). One
    genus and three species are newly described: Raja thiedei sp. nov., Oligoraja pristina gen. et
    sp. nov., and Torpedo chattica sp. nov. Two species are reallocated: Atlantoraja cecilae
    (Steurbaut & Herman, 1978) new comb., and Dipturus casieri (Steurbaut & Herman, 1978)
    new comb. Ontogenetic heterodonty is documented for the first time in the dental pattern of
    Myliobatis sp. Stratigraphical ranges of batoid taxa in the period from Rupelian to Langhian
    are presented and partly discussed in context with the palaeoclimatic evolution and
    palaeogeographic situation of the North Sea Basin. 


  PV article infos

Published in Vol.39-2 (2015)

PDF
A new study of the anthracotheres (Mammalia, Artiodactyla) from pondaung formation, Myanmar: systematics implications
Aung N. Soe
Published online: 16/12/2008

Keywords: Anthracohyus; Anthracokeryx; Anthracotherium; Pondaung Formation; sexual dimorphism; Siamotherium; South East Asia; taxonomy

https://doi.org/10.18563/pv.36.1-4.89-157

  Abstract

    Anthracotheres from the Pondaung Formation, Myanmar, are considered as one of the most primitive artiodactyl groups and they represent the oldest known record in the world. Thus, the understanding of this group has numerous implications for evolutionary biology and biochronological correlations. However, the systematlcs of these mammals has been interpreted in different ways, and the main debate focuses on the number of taxa represented in the Pondaung Formation. The revised taxonomy proposed here is mainly based on the relative development of the upper molar W-shaped ectoloph, system of crests and stylar cusps, and on body size. On the basis of these characters, they are classified into four genera including six different species. Two well-known genera, Anthracotherium and Anthracokeryx, are validated and more precisely diagnosed. Anthracokeryx possesses a better developed W-shaped ectoloph, system of crests and stylar cusps than Anthracotherium, which displays notable differences with the more derived representatives of this genus. Both of these Pondaung genera show evidence for sexual dimorphism. However, the incompleteness of fossil material fueled a debate concerning the status of two additional Pondaung anthracotheres, Siamotherium and Anthracohyus. The latter genus is of uncertain affinities, but it has been considered as a hippopotamid ancestor. Despite new material attributed to these two forms, additional discoveries are still required to establish their taxonomic status. The hypothesis that Southeast Asia was the centre of origin of Anthracotheriidae is supported by the retention of numerous primitive dental characters in these taxa and by the antiquity of the Pondaung Formation, to which an age of 37 My is now generally accepted. 


  PV article infos

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

PDF
A new Desmodillus (Gerbillinae, Rodentia) species from the early Pliocene site of Langebaanweg (South-western Cape, South Africa)
 
Christiane Denys Logo and Thalassa Matthews Logo
Published online: 20/01/2017

Keywords: Lower Pliocene; Muridae; Rodentia; RSA

https://doi.org/10.18563/pv.41.1.e1

  Abstract

    Situated in the Cape region of the Republic of South Africa (RSA), the paleontological site of Langebaanweg is dated to 5.1 Myr and is famous for having yielded an abundant vertebrate assemblage, including numerous rodent species from the Mio-Pliocene transition. Based on molar morphology and skull anatomy, the single Gerbillinae taxon identified at Langebaanweg and described in this paper is allocated to Desmodillus, which is a modern monotypic South African endemic genus. It is significant in being the oldest representative of the genus in Africa. We describe here a new species of this genus which is larger than the modern D. auricularis, but nevertheless retains some of its main characteristics, namely the shape of the maxilla and mandible, the presence of poorly fused alternating cusps, and no longitudinal crest. This taxon differs from modern South African Gerbilliscus representatives in some mandibular and maxillary characters, in the m1 prelobe cusp, and in having less fused cusps. Two fossil Gerbillinae discovered in the Upper Miocene of Africa and Asia, Abudhabia and Protatera, have been compared with the new species. We discuss their relationships with modern and Plio-pleistocene Gerbillinae and conclude that Abudhabia could be the sister taxon of Desmodillus and that around 6-5 Myr a vicariance event allowed Gerbillinae to diversify into modern Desmodillus in South Africa, and Gerbilliscus in East Africa. The murine/gerbilline ratio, which is a good indicator of rainfall, supports other proxies which suggest that at 5.1 Myr the climate in the Langebaanweg region was more humid than today. 


  PV article infos

Published in Vol 41-1 (2018)

PDF
S.I. Data
La poche à phosphate de Ste-Néboule (Lot) et sa faune de vertebres du Ludien superieur. 14 - Conclusions générales
Jean-Louis Hartenberger
Published online: 25/09/1978

Keywords: Eocene; Quercy Phosphorites

https://doi.org/10.18563/pv.8.2-4.319-326

  Abstract

    Le matériel provenant de nouvelles fouilles dans les phosphorites du Quercy, soumis aux divers spécialistes, a conduit à la soutenance de plusieurs thèses d'état: sur les rongeurs (Hartenberger, Vianey-Liaud), les Chiroptères et Insectivores (Sigé), les Artiodactyles (Sudre), les Squamates (Rage) et, en partie, les Chéloniens (De Broin). Chacun dans son domaine, à côté des conclusions d'ordre évolutif, paléogéographique ou paléoécologique, a pu établir des successions stratigraphiques des gisements du Quercy qui se sont révélées largement concordantes. Ainsi la succession des faunes du Quercy est actuellement l'une des mieux établies. Dans ce contexte, les différents spécialistes ont décidé de conjuguer leurs efforts dans l'étude monographique de plusieurs gisements repérés le long de cette échelle, afin de rassembler l'information paléontologique sur des faunes bien précises et de tenter d'obtenir des indications d'ordre taphonomique. 


  PV article infos

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

PDF
La poche à Phosphate de Ste-Néboule (Lot) et sa faune de vertébres du Ludien supérieur. 5-Squamates
Jean-Claude Rage Logo
Published online: 25/09/1978

Keywords: Eocene; Quercy Phosphorites

https://doi.org/10.18563/pv.8.2-4.201-215

  Abstract

    The Squamates from Sainte-Néboule are charateristic of the Upper Eocene from the Phosphorites du Quercy. Most genera known from this locality do not survive the « Grande Coupure ». Cadurcoboa insolita gen. nov., sp. nov. is a small Boidae very characteristic of the Upper Eocene. 


  PV article infos

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

PDF
Rongeurs (Mammalia, Rodentia) du Miocène de Beni-Mellal
Jean-Jacques Jaeger Logo
Published online: 15/02/1977

Keywords: Morocco; Neogene

https://doi.org/10.18563/pv.7.4.91-125

  Abstract

    The rodent fauna of Beni-Mellal is characterized by the abundance of ctenodactylids and cricetids. The latter are represented by four distinct species, among which a new form. Dakkamys zaiani nov. gen., nov. sp. is described. A detailed morphological analysis shows that, contrary to that which had been established before, « Cricetodon ›› atlasi Lavocat, 1961, is not closely related to any European form known; this species is attributed, in consequence, to the new genus Mellalomys. A simple biometric analysis has shown that the genus Myocricetodon Lavocat, 1952, is represented in this locality by two distinct species. The systematic homogeneity of the Beni-Mellal cricetids is also demonstrated: they can, as a matter of fact, all be referred to the subfamily Myocricetodontinae. The definition of this subfamily is completed. The sciurids and glirids are also reviewed in the light of new systematic and biogeographic information established ln Europe. A new species of Atlantoxevus from the early Pleistocene of Morocco, A. huvelini nov. sp., is described. It is probably the descendant of A. tadlae from Beni-Mellal. Biogeographic analysis leads one to consider this fauna as the result of geographic isolation in the Maghreb since the late Oligocene or the early Miocene. In particular no direct European influence can be discerned. Stratigraphic considerations resulting from the discovery of new localities in North Africa lead to the confirmation of the ante-Vallesian age of this fauna and to its parallelism with the faunas of La Grive in Western Europe and Fort Ternan in East Africa. The peculiar geologic nature of this locality is discussed.
      


  PV article infos

Published in Vol. 07, Fasc. 4 (1977)

PDF
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)

PDF
Les Dipodidae (Mammalia, Rodentia) d'Europe occidentale au Paléogène et au Néogène inférieur: origine et évolution.
Marguerite Hugueney and Monique Vianey-Liaud Logo
Published online: 01/10/1980

Keywords: Dipodidae; Late Oligocene; Quercy Phosphorites

https://doi.org/10.18563/pv.9.ext.302-342

  Abstract

    The study of three new populations of Plesiosminthuspromyarion from the "phosphorites du Quercy" and of material from "Auvergne" brings new data on european oligocene Dipodidae. They appear in Western Europe at the beginning of late Oligocene. Evolutionary trends of the group are drawn and particularly the emergence of morphotypes announcing P. schaubi, from the Coderet level, is revealed among the most recent populations of P. promyarion. Differences are attempted to be drawn between the three species : P. promyarion, P. myarion and P. schaubi by restudying the type-population of P. myarion from the aquitanian deposits of Chavroches (Allier) in comparison with two other populations from the same age and the same region. Relationships between early european, american and asiatic Dipodidae are discussed. 


  PV article infos

Published in Vol. 9, Ext (1980)

PDF
L'occlusion dentaire chez Peradectes, Amphiperatherium et Peratherium, Marsupiaux du tertiaire d'Europe.
Jean-Yves Crochet
Published online: 01/10/1980

Keywords: Didelphidae; Eocene; Mastication; Oligocene; Wear facets

https://doi.org/10.18563/pv.9.ext.79-89

  Abstract

    The general principles guiding the study of wear facets which develop during mastication in mammals possessing tribosphenic molars are named. The application of this method of study to the molars of European Tertiary Didelphidae shows that the lineage of this family as represented by the species Peratherium cuvieri (Upper Eocene), P. elegans (Lower-middle Oligocene) and P. antiquum (Upper Oligocene) has propessively evolved toward a more carnivorous diet. 


  PV article infos

Published in Vol. 9, Ext (1980)

PDF
Types dentaires adaptatifs chez les sélaciens actuels et post-paléozoïques.
Henri Cappetta Logo
Published online: 01/09/1986

Keywords: Dental types; evolution; Fossil selachians; Recent selachians; Trophic adaptations

  Abstract

    The dentition of selachians is characterized by an often very pronounced heterodonty involving a great morphological diversity. Despite this fact, the dentitions of selachians can be grouped in a rather reduced number of dental types corresponding to trophic adaptations: grasping, tearing, cutting, crushing, grinding and grasping-grinding type. The numerous exemples of convergence and parallelism that can be observed in fossil selachians and between Recent and fossil ones is the result of this reduced number of dental types. These dental specialisations allow to try a reconstruction of the way of life of fossil forms. 


  PV article infos

Published in Vol. 16, Fasc. 2 (1986)

PDF
Contributions à l'étude du gisement Miocène supérieur de Montredon (Hérault). Les grands mammifères. 7 - Les proboscidiens Deinotheriidae
Heinz Tobien
Published online: 15/11/1988

Keywords: allometry; Astaracian; Deinotherium; Montredon; Systematics; taphonomy; Vallesian

  Abstract

    Some complete tooth rows and about one hundred isolated teeth enabled the identification of the deinothere of the Vallesian site Montredon (Hérault) as Deinotherium giganteum KAUP 1829, mainly by comparisons with the likewise Vallesian sample of the type locality Eppelsheim (Rheinhessen, F.R.G.).
    Scatterdiagrams of the teeth show the importance of allometry during the phyletic size increase of the European deinotheres.
    Some taphonomic problems of the Montredon deinothere are briefly mentioned. 


  PV article infos

Published in Vol. 18, Ext (1988)

PDF
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)

PDF
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)

PDF
Agriotherium intermedium (Stach 1957) from a Pliocene fissure filling of Xiaoxian County (Anhuei Province, China) and the phylogenetic position of the genus.
Zhanxiang Qiu and Norbert Schmidt-Kittler
Published online: 30/09/1983

Keywords: Carnivora; China; PHYLOGENY; Pliocene; skull anatomy; Ursidae

https://doi.org/10.18563/pv.13.3.65-81

  Abstract

    A fragmentary mandible and maxilla of a small sized Agriotherium of a young individual discovered from a Pliocene fissure filling in Xiaoxian county (Anhuei Province, China) are described. Judging from the morphology of the dentition and its dimensions the new material can be identified as Agriotherium inlermedium (STACH l957). Hendey's proposition (1980) that the Agriotherium species are derived from Indarctos is reconsídered on the basis of the new documents. As a result of a more general phylogenetic discussion it can be stated, that: 1. the supposed size increase as well as other trends, leading from Indarctos to Agriotherium are untenable ; 2. there are no positive indications to assume a phylogenetic transition of these two genera. 3. there are no real arguments in favor of an adaptational reversal in the evolution of Agriotherium. Hence, many features of that genus supposed by Hendey to be derived are plesiomorphic ; 4. regardless of the previous points it is methodologícally impossible to establish direct ancestor - descendant relationships between Indarctos and Agriotherium species, as Hendey did. Based on the data available and especially on the characters of the new material from China it is more likely that Agriotherium and Indarctos are two genera which developed independently. While advanced Agriotherium species, e.g. A. africanum, resemble in some respects Indarctos by adaptational analogies, more primitive species, e.g. Agriotherium intermedium, are quite dissimilar to lndarctos. While Indarctos might be derived from an Ursavus like forerunner, Agriotherium has its roots more likely somewhere in between Ursavus and the Hemicyon-group. 


  PV article infos

Published in Vol. 13, Fasc. 3 (1983)

PDF
Contributions à l'étude des micromammifères du gisement Miocène supérieur de Montredon (Hérault). 4 - Les chiroptères
Bernard Sigé
Published online: 30/06/1982

Keywords: Chiroptera; Hérault; Late Miocene; Micromammals; Montredon

https://doi.org/10.18563/pv.12.3.133-140

  Abstract

    The Montredon local fauna yielded very rare bats, represented by damaged isolated teeth. Only a few documents are available for this period of the European Neogene. ln this poor state of knowledge, the material represents three undetermined species, a supposed molossid and two vespertilionids. 


  PV article infos

Published in Vol. 12, Fasc. 3 (1982)

PDF
Comparative bone histology of rhabdodontid dinosaurs
Edina Prondvai Logo
Published online: 17/11/2014

Keywords: bone histology-based ontogeny; Mochlodon; Rhabdodon; skeletal maturation; Zalmoxes

https://doi.org/10.18563/pv.38.2.e1

  Abstract

    A comparative bone histological study of the three known genera of the endemic European ornithopod dinosaur family, Rhabdodontidae, is presented here in an ontogenetic context. Investigated specimens were assigned to different ontogenetic stages based exclusively on the histological indicators of osteologic maturation during diametrical bone growth; an entirely size-independent method as opposed to most previous studies. Qualitative comparison of bone histology of corresponding ontogenetic stages and elements among the three valid rhabdodontid genera, Mochlodon, Zalmoxes, and Rhabdodon, revealed some consistent patterns. Genus specific histological differences within Rhabdodontidae are most expressed between Rhabdodon and the Mochlodon-Zalmoxes clade. These indicate a prolonged phase of fast growth and a less constrained cyclicity in the growth dynamics of Rhabdodon, as opposed to the slower and more regulated growth strategy reflected in the bones of Mochlodon and Zalmoxes. These genus specific differences are consistent with the phylogenetic interrelation of the genera and are most probably related to the pronounced differences in body size. However, when compared to other ornithopods, most detected histological features in rhabdodontids do not seem to reliably reflect either phylogenetic relations or body size. A notable common feature of all rhabdodontid genera irrespective of body size is the ontogenetically early onset of cyclical growth and secondary remodelling; a pattern that more resembles the condition found in derived ornithopods than that described in more basal taxa which are closer relatives of rhabdodontids. The recognition of taxon-specific histological patterns as well as patterns indicative of ecological and thereby functional traits clearly requires more accurate, preferably quantitative evaluations.   


  PV article infos

Published in Vol.38-2 (2014)

PDF
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)

PDF
Le genre Plagiolophus (Palaeotheriidae, Perissodactyla, Mammalia): révision systématique, morphologie et histologie dentaires, anatomie crânienne, essai d'interprétation fonctionnelle
Jean-Albert Remy
Published online: 15/12/2004

Keywords: New taxa; Paléogène; perissodactyls; skull anatomy; tooth histology

  Abstract

    The genus Plagiolophus is documented, almost solely in Western Europe, from the middle Eocene up to the mid Oligocene (MP 12 to MP 25), i.e. more than for 15 MY. Seventeen species are now recorded whose two of them are new, P. ringeadei nov. sp. and P. mamertensis nov. sp. Some anatomical variations and the deflection of certain evolutionary trends justify the distinction of three subgenera, Paloplotherium, Fraasiolophus nov. and Plagiolophus s.s. The genus displays a wide range in size and weight (between 10 and 150 kg). The detailed description of the skull of several species is here given for the first time.
    Despite important evolutionary drifts during this long time span, the dentition shows a great structural homogeneity, which renders difficult the determination of fragmentary specimens or isolated teeth. It is characterized by a great heterodonty; premolars are little molarized and present a certain regression through time with paradoxically some progress in the molarization. The hypsodonty increases: the first Plagiolophus are hardly less brachyodont than Propalaeotherium, and the last ones are nearly as hypsodont as Merychippus from the early Miocene. The upper molars change from a wide crown pattern, with an open occlusal surface, lightly oblique transverse lophs and rounded internal cusps, to a narrower pattern, with a frontally constricted occlusal surface and internal lophs aligned parallel to the ectoloph. The M3/3 become always longer.

    The dental enamel displays horizontal Schreger-bands with imprecise limits occupying only the middle part of the enamel layer. The dentine is remarkable by its high rate of pericanalicular dentine. The crown cementum, lacking in earlier forms, increases to the point where it fills the occlusal valleys of the
    teeth.

    The masticatory musculature shows a increasing prominence of the temporal, with probably an important role devoted to the pterygoid muscles in lateral movements related to a two-phase type of chewing.

    The evolution of the dentition, of the masticatory musculature and of the repartition of masticatory forces indicate that the Plagiolophus have known different diets through their long evolutionary history; at first browsers they became mixed feeders and finally grazers. Their relatively long neck allowed these animals to reach different vegetal layers. The strength of the nuchal crests also suggests that they were able to have strong backwards movements of the head to pull up their food.

    This evolution of diet seems related to the slow degradation of environmental conditions attested during this period in western Europe, with the generalization of more open landscapes, increasing aridity and more marked seasons.

    Besides, a remodeling of the face is ontogenetically and along time observed, in relation with the evolution of the masticatory apparatus and especially with that of the mandibular lever arm. The postcanine diastemata become longer in the course of evolution; the free extremities of the nasals are always relatively long which contradicts the hypothesis according to which Paloplotherium may have had a trunk. At last the lineage Fraasiolophus can be distinguished by the presence of a deep malar fossa, probably related to a strong development of the maxillo-labialis superior muscle.

    The orbit is always large and tends to increase in size, which indicates a good development of the vision and its increasing role in the life relations. A peculiar type of epitympanic sinus could have been used as a resonance chamber insuring a certain amplification of sounds before their transmission to the eardrum. The endocranial cast reveals a relatively large brain with an advanced degree of gyrencephaly. Beside the role eventually played in food research and social relations, these neurophysiological abilities, also related to an advance in cursorial fitness, could have contributed to the survival of these animals facing the predation pressure of the first fissipede carnivores and the competition with new immigrant herbivores after the "Grande Coupure".
    On the basis of some shared apomorphies with the Pachynolophinae, which prevent from considering the latter as Equidae (molarization of the premolars, reduction of the premaxilla dorsal apophysis, peculiar epitympanic sinus, splitting of the jugular process), the hypothesis of an autochthonous origin of Plagiolophus issued from a form near Propalaeotherium, is once again proposed and discussed. Finally, intra-generic relationships are taken into consideration. 


  PV article infos

Published in Vol. 33, Fasc. 1-4 (2004)

PDF
The Pleistocene vertebrate fauna of Robinson Cave, Overton County, Tennessee
J. E. Guilday, H. W. Hamilton and A. D. Mc Crady
Published online: 20/01/1969

Keywords: Fauna; Mammalia; Pleistocene; Tennessee

https://doi.org/10.18563/pv.2.2.25-75

  Abstract

    A late Pleistocene deposit of 60 species of vertebrates and 12 of invertebrates is described from Robinson Cave, Overton County, Tennessee, U.S.A. Forty-eight species of mammals are represented by at least 2,483 individuals; 10 % are extinct, 10 % occur in the state only as boreal relicts in the Great Smoky Mountains; 23 % no longer occur as far south as Tennessee; 57 % occur at or near the site today. Nínety-one percent of the Recent mammal species can be found living today in the Minnesota-Wisconsin area, approximately 10 degrees farther north. Fluorine analysis suggests a long period of accumulation. The following 10 mammalian species are recorded from Tennessee for the first time. Sorex arcticus, Microsorex hoyi, Citellus tridecemlineatus, Clethrionomys gapperi, Microtus pennsylvanicus, Synaptomys cooperi, Synaptomys borealis, Zapus nudsonius, Napaeozapus insignis, Martes americana. Six additional species are present as boreal relicts in the Great Smoky Mountains of eastern Tennessee but not at the site today : Sorex cinereus, Sorex dispar, Sorex palustris, Parascalops breweri, Glaucomys sabrinus, Mustela nivalis. Six forms are extinct: Canis dirus, Ursus americanus amplidens, Sangamona furtiva, Dasypus bellus, Mammut americanus,Megalonyx jeffersoni. Twenty-six additional species of mammals, all of the snails, birds, reptiles, and amphibians recovered from the fauna still inhabit the area today: The fauna is indicative of a cold-temperate climatic episode associated with the Wisconsin glaciation, but may be chronologically mixed. 


  PV article infos

Published in Vol. 02, Fasc. 2 (1969)

PDF

Page 7 of 19, showing 20 record(s) out of 365 total