Print ISSN: 0031-0247
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stratigraphy and biochronology of Oligo-Miocene of Kazakhstan
Eocene otoliths (Clinchfield Formation), Georgia
Fossil snakes, Palaeocene, Itaborai, Brazil, Part I
Notidanodon tooth (Neoselachii: Hexanchiformes) in the Late Jurassic of New Zealand
Abstract book of the 18th Conference of the EAVP
Eocene (57) , Quercy Phosphorites (38) , Systematics (32) , Rodents (29) , Mammalia (27)
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Cryptomerix Schlosser, 1886, Tragulidé de l'oligocène d'Europe ; relations du genre et considérations sur l'origine des ruminants.Jean SudreKeywords: Archaic Ruminants; Paleobiogeography; Quercy Phosphorites; Systematics; TragulidsAbstract The genus Cryptomeryx SCHLOSSER, 1886, inusited during a long period, has been discovered in Lower and Middle Oligocene localities of the Quercy region (South-West France). This new material, as well as specimens from the old collections referred to Cryptomeryx, are described; their study, allows us precising the definition of the genus, and confirming its allocation to the Tragulidae family. The type species of the genus, Crypmmeryx gaudryi (= Lophiomeryx gaudryi FILHOL, 1877), occurs in several localities at the base of the Middle Oligocene (Itardies, La Plante 2, Roqueprune 2, Soulce, Herrlingen 1). The new species C. matsoui n. sp. has been defined in the older locality of Mas de Got (top of Lower Oligocene). It is possible that the species Pseudamphimeryx decedens STEHLIN, 1910 pertains to the same genus. Also to the Tragulids must be referred the monospecific genus Iberomeryx (I. parvus GABOUNIA, 1964) from Upper Oligocene of Benara (Georgie, URSS), with which Cryptomeryx is related. These genera are not direct ancestors of Miocene tragulids; their occurrence in the Western European Oligocene results from a first immigration wawe of the family. These Tragulids are one of the most archaic groups of Ruminants. They are probably derived from a primitive stock which had acquired in Asia the selenodont condition of the dentition. Article infos Published in Vol. 14, Fasc. 1 (1984) |
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Les rongeurs de l'Eocène d'Afrique Nord-Occidentale [Glib Zegdou ( Algérie) et Chambi (Tunisie)] et l'origine des anomaluridae.Monique Vianey-Liaud, Jean-Jacques Jaeger, Jean-Louis Hartenberger and Mahammed MahboubiKeywords: Africa; Eocene; New taxa; Paleobiogeography; PHYLOGENY; RodentsAbstract This paper is about the oldest African rodents faunas, from the late Early Eocene, or early Middle Eocene, Glib Zegdou (Algeria) and Chambi (Tunisia) localities. Five species are described and figured, belonging to a new family here created, the Zegdoumyidae. Article infos Published in Vol. 23, Fasc. 1-4 (1994) |
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Revision of the family Cephalomyidae (Rodentia, Caviomorpha) and new cephalomyids from the early Miocene of Patagonia.Alejandro KramarzKeywords: Cephalomyidae; Lower Miocene; Patagonia; Rodentia; Soriamys; SystematicsAbstract A new genus of hystricognath rodent with two new species, Soriamys gaimanensis and Soriamys ganganensis, from the Colhuehuapian Age (Early Miocene), Sarmiento Formation, of Patagonia is described. The first species comes from the south barranca of the valley of Rio Chubut, near Gaiman locality (Chubut Province). It is known through a great number of dental remains in different stages of wear. The teeth are protohypsodont, with cement in the principal valleys. P4 are simpler, more oval inoutline and without a differentiated hypocone-hypoflexus. Upper molars are pentalophodont in early stages of wear and become bilobated in middle and advanced stages; M3 have a temporary third posterior lobe due to the maintenance of the braquiflexus on the posterior wall of the tooth. Lower teeth have a completely asymrnetrical pattern in relation to the uppers. The molars are trilophodont, with only one complex crest in the trigonid composed of the fusion of the anterolophid and mesolophid. The dp4 have a derived pentalophodont pattern due to the loss or fusion of the mesolophid and the development of an accessory transverse crest between the anterolophid and metalophid. The second species is known through a complete skull and jaw and other skull fragments with the dentition, proceeding from Pampa de Gan Gan, Chubut province. Respect to the first species, the teeth are higher crowned, with an earlier occlusal simplification and a third posterior lobe of M3 more developed and persistent. The skull and jaws show many chinchilloid characters, such as jugal bone with an ascending process, concave palate, very prominent dorsal shelf of the masseteric fossa, nasolachrymal duct opened laterally on the maxillary and very developed lateral mandibular fossa. Moreover, Soriamys is closely related to Cephalomys by sharing a similar asymmetric dental pattern and other dental and mandibular characters. These two genera constitute a natural group, the Cephalomyidae, with peculiar dental characters, like the asymmetric pattem of the upper and lower teeth; Cephalomyopsis, and probably Litadontomys, can be considered part of this group. Scotamys and Perimys constitute a distinct lineage (the Neopiblemidae or Perimyidae), more closely related to the chinchillids. Many characters shared by cephalomyids, eocardiids and caviids suggest a closer affinity between the Chinchilloidea and the Cavioiidea as a whole. Abrocoma shows also an asymmetric dental pattern and other chinchilloid features that suggest some degree of relationship with the cephalomyids, still not well determined. Article infos Published in Vol. 30, Fasc. 1-2 (2001) |
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Systematic and evolutionary relationships of the hipparionine horses from Maragheh, Iran (Late Miocene, Turolian age)Raymond L. BernorKeywords: evolution; Hipparionine horses; Iran; Systematics; TurolianAbstract A systematic analysis of an hipparionine horse assemblage from Maragheh, Iran is made. A brief orientation to systematic philosophy and informal superspecific characterizations of some Old World hipparionines is given as a background to this work. A character state analysis of skulls is made, and has revealed five distinct species. A character state and stratigraphic trend analysis of isolated check tooth and postcranial remains, with known provenance, is also made. These two combined analyses reveal that the most resolute discrimination of hipparionine species and their evolutionary relationships occurs when multiple character complexes of associated skulls, maxillary and mandibular dentitions are made. When this is not possible, skulls have provided the best basis for discriminating species and their evolutionary relationships. Traditional characters of isolated cheek teeth and postcranial remains are shown here to offer limited information content for hipparionine phylogenetic systematics. The systematic portion of this study includes a comprehensive description of cranial and postcranial remains, and has further corroborated the distinction of five species which belong to at least three superspecific groups including: «Hipparion» geltyi sp. nov., Group 1; Hipparion prostylum (s. l.), and Hipparion campbelli sp. nov., Group 3; «Hipparíon» aff. moldavicum and «Hipparion» ?matthewi, Group 2. These species stratigraphic ranges and evolutionary relationships are also given here and argued to be important for establishing future hipparionine geochronologic correlations between a number of Eurasian late Miocene provinces. Article infos Published in Vol. 15, Fasc. 4 (1985) |
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La poche à phosphate de Ste-Neboule (Lot) et sa faune de vertébres du Ludien Supérieur. 1 La poche et son remplissageBernard GèzeKeywords: Eocene; Quercy PhosphoritesAbstract La poche de Ste-Néboule, commune de Béduer (Lot), 15 km environ à l'WSW de Figeac, fait partie du groupe le plus septentrional des gouffres creusés par les ruissellements du Paléogène dans les calcaires jurassiques de la bordure sud-ouest du Massif Central et qui furent comblés à la même époque par des argiles sidérolithiques accompagnées de phosphate de chaux concrétionné ainsi que des restes de la célèbre faune dite «des phosphorites du Quercy» . Article infos Published in Vol. 08, Fasc. 2-4 (1978) |
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The new Algerian locality of Bir el Ater 3: validity of Libycosaurus algeriensis (Mammalia, Hippopotamoidea) and the age of the Nementcha FormationFabrice Lihoreau, Lionel Hautier and Mahammed MahboubiKeywords: Dispersal event; Miocene; North Africa; Tetralophodondoi: 10.18563/pv.39.2.e1 Abstract The description of original material of anthracothere and proboscidean in the new locality of Bir el Ater 3 from East Algeria, and a thorough review of early Libycosaurus remains of Bir el Ater 2 allows us validating L. algeriensis as the smallest and earliest species of Libycosaurus and probably the earliest migrant of the genus from Asia. The presence of a Tetralophodon in the Neogene Nementcha formation might represent the earliest occurrence of the genus in Africa. These original fossil remains allow us to discuss the age of the Neogene part of the Nementcha formation close to the Serravalian/Tortonian boundary. Article infos Published in Vol.39-2 (2015) |
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Nouvelles données sur les mammifères du Thanétien et de l'Yprésien du bassin d'Ouarzazate (Maroc) et leur contexte stratigraphique.Emmanuel Gheerbrant, Jean Sudre, Sevket Sen, Claude Abrial, Bernard Marandat, Bernard Sigé and Monique Vianey-LiaudKeywords: early Paleogene; magnetostratigraphy; Mammals; Morocco; North Africa; Ouarzazatz basin; SystematicsAbstract New faunal and stratigraphical data on the vertebrates localities from the early Paleogene of the Ouarzazate Basin (Adrar Mgorn 1, Adrar Mgorn 1 bis et N'Tagourt 2), Morocco, are presented. A magnetostratigraphical study, the first for such early Paleogene Arabo-African mammal localities, and the discovery of probable remains of the nannofossil Discoaster support the Thanetian age of the Adrar Mgorn 1 site. The magnetostratigraphy suggests a slightly later age than was thought for the Paleogene formations of the local series of Tinerhir and for the vertebrate localities: late or latest Thanetian for Adrar Mgorn 1 and Adrar Mgorn 1 bis, middle Ypresian for N'Tagourt 2. It also indicates a lower position of the KT boundary in the series. Two tons of matrix recovered in the vertebrate sites have vielded new data on the micromammals. A damaged lower molar from N'Tagourt 2 is referable to Khamsaconus bulbosus and supports the proboscidean affinities of this species and especially possible relationships with bunolophodont taxa such as elephantiforms. A lower molar from Adrar Mgorn 1 bis belongs to a new form which can be identified as a plesiadapiform or an euprimate close to Altiatlasius koulchii though significantly larger. A new material from Adrar Mgorn 1 illustrates a new dilambdodont adapisoriculid species which is referable to Garatherium : ?Garatherium todrae n. sp. Another species referred to Garatherium is known in the locality (?Garatherium n. sp.). Garatherium is a new lineage from the Ouarzazate basin which crosses the Paleocene-Eocene boundary together with Palaeoryctes, Didelphodontinae gen. and sp. 2, Todralestes, and Afrodon, and it is the first Paleocene-Eocene lineage identified outside of this basin (Garatheríum is based on a species from El Kohol, Algeria). Among the Paleocene-Eocene lineages from the Ouarzazate basin, it should be also mentioned a new possible carnassial form (carnivoran or creodont; Adrar Mgorn 1), and an upper molar of Cimolestes cf. incisus (Adrar Mgorn 1 bis). The upper molar THR 168 previously reported as from an indeterminate didelphodontine is here identified as the M1/ of Afrodon chleuhi. The micromammal faunas from the Ouarzazate basin are positioned in the global chronological framework of the mammal localities from the Paleogene of the Arabo-African domain. Article infos Published in Vol. 27, Fasc. 3-4 (1998) |
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La poche à phosphate de Ste-Néboule (Lot) et sa faune de vertebres du Ludien supérieur. 7- Didelphides (Marsupiaux)Jean-Yves CrochetKeywords: Eocene; Quercy PhosphoritesAbstract The family Didelphidae is represented by three species in the Sainte-Néboule site, phosphorites of Quercy (lower Oligocene, San Cugat's nivel): Amphiperatherium minutum (Aymard), Amphiperatherium sp. and Peratherium cuvieri (Fischer). Only the first and third species are abundant (88 and 97 pieces). This two populations are described. The marsupial fauna of the european lower Oligocene is not recognized in its entirety in this site. Article infos Published in Vol. 08, Fasc. 2-4 (1978) |
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Neolicaphrium recens Frenguelli,1921,the only surviving proterotheriidae (Litopterna, Mammalia) into the south american Pleistocene.Mariano Bond, Daniel Perea, Martin Ubilla and Adan TauberKeywords: Litopterna; Neolicaphrium recens; Pleistocene; Proterotheriidae; South AmericaAbstract The litoptem Proterotheriidae are extinct endemic South American ungulates frequently used as an example of evolutionary convergence with the horses. They were considered to be exclusively Tertiary representatives with the youngest record being in the late Pliocene, before the appearence of the equids and cervids during the Great American Interchange. Two undoubted Pleistocene records in Argentina and the specimen here described from Uruguay, confirm the persistence of the proterotherids into that period. In the Quaternary, these ungulates are found outside the typical pampean region and probably were confined to a few northern and warmer more forested relictual microhabitats. Article infos Published in Vol. 30, Fasc. 1-2 (2001) |
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La Poche à phosphate de Ste-Neboule (Lot) et sa faune de vertébres du Ludien Supérieur. 3- ChéloniensFrance de BroinKeywords: Eocene; Quercy PhosphoritesAbstract The few remains recently collected at Ste Néboule (upper Eocene) belong to three genera: the Testudinid Ergilemys, of which it is the oldest occurence in Western Europa, probably Palaeochelys and an unpublished genus, which is peculiar to the Phosphorites du Quercy. Some statements are made on the chelonian fauna as a whole in that région. After the study of some characters proper to the genus Ergilemys, some remarks are made concerning its antecedents and descendants. Article infos Published in Vol. 08, Fasc. 2-4 (1978) |
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Analysis of mammalian communities from the late Eocene and Oligocene of southern FranceSerge LegendreKeywords: Late Eocene; Mammalian communities; Oligocene; Quercy; Southern FranceAbstract Valverde's cenogram method is used to analyse mammalian communities from the late Eocene to late Oligocene of southern France, mainly from the "Phosphorites du Quercy". Cenogram analysis involves plotting the size of each component species in a fauna on a semilog diagram in rank order, permitting fossil faunas to be compared with Recent ones. The configurations of Recent communities serve as models for establishing the general environmental characteristics of fossil mammalian faunas. This method of analysis applied to faunal sequence can reveal major and sudden ecological perturbations. The paleobiogeographical event (i.e. the mammalian immigration wave) at the Eocene-Oligocene Boundary in western Europe, known as the «Grande Coupure", is here shown to represent a drastic and sudden ecological change: late Eocene tropical environments in Europe deteriorated rapidly turning to subdesert or desert environments al the beginning of the Oligoccne. Article infos Published in Vol. 16, Fasc. 4 (1986) |
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New datation of the Tafna Basin (Algeria): A combination between biochronological and magnetostratigraphical dataSalamet Mahboubi, Mouloud Benammi and Jean-Jacques JaegerKeywords: correlations; Late Miocene; North Africa; Rodentiadoi: 10.18563/pv.39.1.e1 Abstract The Tafna Basin corresponds to the lowlands, which are located in front of Tessala and Traras ranges, below the Tlemcen mountains, Algeria. This basin displays a complete sedimentary cycle dominated by lagoonal-fluvial and marine deposits. The continental formations located at the base of these deposits are mainly composed of alternating sandstones and clays. An early late Miocene age has been previously attributed to them, based on direct correlations with marine deposits. Search for micromammal fossils led to the discovery of three different rodent species from a single level of the Djebel Guetaf section, located at the bottom of these deposits. The rodent assemblage indicates a late Miocene age. Combined magnetostratigraphical and biostratigraphical investigations were carried out to provide a more accurate age control of these continental deposits. Sixty-four oriented rock samples were collected for a magnetostratigraphic study along a 92 meters thick section including the fossiliferous layer. Rock magnetic investigations indicate the presence of both high and low coercivity minerals. Specimens subjected to progressive thermal demagnetization procedures show that the samples exhibit a high temperature magnetization component and display a normal polarity. Based on biostratigraphic constraints, the Guetaf section is correlated with Chron C4An, indicating an age ranging from Article infos Published in Vol.39-1 (2015) |
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Comparative bone histology of rhabdodontid dinosaursEdina ProndvaiKeywords: bone histology-based ontogeny; Mochlodon; Rhabdodon; skeletal maturation; Zalmoxesdoi: 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. Article infos Published in Vol.38-2 (2014) |
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The evolution of the molar pattern of the Erethizontidae (Rodentia,Hystricognathi) and the validity of Parasteiromys Ameghino, 1904.Adriana M. CandelaKeywords: Argentina; Erethizontidae; Hystricognathi; Miocene; Molar evolution; Porcupines; Rodentia; SystematicsAbstract The genus Parasteiromys AMEGHINO, 1904 is revalidated, and P. friantae sp. nov. (Hystricognathi, Erethizontidae) from Colhuehuapian (early Miocene) sediments of the southern cliff of Colhue-Huapi Lake (Province of Chubut, Argentina), is described. The molar morphology of these taxa and of living porcupines adds new elements to understand the dental evolution of the Erethizontidae, and to propose the hypothetical ancestral molar pattern for this family. This pattern does not correspond to any of the morphologies traditionally proposed as ancestral for South American hystricognathous rodents. The proposed pattern is characterized by a metaloph disconnected from the posteroloph and oriented towards the hypocone, and the third loph incompletely developed with the lingual portion homologous to the mesolophule of Baluchimyinae (Chapattimyidae) from the Miocene of Pakistan. The inferred steps of the molar evolution of erethizontids towards the pentalophodont condition, considered derived for the family, are illustrated. This study strengthens the hypothesis placing erethizontids in a basal position among rodents of the suborder Hystricognathi. Article infos Published in Vol. 28, Fasc. 1 (1999) |
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Preliminary evolution of paleosols and implications for interpreting vertebrate fossil assemblages, Kuldana formation, Northern PakistanAndres Aslan and J. G. M. ThewissenKeywords: Eocene; Kuldana Formation; Pakistan; Paleosols; Pedogenic Carbonate; taphonomy; Time Averaging; Vertebrate FossilsAbstract Paleosols and the taphonomy of vertebrate fossils in the Eocene Kuldana Formation of northern Pakistan provide important information on the preservation and time-averaging of fossil assemblages. Morphologic, mineralogic, and chemical data as well as comparisons with Quaternary soils suggest that Kuldana paleosols formed under generally dry and oxidizing conditions over time intervals of less than 100 000 years and perhaps as short as 1000 years. The distribution of carbonate in Kuldana paleosols further indicates that the upper half of the profiles were acidic whereas the lower halves were alkaline. Vertebrate fossils are rare in Kuldana paleosols and occur primarily in well-cemented sandstones and conglomerates with abundant micritic and iron-stained nodules that were reworked from floodplain soils. The scarcity of vertebrate remains in Kuldana paleosols probably reflects a combination of acidic, dry, and oxidizing conditions in the upper half of the profiles and rapid floodplain sedimentation. Comparisons between the taphonomic characteristics of Kuldana channel fossil assemblages and bone accumulations in modem rivers provide a basis for estimating the length of time represented by Kuldana fossils from several important localities. Vertebrate fossil assemblages from Barbora Banda are characterized by a low-diversity paleofauna, partially articulated skeletons, and bones that are sorted by size and shape. Comparison with bone accumulations in modern rivers suggests that the fossils from Barbora Banda accumulated in 1 to 10 years. Vertebrate fossils from the Lower Kuldana in the Kala Chitta Hills region, typified by locality H-GSP 62, are characterized by a high-diversity paleofauna and generally random and unsorted fossil bone distributions, which suggest that the fossils from these localities represent longer time intervals than the Barbora Banda fossils. Based on the time estimates for Kuldana paleosol development, fossil assemblages in Kuldana channel deposits in the Kala Chitta Hills region probably represent time intervals of about 1000 years. Article infos Published in Vol. 25, Fasc. 2-4 (1996) |
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An Australian Miocene Brachipposideros (Mammalia, Chiroptera) related to Miocene representatives from FranceBernard Sigé, Suzanne J. Hand and Michael ArcherKeywords: Australia; bats; Chiroptera; MioceneAbstract 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. Article infos Published in Vol. 12, Fasc. 5 (1982) |
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Les Périssodactyles (Mammalia) du gisement Bartonien supérieur de Robiac (Éocène moyen du Gard, Sud de la France)Jean-Albert RemyKeywords: Chasmotherium; new species; Palaeotheriidae; paleoenvironmentsdoi: 10.18563/pv.39.1.e3 Abstract We present here a new updated counting of the perissodactyls of Robiac, the type locality of the MP 16 level of the biochronological scale of paleogene mammals and that of the Robiacian stage of Eocene Land Mammals Ages in Western Europe. Article infos Published in Vol.39-1 (2015) |
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Contributions à l'étude du gisement Miocène supérieur de Montredon (Hérault). Les grands mammifères. 8 - Analyse paléoécologique de la faune mammalienneSerge LegendreKeywords: France; Mammalia; Montredon; Paleoecology; Upper MioceneAbstract The species diversity of the mammalian fauna from Montredon (Hérault, France, late Miocene) is examined in terms of richness and abundance. A cenogramic analysis of the fossil mammalian community suggests the prevalence of open habitats, with the presence of marshes and of a poorly developed galery forest, and a climate rather warm and dry. Article infos Published in Vol. 18, Ext (1988) |
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Description des rongeurs Pliocènes de la faune du Mont-Hélène (Pyrénées-Orientales, France), nouveau jalon entre les faunes de Perpignan (Serrat-d'en-Vacquer) et de Sète.Jean-Pierre Aguilar, Marc Calvet and Jacques MichauxKeywords: Chronology; Climatology; France; Mont-Hélène; Pliocene; RodentsAbstract The Mont-Hélène's fauna [Pyrénées-Orientales, France], includes 15 species of rodents with a new one, Occitanomys montheleni n. sp. among the 9 species of the Murids which are listed. The uncommon Cricetid, Blancomys neglectus, is well represented in the fauna. Peculiarities of the population referred to Slephanomys cf. donnezaniare discussed. The locality a fissure filling may be the oldest one of Tabianian age known in Southern France. The diversity of the Murids gives evidence of a subtropical climate and of a diversified environment which may be linked to the spreading of the coastal plain following the filling up of the Roussillon Neogene Basin. Article infos Published in Vol. 16, Fasc. 3 (1986) |
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Middle Eocene rodents from the Subathu group, Northwest Himalya.Kishor Kumar, Rahul Srivastava and Ashok SahniKeywords: Chapattimyidae; Eocene; evolution; India; Rodentia; Subathu group; SystematicsAbstract Extensive collecting in previously known and new Middle Eocene rodent localities in the Subathu Group of the Rajauri and Reasi districts, Jammu and Kashmir (northwest Himalaya, India) has yielded over 500 isolated cheek teeth, numerous incisors and cheek tooth fragments, and two mandibular fragments with M/1-M/3. An analysis of this additional material and a restudy of that reported earlier from the Metka (Rajauri) area has revealed the presence of diverse Middle Eocene ctenodactyloid rodents in India. The assemblage comprises six genera and twelve species, viz.., Bírbalomys woodi, B. ibrahimshahi, B. sondaari, Basalomys vandermeuleni, B. ijlsti, B. lavocati, Chapattimys wilsoni, C. debruijni, Gumbatomys asifi, cf. Advenimus bohlini, cf. Petrokoslovia sp. indet. 1 and cf. Petrokoslovia sp. indet. 2. Most species of this assemblage are endemic to the Indian subcontinent and are referred to the Family Chapattimyidae. However, at least three taxa, viz.., cf. Advenimus bohlini, cf. Petrokoslovia sp.indet. 1 and cf. Pezrokoslovia sp. indet. 2 show close affinities with their Central and Eastern Asiatic contemporaries and are attributed to the Family Yuomyidae. The dentitions of most of the Middle Eocene rodents from India are described here in better detail thus providing more precise characterization than was available earlier. The taxonomie status of Basalomys, formerly a subgenus of Birbalomys has been raised to that of a genus. Basalomys vandermeuleni is here designated as the type species of Basalomys in place of B. ijlsti. The rodent assemblage from the Subathu Group is specifically similar to that from the coeval Kuldana Formation of Pakistan. The absence of Birbalomys ibrahimshahi and cf. Advenimus bohlini in Pakistan is related to sampling bias. The identifications of the Early Eocene rodents from Barbara Banda, Pakistan have been reexamined and the familial assignments of some of the Early and Middle Eocene rodents from Central and Eastern Asia have been discussed and reviewed in the light of recent discovery of early rodents in Mongolia. Article infos Published in Vol. 26, Fasc. 1-4 (1997) |
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