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Dieter F Mertz - One of the best experts on this subject based on the ideXlab platform.
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a numerically calibrated reference level mp28 for the terrestrial mammal based biozonation of the european upper Oligocene
International Journal of Earth Sciences, 2007Co-Authors: Dieter F Mertz, Michael Wuttke, Paul R Renne, Clemens ModdenAbstract:The fauna of the Enspel (Westerwald) and the neighbouring Karlich (Neuwied basin) fossil deposits correspond to the Upper Oligocene Mammal Paleogene (MP) reference level 28 and 28–30, respectively. Basaltic flows and a trachyte tuff terminating and predating the fossil deposit sedimentation allow to numerically calibrate the MP reference levels by radioisotope dating. Laser fusion 40Ar/39Ar step heating on volcanic feldspars yield a time interval of 24.9–24.5 Ma for reference level MP28 at Enspel and a maximum age of 25.5 Ma for the time interval MP28–MP30 at Karlich. Interpolation between the time intervals determined for the Enspel reference level MP28 and the age of the global Oligocene/Miocene boundary of 24.0 ± 0.1 Ma taken from literature results in time intervals of 24.5–24.2 Ma and 24.2–23.9 Ma for the younger reference levels MP29 and MP30, respectively. These intervals of ≤ 0.4 m.y. for MP reference levels of the latest Oligocene are short relative to older Oligocene MP reference levels 21–27 between 34 and 25 Ma. Since subdivision into MP reference levels essentially is based on assemblages of mammal taxa and on evolutionary changes in tooth morphology of mammals short MP time intervals during the latest Oligocene indicate a rapid evolutionary change relative to the early Oligocene.
Pierreolivier Antoine - One of the best experts on this subject based on the ideXlab platform.
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Late Oligocene caviomorph rodents from Contamana, Peruvian Amazonia
Special papers in palaeontology, 2017Co-Authors: Myriam Boivin, Laurent Marivaux, Adriana Candela, Maeva Orliac, Francois Pujos, Rodolfo Salas-gismondi, Julia Tejada-lara, Pierreolivier AntoineAbstract:The Deseadan South American Land Mammal Age (late Early Oligocene – Late Oligocene) attests to a time of great diversification in the caviomorph rodent fossil record. Nevertheless, Deseadan rodent-bearing localities in Neotropical lowlands are few and poorly known. Here we describe the rodent assemblages from two Late Oligocene localities, near Contamana, Loreto, Peru. Seven taxa are new to science: Palaeosteiromys amazonensis gen. et sp. nov., Plesiosteiromys newelli gen. et sp. nov., Loretomys minutus gen. et sp. nov., Scleromys praecursor sp. nov, Ucayalimys crassidens gen. et sp. nov., Chambiramys sylvaticus gen. et sp. nov. and Chambiramys shipiborum gen. et sp. nov. These rodent faunas show that caviomorphs were relatively diverse in Peruvian Amazonia during the Late Oligocene, with the co-occurrence of at least three extant superfamilies: Erethizontoidea, Octodontoidea and Chinchilloidea. Additionally, they mark the earliest known occurrences of Scleromys, of a small erethizontid closely related to Microsteiromys and of an adelphomyine closely reminiscent of Ricardomys (all taxa previously restricted to Miocene localities thus far). They also document a form potentially related to Eosallamys (previously known from around the Eocene–Oligocene transition at Santa Rosa in Peruvian Amazonia). Finally, the geographical range of Adelphomyinae and of Deseadomys is widely expanded to the lower latitudes of South America for the Deseadan interval. The latter elements, in addition to the record of a very primitive species of Scleromys, suggest the absence of palaeogeographical and palaeoenvironmental barriers within the southern cone of South America before the Oligocene–Miocene transition.
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Anthropoid primates from the Oligocene of Pakistan (Bugti Hills): Data on early anthropoid evolution and biogeography
Proceedings of the National Academy of Sciences of the United States of America, 2005Co-Authors: Laurent Marivaux, Yaowalak Chaimanee, Jeanjacques Jaeger, Pierreolivier Antoine, Jeanyves Crochet, Syed Rafiqul Hassan Baqri, Mouloud Benammi, Dario De Franceschi, Nayyer Iqbal, Grégoire MétaisAbstract:Asian tarsiid and sivaladapid primates maintained relictual distributions in southern Asia long after the extirpation of their close Holarctic relatives near the Eocene–Oligocene boundary. We report here the discovery of amphipithecid and eosimiid primates from Oligocene coastal deposits in Pakistan that demonstrate that stem anthropoids also survived in southern Asia beyond the climatic deterioration that characterized the Eocene–Oligocene transition. These fossils provide data on temporal and paleobiogeographic aspects of early anthropoid evolution and significantly expand the record of stem anthropoid evolution in the Paleogene of South Asia.
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early rhinocerotids mammalia perissodactyla from south asia and a review of the holarctic paleogene rhinocerotid record
Canadian Journal of Earth Sciences, 2003Co-Authors: Pierreolivier Antoine, Yaowalak Chaimanee, Jeanjacques Jaeger, Stephane Ducrocq, Laurent Marivaux, Jeanyves Crochet, Jeanloup WelcommeAbstract:The earliest rhinocerotids from South Asia are identified on the basis of few dental remains originating from the Late Eocene of Thailand (Wai Lek mine, Krabi Basin) and the Early Oligocene of Pakistan (Paali nala C2, Bugti Hills). Once synthesized, the Holarctic Paleogene rhinocerotid record points out a westward diachronism of rhinocerotid First Appearance Data, from North America to Europe via Asia, throughout mid-Cenozoic times. The faunal similarity among mammal localities from the Late Eocene and Early Oligocene of peninsular Thailand, southern China, and Pakistan suggests the existence of a single South Asian paleoprovince during this interval and the persistence of a tropical-subtropical climate. Substantial faunal changes recorded in eastern Balochistan reveal a significant climatic deterioration from the middle part of the Oligocene. Neither provinciality nor endemism is noticeable for rhinocerotoid taxa recognized in the Oligocene of the Indian subcontinent: neither the Himalayas nor the Tibet Plateau was a paleogeographic barrier for large mammals during this interval. Resume : Les plus anciens rhinocerotides d'Asie du Sud sont identifies grâce a quelques restes dentaires provenant de l'Eocene superieur de Thailande (Mine de Wai Lek, Bassin de Krabi) et de l'Oligocene inferieur du Pakistan (Paali nala C2, Collines Bugti). La synthese du registre fossile paleogene holarctique des rhinocerotides revele un net diachronisme des premieres apparitions de rhinocerotides depuis l'est (Amerique du Nord) vers l'ouest (Asie, puis Europe) au cours du Cenozoique moyen. La similarite des communautes de mammiferes entre les localites de l'Eocene superieur et de l'Oligocene inferieur de Thailande peninsulaire, de Chine du Sud et du Pakistan, suggere l'existence d'une seule Paleoprovince sud-asiatique pendant la periode consideree, sous un climat tropical a subtropical. Les changements fauniques enregistres au Balouchistan oriental revelent une deterioration climatique significative a partir du milieu de l'Oligocene. Aucun indice de provincialisme ou d'endemisme n'est releve pour les rhinocerotoides Oligocenes du Sous-continent indien : ni les Himalayas ni le Plateau du Tibet ne constituaient a l'epoque une barriere paleogeographique pour les grands mammiferes.
Clemens Modden - One of the best experts on this subject based on the ideXlab platform.
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a numerically calibrated reference level mp28 for the terrestrial mammal based biozonation of the european upper Oligocene
International Journal of Earth Sciences, 2007Co-Authors: Dieter F Mertz, Michael Wuttke, Paul R Renne, Clemens ModdenAbstract:The fauna of the Enspel (Westerwald) and the neighbouring Karlich (Neuwied basin) fossil deposits correspond to the Upper Oligocene Mammal Paleogene (MP) reference level 28 and 28–30, respectively. Basaltic flows and a trachyte tuff terminating and predating the fossil deposit sedimentation allow to numerically calibrate the MP reference levels by radioisotope dating. Laser fusion 40Ar/39Ar step heating on volcanic feldspars yield a time interval of 24.9–24.5 Ma for reference level MP28 at Enspel and a maximum age of 25.5 Ma for the time interval MP28–MP30 at Karlich. Interpolation between the time intervals determined for the Enspel reference level MP28 and the age of the global Oligocene/Miocene boundary of 24.0 ± 0.1 Ma taken from literature results in time intervals of 24.5–24.2 Ma and 24.2–23.9 Ma for the younger reference levels MP29 and MP30, respectively. These intervals of ≤ 0.4 m.y. for MP reference levels of the latest Oligocene are short relative to older Oligocene MP reference levels 21–27 between 34 and 25 Ma. Since subdivision into MP reference levels essentially is based on assemblages of mammal taxa and on evolutionary changes in tooth morphology of mammals short MP time intervals during the latest Oligocene indicate a rapid evolutionary change relative to the early Oligocene.
Laurent Marivaux - One of the best experts on this subject based on the ideXlab platform.
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The rodents from Santpedor-2 (Ebro Basin, NE Spain) confirm the Oligocene age of the latest primates from the Paleogene of Europe
Geobios, 2019Co-Authors: Monique Vianey-liaud, Raef Minwer-barakat, Laurent MarivauxAbstract:This paper provides a revised and updated description and identification of the rodents from Santpedor-2 (northeastern Spain). The age of this locality is particularly relevant, because it is one of the few European sites assigned to the early Oligocene that has yielded primate remains. However, the rodent assemblage from this site has never been described in detail, and therefore the Oligocene age of this locality remained tentative. Despite the scarcity of the material, the rodents from Santpedor-2 are characteristic enough either to be identified as already known species, or at least compared with close species. Eight different rodent taxa were recognized. Among them, the theridomyid Ectropomys exiguus, which is recorded only in late Eocene localities, and the glirid Glamys devoogdi, which is known in both latest Eocene and early Oligocene localities. The other taxa are found only in Oligocene localities, and consist of the theridomyid Paratheridomys margaritae and members of two families that arrived in Europe at the beginning of the Oligocene: eomyids (Eomys sp.) and cricetids (Eucricetodon atavus, cf. Heterocricetodon sp., cf. Pseudocricetodon sp.). Finally, another theridomyid (Issiodoromyinae) seems to correspond to a new species and new genus, the main features of which correspond to early Oligocene evolutionary grades. This rodent assemblage from Santpedor-2 is assigned to the early Oligocene, mainly on the basis of the presence of immigrant rodents that reached Europe in relation with the Grande Coupure (cricetids and eomyids). This dating is notably supported by the presence of P. margaritae together with Glamys devoogdi, both being found in Hoogbutsel (early Rupelian, MP21). Only one rodent (E. exiguus) represents an Eocene relict, as is the case of Pseudoloris, the only primate recorded in this locality. Therefore, this study supports the Oligocene age of Santpedor-2 and then the persistence of omomyid primates in the Iberian Peninsula (at least locally) after the Grande Coupure.
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Late Oligocene caviomorph rodents from Contamana, Peruvian Amazonia
Special papers in palaeontology, 2017Co-Authors: Myriam Boivin, Laurent Marivaux, Adriana Candela, Maeva Orliac, Francois Pujos, Rodolfo Salas-gismondi, Julia Tejada-lara, Pierreolivier AntoineAbstract:The Deseadan South American Land Mammal Age (late Early Oligocene – Late Oligocene) attests to a time of great diversification in the caviomorph rodent fossil record. Nevertheless, Deseadan rodent-bearing localities in Neotropical lowlands are few and poorly known. Here we describe the rodent assemblages from two Late Oligocene localities, near Contamana, Loreto, Peru. Seven taxa are new to science: Palaeosteiromys amazonensis gen. et sp. nov., Plesiosteiromys newelli gen. et sp. nov., Loretomys minutus gen. et sp. nov., Scleromys praecursor sp. nov, Ucayalimys crassidens gen. et sp. nov., Chambiramys sylvaticus gen. et sp. nov. and Chambiramys shipiborum gen. et sp. nov. These rodent faunas show that caviomorphs were relatively diverse in Peruvian Amazonia during the Late Oligocene, with the co-occurrence of at least three extant superfamilies: Erethizontoidea, Octodontoidea and Chinchilloidea. Additionally, they mark the earliest known occurrences of Scleromys, of a small erethizontid closely related to Microsteiromys and of an adelphomyine closely reminiscent of Ricardomys (all taxa previously restricted to Miocene localities thus far). They also document a form potentially related to Eosallamys (previously known from around the Eocene–Oligocene transition at Santa Rosa in Peruvian Amazonia). Finally, the geographical range of Adelphomyinae and of Deseadomys is widely expanded to the lower latitudes of South America for the Deseadan interval. The latter elements, in addition to the record of a very primitive species of Scleromys, suggest the absence of palaeogeographical and palaeoenvironmental barriers within the southern cone of South America before the Oligocene–Miocene transition.
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Rodent paleocommunities from the Oligocene of Ulantatal (Inner Mongolia, China)
Palaeovertebrata, 2014Co-Authors: Helder Gomes Rodrigues, Laurent Marivaux, Monique Vianey-liaudAbstract:The Oligocene deposits of the Ulantatal area in Inner Mongolia (China) contain among the richest mammalian faunas from Asia. To date, only some parts of the rodent faunas have been described. Here, we propose to review the rodent faunal lists for each site, including the description of a few new rodent specimens. We describe three additional rodent species: the Cylindrodontidae Anomoemys lohiculus, the Eomyidae Asianeomys sp., and the Dipodidae Litodonomys huangheensis. This study allows us to constrain the stratigraphic range of Anomoemys lohiculus, which ranged from the late Early Oligocene to the early Late Oligocene in this area. Asianeomys sp. and Litodonomys huangheensis are dated from the latest Oligocene. These Oligocene deposits consist now of more than 70 species of mammals if we include the fauna from Kekeamu. This latter corresponds to the basal part of the Ulantatal Formation and could be dated biochronologically from the earliest Oligocene. When compared to the faunas from the Valley of Lakes in Central Mongolia, the Ulantatal faunas present a great majority of rodents, and this difference can be partly explained by sampling and description biases regarding macro-mammals. This study also shows that variations existed between Inner and Central Mongolia, especially regarding the composition of the rodent paleocommunities. However, the assessment of their evolutionary history in this part of Asia with respect to the important climate and environment changes, require further precisions and more material than current data allow.
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Anthropoid primates from the Oligocene of Pakistan (Bugti Hills): Data on early anthropoid evolution and biogeography
Proceedings of the National Academy of Sciences of the United States of America, 2005Co-Authors: Laurent Marivaux, Yaowalak Chaimanee, Jeanjacques Jaeger, Pierreolivier Antoine, Jeanyves Crochet, Syed Rafiqul Hassan Baqri, Mouloud Benammi, Dario De Franceschi, Nayyer Iqbal, Grégoire MétaisAbstract:Asian tarsiid and sivaladapid primates maintained relictual distributions in southern Asia long after the extirpation of their close Holarctic relatives near the Eocene–Oligocene boundary. We report here the discovery of amphipithecid and eosimiid primates from Oligocene coastal deposits in Pakistan that demonstrate that stem anthropoids also survived in southern Asia beyond the climatic deterioration that characterized the Eocene–Oligocene transition. These fossils provide data on temporal and paleobiogeographic aspects of early anthropoid evolution and significantly expand the record of stem anthropoid evolution in the Paleogene of South Asia.
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early rhinocerotids mammalia perissodactyla from south asia and a review of the holarctic paleogene rhinocerotid record
Canadian Journal of Earth Sciences, 2003Co-Authors: Pierreolivier Antoine, Yaowalak Chaimanee, Jeanjacques Jaeger, Stephane Ducrocq, Laurent Marivaux, Jeanyves Crochet, Jeanloup WelcommeAbstract:The earliest rhinocerotids from South Asia are identified on the basis of few dental remains originating from the Late Eocene of Thailand (Wai Lek mine, Krabi Basin) and the Early Oligocene of Pakistan (Paali nala C2, Bugti Hills). Once synthesized, the Holarctic Paleogene rhinocerotid record points out a westward diachronism of rhinocerotid First Appearance Data, from North America to Europe via Asia, throughout mid-Cenozoic times. The faunal similarity among mammal localities from the Late Eocene and Early Oligocene of peninsular Thailand, southern China, and Pakistan suggests the existence of a single South Asian paleoprovince during this interval and the persistence of a tropical-subtropical climate. Substantial faunal changes recorded in eastern Balochistan reveal a significant climatic deterioration from the middle part of the Oligocene. Neither provinciality nor endemism is noticeable for rhinocerotoid taxa recognized in the Oligocene of the Indian subcontinent: neither the Himalayas nor the Tibet Plateau was a paleogeographic barrier for large mammals during this interval. Resume : Les plus anciens rhinocerotides d'Asie du Sud sont identifies grâce a quelques restes dentaires provenant de l'Eocene superieur de Thailande (Mine de Wai Lek, Bassin de Krabi) et de l'Oligocene inferieur du Pakistan (Paali nala C2, Collines Bugti). La synthese du registre fossile paleogene holarctique des rhinocerotides revele un net diachronisme des premieres apparitions de rhinocerotides depuis l'est (Amerique du Nord) vers l'ouest (Asie, puis Europe) au cours du Cenozoique moyen. La similarite des communautes de mammiferes entre les localites de l'Eocene superieur et de l'Oligocene inferieur de Thailande peninsulaire, de Chine du Sud et du Pakistan, suggere l'existence d'une seule Paleoprovince sud-asiatique pendant la periode consideree, sous un climat tropical a subtropical. Les changements fauniques enregistres au Balouchistan oriental revelent une deterioration climatique significative a partir du milieu de l'Oligocene. Aucun indice de provincialisme ou d'endemisme n'est releve pour les rhinocerotoides Oligocenes du Sous-continent indien : ni les Himalayas ni le Plateau du Tibet ne constituaient a l'epoque une barriere paleogeographique pour les grands mammiferes.
Paul R Renne - One of the best experts on this subject based on the ideXlab platform.
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a numerically calibrated reference level mp28 for the terrestrial mammal based biozonation of the european upper Oligocene
International Journal of Earth Sciences, 2007Co-Authors: Dieter F Mertz, Michael Wuttke, Paul R Renne, Clemens ModdenAbstract:The fauna of the Enspel (Westerwald) and the neighbouring Karlich (Neuwied basin) fossil deposits correspond to the Upper Oligocene Mammal Paleogene (MP) reference level 28 and 28–30, respectively. Basaltic flows and a trachyte tuff terminating and predating the fossil deposit sedimentation allow to numerically calibrate the MP reference levels by radioisotope dating. Laser fusion 40Ar/39Ar step heating on volcanic feldspars yield a time interval of 24.9–24.5 Ma for reference level MP28 at Enspel and a maximum age of 25.5 Ma for the time interval MP28–MP30 at Karlich. Interpolation between the time intervals determined for the Enspel reference level MP28 and the age of the global Oligocene/Miocene boundary of 24.0 ± 0.1 Ma taken from literature results in time intervals of 24.5–24.2 Ma and 24.2–23.9 Ma for the younger reference levels MP29 and MP30, respectively. These intervals of ≤ 0.4 m.y. for MP reference levels of the latest Oligocene are short relative to older Oligocene MP reference levels 21–27 between 34 and 25 Ma. Since subdivision into MP reference levels essentially is based on assemblages of mammal taxa and on evolutionary changes in tooth morphology of mammals short MP time intervals during the latest Oligocene indicate a rapid evolutionary change relative to the early Oligocene.
