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Mebrouk F.,Oran University of Science and Technology - Mohamed Boudiaf | Mebrouk F.,Jijel University | Colin J.-P.,Impasse des Biroulayres | Colin J.-P.,University of Lisbon | Hennache F.,Oran University of Science and Technology - Mohamed Boudiaf
Carnets de Geologie | Year: 2011

An outcrop with non-marine ostracods in the Early Eocene of Djebel Amour, an outcrop well dated by a rich charo-phyta microflora characterizing the Peckichara disermas Zone of the Early Eocene (Lower Ypresian = Ilerdian), has yielded an interesting non-marine ostracode fauna in the Djebel Amour, Western Saha-rian Atlas, in Algeria. This fauna is characterized by the dominance of the genus Neocyprideis with the new species Neocyprideis meguerchiensis nov. sp., and the occasional occurrence of the genera Hemi-cyprideis, Perissocytheridea (P. algeriensis nov. sp.) and Limnocythere. It is the second discovery of the genus Neocyprideis in the Palaeogene of the African continent, the first one being in the Early Eoce-ne of Senegal. The Neocyprideis are represented by 75% of smooth and normally calcified carapaces, 20% by reticulate-noded specimens and 5% of only reticulate forms. This polymorphism suggests a marked seasonality with fluctuating salinity. The dominance of smooth and well calcified morphs indi-cates an environment with an equilibrium Ca++/Mg++, the reticulate morphs characterizing waters richer in Mg++. The presence of noded-reticulate forms suggests seasonal influxes of organo-siliceous material from the continent and a salinity which could temporarily reach values lower or equal to 5 psu. Source


Colin J.-P.,Impasse des Biroulayres | Colin J.-P.,University of Lisbon | Neraudeau D.,CNRS Geosciences Laboratory of Rennes | Nel A.,CNRS Systematics, Biodiversity and Evolution Institute | Perrichot V.,CNRS Geosciences Laboratory of Rennes
Revue de Micropaleontologie | Year: 2011

This paper presents fossil faecal pellets - also named coprolites or frass - attributed to termites, which were found in amber and lignitic clay from the Wealden (Hauterivian-Barremian?), Late Albian and Early Cenomanian of south-western France. These coprolites have a characteristic subcylindrical shape and hexagonal transverse section and are assignable to Microcarpolithes hexagonalis Vangerow. The termite families that possibly produced these coprolites are discussed. The noticeable lack of termite attacks on the fossil wood associated with amber and lignitic clay is taphonomically analyzed in relation with the palaeoflora and palaeoclimate of these amber forests. The different medium where coprolites were found (amber, wood, sediments) suggests that primitive Cretaceous termites had already developed various biologies, such as wood or cryptic foraging, but probably not yet soil-feeding. © 2011 Elsevier Masson SAS. Source


Andreu B.,University Paul Sabatier | Colin J.-P.,Impasse des Biroulayres | Colin J.-P.,University of Lisbon | Singh J.,Oil and Natural Gas Corporation
Gondwana Research | Year: 2012

This paper presents a study of the Middle and Upper Jurassic Ostracods from Western Kachchh, India. The first part discusses the biochronological importance of the Ostracod assemblages, while the second part reports the paleobiogeographical results.Benthic foraminiferal biozones are used to calibrate the biostratigraphical distribution of ostracod species and genera from sections in the Aalenian-Tithonian interval located in Western Kachchh (or Kutch) (Mundham Anticline, Jumara Dome, Jhurio Dome and Habo Dome) and on Pachchham Island (Khavda Nala), Gujarat, India. A total of 71 species are listed, including 32 previously published species and 38 species in open nomenclature, belonging to 23 genera. The ostracod assemblages indicate that faunal communication was first established during the Bathonian and Callovian (Middle Jurassic) and continued until the early Cretaceous. These faunal exchanges occurred between Laurasia (USA, Europe, Russia and Siberia) and the Indo-East African Province, extending along the Western Tethyan carbonate shelves (bordering West and East Gondwana) through to the Pacific Ocean margin of West Gondwana. © 2012 International Association for Gondwana Research. Source


Neto J.V.D.Q.,Petrobras | Sames B.,University of Vienna | Colin J.-P.,Impasse des Biroulayres | Colin J.-P.,University of Lisbon
Journal of Paleontology | Year: 2014

The non-marine Lower Cretaceous ostracod genus Kegelina new genus (Cypridoidea, Cyprideidae) is known from South America (Bahia state, eastern Brazil), West Africa (Gabon and 'Congo'), and North America (Montana, Idaho and Wyoming, U.S.A.). It comprises five species: Kegelina anomala (Peck, 1941) new combination, Kegelina armata (Krömmelbein, 1962) new combination, Kegelina bisculpturata (Wicher, 1959) new combination, Kegelina depressa (Moura, 1972) new combination, and Kegelina kegeli (Wicher, 1959) new combination, all of which having formerly been described as representatives of Cypridea Bosquet, 1852. The closer relationships of Kegelina new genus among the Cyprideidae Martin, 1940 are discussed. Other potential species of Kegelina n. gen. are presumed to occur in northeastern China and Europe but remain to be examined. Copyright © 2014, The Paleontological Society. Source


Seko M.,Slovak Academy of Sciences | Pipik R.,Slovak Academy of Sciences | Colin J.-P.,University of Lisbon | Tarighati M.,Impasse des Biroulayres | And 2 more authors.
Rivista Italiana di Paleontologia e Stratigrafia | Year: 2015

Twelve species attributed to the genus Heliocythere have been recorded from the epineritic/neritic and circalittoral/epi- bathyal deposits of Cenozoic subtropical seas. The oldest species is from the Lower Oligocene deposits of the northwest Indian Ocean. The youngest species are confirmed from the Late Miocene (Messi- nian) of the Mediterranean area and one stratigraphically uncertain record from the Early Pliocene of Vejer de la Frontera (southern Spain). Heliocythere profited of a marine connection between the Mediterranean and the Paratethys through the Slovenian corridor during the latest Burdigalian (Karpatian) and settled in Central Europe and Balkan Peninsula marine biotopes, but a paleogeographic and paleoecologic change during the late Serravallian caused an extinction of Paratethyan Heliocythere. In Late Miocene times, Heliocythere spread through the entire Mediterranean area and extended its biogeo- graphic range to the eastern Atlantic Ocean. This was a period of maximum species diversity of Heliocythere. No Heliocythere species has been described from present-day marine ostracod associations and we suppose that this fully marine genus is extinct. Due to the loss of the type material and the necessary correction of genus attribution, we designate herewith a neotype for the early Badenian (early Langhian) Cythere moravica Prochazka, 1893 from the Carpathian Foredeep, referred to in this work as Heliocythere moravica (Prochazka, 1893). We discuss its paleoecology and position within the genus Heliocythere. Source

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