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61.
Paleogene sedimentation in the Alpes Maritimes and Alpes de Haute Provence regions is composed of one complete sedimentary sequence. This sequence begins with the continental Formation from Microcodium and continues with the Cerithium layers, the Calcaires Nummulitiques and the Marnes Bleues, which are overlaid by the turbidites of the Grès d’Annot Formation. Sedimentation starts in the Nummulites perforatus zone close to the base of ‘the Truncorotaloides rohri zone (P 14) and ends in the Cassigerinella chipolensis-Pseudohastigerina micra zone (P 18) and the NP21 zone in the upper part of the Grès d’Annot. More biomarkers were used in order to define a more detailed local biozonation (biozones AMP 1 to AMP 7). Four local zones were also defined by the last occurrence of Nummulites millecaput and N. perforatus-N. ptukhiani and then by the first appearance of N. retiatus (AMGF 1-4). The evolution of benthic foraminiferal assemblages shows an increase in bathymetry from the internal platform in the Cerithium layers to the calcareous platform with large foraminifers, then to the external platform and the deep offshore environment of the Marnes Bleues and Grès d’Annot. Low faunal diversity in the Grès d’Annot together with the predominance of agglutinated species indicates a poorly oxygenated, organic rich and turbidite environment. Seven steps (SD 1 to SD 7) in the Eocene marine transgression are shown from East to West by detailed local biozonation and sequence analysis. Grès d’Annot sedimentation is also diachronous, beginning within the Truncorotaloides rohri zone (P 14, AMP 1) in the East and ending within the Pararotalia opima opima zone (P 20, middle Rupelian) in the West (Barrême). Small foraminifer Paleogene fauna from the Alpes Maritimes and Alpes de Haute Provence was studied from 400 samples. It is composed of 378 species. Two new taxa are proposed: Fissurina niceana n. sp. and Globocassidulina alpina n. sp. The species from the Escarène and Gorbio neighborhood described by M. von Hantken (1884) were re-examined.  相似文献   
62.
Dasypsyllus picaflori n. sp. est décrit à partir de puces prélevées dans un nid de Trochilidae, Oreotrochilus leucopleurus Gould 1847, au Chili. C’est la deuxième espèce de Puce signalée chez des Colibris. Taxonomie, répartition, spécificité et écologie des espèces et sous-espèces connues dans le genre Dasypsyllus sont rappelées.  相似文献   
63.
《Comptes Rendus Palevol》2018,17(6):335-345
Along with the early age obtained for the cultural remains attributed to anatomically modern humans from Kaldar Cave, the archaeological assemblages recovered from both Kaldar and Gilvaran Cave located in the Khorramabad Valley (Iran), have yielded charcoal remains that allow the identification of Prunus spp. These remains correspond to the Middle and Upper Palaeolithic, which are the earliest finds attesting to the presence of this taxa in the area. Our anatomical observation of the samples revealed the presence of Prunus spp. (plums) and Prunus cf. amygdalus (cf. almond). This also reflects specific plant communities in the area, characteristic of open forest growing in cool, dry conditions. These results provide new insights into the arboreal cover in this area during an Upper Pleistocene period. Furthermore, anthracological evidence together with other contextual materials provides new clues to assess how Neanderthals and early modern humans adapted to their surrounding landscape, and their relationship with their environment in this region and beyond.  相似文献   
64.
The complete late Campanian–Maastrichtian succession of the South Atlantic reference DSDP Site 525A has been investigated to establish a detailed record of calcareous nannofossil biohorizons. A complete holostratigraphy of the core is presented for this interval and allows for global correlations to other Tethyan and Boreal reference sections for that interval. The new study allows for proposing a new time scale with a tie of Tethyan and Boreal nannofossil zonations. A new subzonation is proposed for the late Campanian UC16 Zone in the Tethyan Realm and the last occurrences of Uniplanarius trifidus and Zeugrhabdotus praesigmoides are demonstrated as markers of the Campanian–Maastrichtian boundary. The difference between cumulative first and last occurrences reflects the turnover dynamics of calcareous nanoplankton in the South Atlantic and highlights 6 major events. Five of them appear well related to major changes in sea-surface temperatures whereas the sixth event is likely the expression of a global decrease in primary productivity in the late Maastrichtian. Surprisingly, the turnover dynamics in calcareous nannoplankton appears completely unrelated to that observed in planktic foraminifera which shows only 4 major events with different timings. The two groups thus seem to have responded either very differently to similar environmental constraints or to different direct environmental constraints in the photic zone, although caused by the same global changes in climate.  相似文献   
65.
Here we present morphometrical evaluation, biogeographical distribution patterns and ecological information for five coccolithophore taxa (Calcidiscus leptoporus, C. leptoporus small, C. quadriperforatus, Umbilicosphaera foliosa and U. sibogae). This information is based on data obtained from surface sediments from the South Atlantic. The three Calcidiscus taxa can easily been distinguished by a combination of size and qualitative characters of their distal shields. Mostly encountered in the temperate to sub-polar regions C. leptoporus is the most abundant taxon and exhibits a negative correlation to temperature and salinity. Both, C. leptoporus small and C. quadriperforatus reach their maximum abundances also at higher latitudes and in the SW-African upwelling area. Their distributions therefore suggest preference for nutrient-enriched waters, which is also indicated by CCA. The two circular Umbilicosphaera species exhibit significant differences in coccolith morphology and show little overlap in size. Highest abundances are encountered in sub-tropical latitudes and are mainly derived from U. sibogae. In contrast, U. foliosa is present in very low abundances. Both species exhibit a preference for warm and oligotrophic conditions. However, U. foliosa increases in relative proportion to U. sibogae at the southernmost locations and in the Benguela upwelling. This could be interpreted as an affinity for slightly cooler and nutrient-enriched environments.  相似文献   
66.
Bernard Walter 《Geobios》1985,18(1):5-45
Study of new and important collections of bryozoa in Neocomian of the French and Swiss Jura improve the knowledge of these Bryozoa, especially the “mesenteripores” (Tubuloporina with bilamellar structure) of which almost all the species types proceed from the Jura. These species are here redefined, for example M. campicheana which was poorly known until now. One new species, Mesonopora uniordinata, is described. To this superior delimitation of species, is added extensed geographical distribution and also more precise stratigraphical position. The fauna of mesenteripores varies according to lithostratigraphy, that is to say, with variations of paleoenvironment. Among these, modification of substratum, sedimentary deposition, depth, are the easiest to envisage.  相似文献   
67.
Black carbonate rocks («ampelitic limestones)exposed in la Meignanne, NW of Angers, Massif Armoricain, as tectonic lenses within a complex tectonic structure of grey Pragian limestones are assigned from Bivalvia and Chitinozoa to the Upper Silurian and Lowermost Devonian. Biostratigraphical and paleoecological analyses show that the Silurian-Devonian boundary in this area is developed in offshore facies and that it may be correlated directly with the international stratotype of the Prague Basin (Barrandian, Bohemia). Paleogeographical communication between the two areas is indicated by 28 species of bivalves in common from two Pridolian assemblages (with Cheiopteria bridgei and with Snoopyia insolita) and one Lochkovian (with Antipleura bohemica). Stratigraphical correlation with the Prague Basin is also based on the chitinozoan zonal index species for the Uppermost Pridolian (Urnochitina urna) and Lowermost Lochkovian (Eisenackitina bohemica). A Lochkovian age is further supported by the discovery of Monograptus uniformis uniformis in the assemblage with Antipleura bohemica. A Ludlovian age is indicated by the occurence of «Hemicadium elevatum and an abundance of the ostracode Entomozoe (Richteria) migrans, which is an index species for the Middle Ludlovian in Bohemia.  相似文献   
68.
Lawrence J. Flynn 《Geobios》1982,15(4):583-588
Based on the biochronology of rhizomyid rodents of Northern Pakistan, fossil horizons in the Siwaliks of Northern India can be correlated to the late Neogene sequence of Pakistan with greater precision than previously possible. The indian Siwaliks do not include records of the most primitive Rhizomyidae, but rhizomyid faunas of India display strong affinity with those of Pakistan in the late Miocene. Pliocene differentiation of rhizomyid faunas in India and Pakistan may reflect ecological partitioning within the Indian subcontinent. Use of the term «Nagri for deposits at Haritalyangar suggests an erroneous equivalence in age to the Nagri stratotype in Pakistan.  相似文献   
69.
Annick Boullier 《Geobios》1981,14(1):29-67
The questions relating to the type-species of genus PostepithyrisMakridin and to its systematic position within Terebratulids are discussed.The French species are described: besides the type-species P. cincta (Cotteau) from Upper Oxfordian, two species from Inferior Kimmeridgian can be included in this genus: P. minor (Douvillé) and P. dubisensis nov. sp.A new subspecies P. cincta mosensis nov., recently discovered in Oxfordian from East of the Paris Basin, can also be assigned to the genus.Postepithyris did not evolve through a single special facies: the species could supported different environmental conditions.  相似文献   
70.
The rich Cenomanian assemblage of tube-dwelling polychaete worms of the families Sabellidae and Serpulidae from Le Mans region (Sarthe) is described in detail for the first time in one place; the systematics and the palaeoecology of the species are discussed. The 19 species described belong to 12 genera: Glomerula Brünnich Nielsen, 1931; Filograna Berkeley, 1835; Protula Risso, 1826; Filogranula Langerhans, 1884; Serpula Linnaeus, 1758; Cementula Brünnich Nielsen, 1931; Neovermilia Day, 1961; Dorsoserpula Parsch, 1956; Mucroserpula Regenhardt, 1961; Placostegus Philippi, 1844; Cycloplacostegus Jäger, 2005; Pyrgopolon de Montfort, 1808. Two new species are described: Serpula? pseudoserpentina sp. nov. and Pyrgopolon (Septenaria) cenomanensis sp. nov.  相似文献   
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