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1.
The recent discoveries of remarkably preserved specimens of Imerites dichotomum (Ammonoidea, Ancyloceratina) bring new palaeontological precisions on this genus. The study of the ontogenic development demonstrates that Imerites directly derives from genus Pseudoshasticrioceras. So, their origin is within the Gassendiceratinae and not in the Heteroceratidae like it was usually admitted. On the other hand, the coexistence of macroconch and microconch specimens in the species of the genus Imerites confirms the hypothesis of a dimorphism. The new palaeontological data prove that “Crioceras” cristatus is a nomen dubium and must be abandoned.  相似文献   

2.
The discovery in the uppermost Jurassic of Lebanon of a species of the ostracod genus Microceratina Swanson, 1980 (Eucytherurinae), of which the oldest known species was until now of Maastrichtian age, confirms the Tethyan origin of this genus. Two new species are created: Microceratina bhannesensis nov. sp. from the Upper Jurassic (Kimmeridgian) of Lebanon, and Microceratina azazoulensis nov. sp. from the Cenomanian of Morocco. The genera Chapmanicytherura Weaver, 1982 and Erratacytheridea Herrig et al., 1997, are considered as probable junior synonyms of Microceratina. An exhaustive bibliographical analysis allowed to identifying several other Cretaceous species susceptible to be assigned to the genus Microceratina.  相似文献   

3.
A microfauna composed of 11 species of ostracodes belonging to 11 genera have been recovered from the Bhanness Formation of Kimmeridgian age, in Central Lebanon. Four species are new and are described herein: Ektyphocythere dahressawanensis nov. sp., Dicrorygma (Orthorygma) libanensis nov. sp., Citrella? elongata nov. sp. and Procytherura inflata nov. sp. From a palaeobiogeographical standpoint, this fauna characterizes the North Gondwana province which differs from the South Gondwana province, particularly by the presence of the genus Schuleridea and the absence of the genus Majungaella.  相似文献   

4.
This work is mainly an answer to the work of Bert, Delanoy and Canut, on the genus Imerites Rouchadzé, and we add also some points to the knowledge of this genus. An answer is given for the implication of one of the authors (J.V.) of this present work, about the origin of the genus Imerites Rouchadzé, and some significant bibliographic references, not named in the 2009 work, are specified and placed in their context. The characteristics of the ornamental stage “Pseudoshasticrioceras” mainly defined by an oval and compressed section of the whorls and by regular ventrolateral clavi, well marked, which frame the venter in a typical way (Bert et al., p. 181), don’t allow to affirm the presence of this stage during the ontogeny of all species of the genus Imerites Rouchadzé, contrary to what Bert, Delanoy and Canut (p. 30, 31) wrote. The type-species of the genus Imerites Rouchadzé is made clear by the application of the rules of the I.C.Z.N. code. The article 23, with the paragraph 23.1 of the I.C.Z.N. code, imply the senior synonymy of Imerites cristatus (Orbigny) on Imerites giraudi (Kilian), even if the Kilian's species is still the type species of the genus Imerites Rouchadzé. The taxinomical validity of the species Imerites cristatus (Orbigny) is confirmed. Its morphological variability is clarified by the distinction of four referential morphotypes, Cristatus, Giraudi, Favrei and Raricostatum. Consequently, the assumption of a shape-dimensional dimorphism into the populations of the genus Imerites Rouchadzé is rejected, awaiting irrefutable proof. A new species, Imerites stephaniae sp. nov., is described. It was collected in the Gerhardtia sartousiana Zone, in the uppermost part of the Gerhardtia provincialis Subzone, and it is a probable ancestor of the cogeneric species of the Imerites giraudi Zone.  相似文献   

5.
The impact of sedimentary conditions on the settlement, growth, and morphology of primitive spatangoid sea urchins of the genus Toxaster from the Lower Cretaceous (Valanginian and Hauterivian of the Provencal platform) is analyzed. The analyses concern spatial and temporal patterns of variation. The spatial approach is based on six isochronous populations of Toxaster granosus kiliani (424 specimens in total) dated from the Verrucosum biozone, and distributed along a proximo-distal gradient. The temporal approach concerns a reference section (Carajuan) ranging from the Lower Valanginian to the Upper Hauterivian, and involving the species T. granosus kiliani and T. gibbus. Sedimentary environments have been characterized by a factorial analysis of five characteristics of facies. Sea urchin morphology has been described with seven measures allowing the computation of two angles (α and β), and of six shape indices analyzed through a principal components analyses. The spatial approach shows that the adult mean size (> 20 mm) increases distally, and that morphology changes significantly across localities. However, only variations in α and β are sequentially organized along the proximo-distal gradient (they correspond to a forward migration of the peristome and to an expansion of the plastronal area). The stratigraphic survey of facies variation along the 369 beds analyzed in Carajuan shows a clear change in sedimentary conditions: from unstable with bioclastic events (Valanginian), to homogeneous with a low content in bioclasts (Hauterivian). Most Toxaster specimens are concentrated in three stratigraphic units (Campylotoxus and Verrucosum biozones for T. granosus kiliani; Sayni biozone for T. gibbus), their abundance being related to the macrofaunal presence and diversity and to burrowing activity. The adult mean size is only significantly related to facies variation, for the T. granosus kiliani from the Verrucosum biozone, increasing with textural gradient and bioclastic content. Shape - facies relationships have been identified for T. granosus kiliani in both Campylotoxus and Verrucosum intervals. However, the morphological variables and facies characteristics involved differ between the two biozones. The synthesis of all significant relationships between size or shape and facies characteristics demonstrates that the response of Toxaster to environmental changes was limited, and varied in space as well as for the different periods of time considered. The only recurring impact of sedimentary changes involved sea urchin abundance, that is, their ability to settle. The low adaptive potential of Toxaster is discussed in the context of the early radiation of the Spatangoida.  相似文献   

6.
The revision of the Crioceras puzosianum d’Orbigny, 1842 made during the revision of the Paléontologie Française of d’Orbigny, shows that this taxon belongs to a new genus: Anglesites gen. nov. This new genus, from upper Barremian age, is monospecific for the moment and is homeomorphic to the Leptoceratoides from the Lower Barremian. It is temporarily included in the subfamily of the Leptoceratoidinae. A neotype for the “Crioceraspuzosianum d’Orbigny, 1842 is herein designated.  相似文献   

7.
During the study of the Quaternary Maghrebian bovines in 1985, the review of the Bovini (aurochs and buffalos) found in Upper Pleistocene sites of Algeria showed that in comparison with most of the African bovine assemblage the attribution of genus Pelorovis to the species antiquus was inappropriate. The biometric and cladistic data revealed a close kinship with genus Syncerus. Later, other authors’conclusions confirmed its relevance. The antique buffalo of the Aterian site of the Phacochoeri has all the characteristics of genus Syncerus, but is different in that it shows a certain number of specific characteristics described in this article.  相似文献   

8.
The Terre noires are monotonous sedimentary deposits comprising thick, dark marls and thin carbonaceous layers. They constitute a lithostratigraphical group known in the major part of the SE French Basin. In the East of this basin this group, dated from late Bajocian to mid Oxfordian, is well developed; on the other hand on the West, it is reduced until it disappears locally on the border of the Massif Central. In the East, the succession is precisely dated by ammonites, whereas in the west, ammonites are not consistently present, and do not permit the same precision. Analysis of dinoflagellate cyst assemblages, at the Callovian-Oxfordian boundary, show that it is possible to correlate the eastern to the western succession. Two marker species allow the correlation of four outcrop sections. The first index, Wanaea fimbriata, is well known; its first appearance datum is exactly at the Callovian-Oxfordian limit in the Boreal and Mediterranean realms. It is the index taxon of the palynological parazone Wfi. The second index, Stephanelytron ceto, an endemic taxon in the SE French, has its last appearance datum within the Scarburghense horizon, the second subzone of the oldest zone of the Oxfordian (Mariae zone). The first section studied was sampled in the east part of the basin (Hautes Alpes department). It corresponds to the maxima of marine deposits and is used as the palynostratigraphical reference. The three other sections analyzed, sampled in the west part of the basin (Ardèche department) where marine deposits are more condensed, are correlated and dated due to dinoflagellate cyst markers observed in the reference section. These results indicate that dinoflagellate cysts are a reliable correlation tool. Batiacasphaera rugosa (Courtinat, 1980) nov. comb is proposed.  相似文献   

9.
Since the middle of 1970s, one rock-shelter, six caves and one open archaeological site have yielded several hominid fossils. Among them, fossils from Yonggok, Mandal, Sangsi and Hungsu cave sites are useful to reconstruct the general shape of the Upper Pleistocene Hominids in Korea. The main study of this paper is to focus on the reconstruction of the general shape of the upper Pleistocene hominids, and to examine the cause of cranial changes from the late upper Paleolithic to Mesolithic period in Korea. Biomechanical principles are also applied to reconstruct the social activity of the upper Paleolithic man in Korea. In addition, it is assumed that main proponent of Paleolithic cultures in Korea might be Homo sapiens rather than any other species. Based on the anatomical characteristics of skull, the axillary border of the scapular and the midshaft of the femur, general appearance of Homo sapiens during the Pleistocene in Korea could be reconstructed.  相似文献   

10.
After the discovery of the controversial hominids and artefacts at the Longgupo site, three Early Pleistocene sites in the southern valleys of the Changjiang (Yangtze) were excavated from 1998 to 2000 in order to test the hypothesis that the hominids exist in China before 2 Ma. Three cheek teeth of Meganthropus palaeojavanicus, more than six hundreds pieces of artefacts of Mode 1 technology and thousands pieces of mammal fossils of Villafranchian age were unearthed in situ at the Longgudong Site in Hubei Province. More than 120 pieces of artefacts of Mode 1 technology and seven thousands pieces of mammal fossils of Villafranchian age were unearthed in situ at the Renzidong Site in Anhui Province. Although no new materials of hominids and artefacts were unearthed at the Yuanmou Man Site at Danawu in Yunnan Province, new materials of mammalian fauna confirm the horizon yielding the Yuanmou Man fossils is of the Early Pleistocene. These new discoveries imply that the appearance of hominids in China is very likely before 2 Ma. If the new report of 3 Ma artefact from Yuxian of the Nihewan Basin in northern China can be confirmed, it will be a strong support for the Continuity Theory.  相似文献   

11.
12.
The Permian section outcropping at Guardia Pisano (Sulcis area, SW Sardinia), comprises two successions, separated by an unconformity. The lower succession is composed of grey-black sandy shales, rich in plant remains and in sporomorphs, deposited in a fluvial-lacustrine to palustrine environment; followed by layers of rhyolithic lavas and volcanoclastites with silicified plant trunks. Most of the analysed samples yielded a profusion of pollen and spores in a very good state of preservation. Three associations were distinguished. The first one comprises mostly radial and bilateral monosaccate pollen grains and very few spores. This association is characterized by the presence of pollen grains of the genera Crucisaccites, Luberisaccites, Gondwanopollis and Lueckisporites, together with very abundant Potonieisporites and subordinate Florinites. The second association comprises mostly pollen grains of the genus Potonieisporites, represented by many species, together with Limitisporites, Costapollenites, Vittatina and others. Spores mainly represented by azonate trilete and monolete types are more frequent than in the previous association. These first two palynological associations reflect assemblages of meso-xerophilous plants growing in dryer environments, belonging to tropical and subtropical phytogeographic biomas. The third association, mainly composed of Sphenophyte spores, is autochthonous and corresponds to a swampy hygrophilous flora settled after the filling up of the basin. The age inferred by means of sporomorphs is early Asselian which is in good agreement with the mean radiometric age of the volcanic rocks obtained by the ‘SHRIMP’ and the lead-zircon evaporation methods (297 ± 5 Ma). The upper succession, is composed of grey to red sandstones and thin pelites deposited on an alluvial plain under very hot and humid climate; its Permian, post-Asselian age cannot be better constrained because of the scarcity of the fossil content.  相似文献   

13.
This work is mainly an answer to the work of Bert (2009), on families Helicancylidae Hyatt, 1894 and Acrioceratidae Vermeulen, 2009. On the nomenclatural speaking, the non validity of the genus Helicancylus Gabb, 1869 and of the family Helicancylidae Hyatt, 1894 and, consequently, the validity of the family Acrioceratidae Vermeulen, 2004 are established. The second part of this work is devoted to the respect of former work and, contrary to the assertions from Bert (2009), it is shown that the stratigraphical positioning of the Upper Barremian level with small Barremites, realized by Cotillon (1971), is at least as precise as that proposed by Bert. The last part of this work highlights a lack of bibliographical references, fact which had already been highlighted ( Vermeulen and Lepinay, 2010) in a former work of Bert et al. (2009).  相似文献   

14.
This paper provides an overview of current knowledge of Plio Pleistocene Carnivora from Africa and Europe. In Plio Pleistocene times, many genera extend their ranges in Africa and Eurasia but their evolution are quite distinct in the two continents. In Africa, the modern carnivoran guild of sub saharian Africa originated in the early Pleistocene when took place extinction of archaic species. The north African fossil record is far from complete until the middle Pleistocene. In the middle and late Pleistocene, the modern carnivoran guild is associated with other elements: the simian jackal Canis simensis and two species of ursids Ursus arctos and Ursus deningeri which evolved towards Ursus spelaeus. Western European carnivore faunas show due to migration a constant turn-over of the species. Among felids, Panthera schaubi described by Viret (1954) and attributed to the genus Puma by Hemmer et al. (2004), is morphologically close to the snow leopard Panthera (Uncia) uncia. Canis etruscus is the sister group pf the clade including wolf and coyote and Canis arnensis is close to the African jackals. Ursus deningeri appears in the early Pleistocene together with two arctoid forms Ursus rodei and Ursus dolinensis that may be synonymous to Ursus arctos. The genus Hyaena is present in Europe in the middle and late Pleistocene.  相似文献   

15.
Hundreds samples of the charcoals and waterlogged woods excavated from three late Paleolithic sites (Suyanggae, Gunang-gul and Sorori) in the Jungwon Region in Korea were analyzed to reconstruct the vegetation and paleoclimate in the region. Analyzed charcoal samples from the Suyanggae site show that the climate was cold in the lower part and it became more warm and dry in the upper part. From the Gunang-gul site, only Picea spp. was identified, indicating cool climates. From the Sorori site, two species were found; Alnus spp. (95%) and Ulmus spp. (5%). No conifers were discovered. The species composition indicates that the climate condition of central Korean peninsula around 8,800 BP was little cooler and wetter condition.  相似文献   

16.
Three Megacricetodon species are recognized in the Middle Miocene locality of Blanquatère 1 (Languedoc-Roussillon province, France). Two are new, the small-sized M. tautavelensis nov. sp. the medium to large-sized M. aunayi nov. sp., the third one being the already known M. “collongensis-gersii”, a medium-sized species found in other Miocene localities of the area. Size and morphology differentiate these species. Such a high number of contemporaneous species of the genus Megacricetodon is found for the first time in a Miocene locality in the region and indicate that the evolution of this genus in western Europe is likely more complicated. It may testify both of a biogeographical differentiation and of migration events. According to our calibration charts, the deposit is dated ca. 16 Ma ago. The position of Vieux-Collonges (MN 5) and Sansan (MN 6) on the biochronological scale is also discussed, as well as the estimated age of the biozonal boundaries MN 3/MN 4, MN 4/MN 5 and MN 5/MN 6.  相似文献   

17.
The classification of the Paris basin Bajocian-Oxfordian species of the genus Nucleolites is revised. A classic point of view, until now used by authors and mainly based on the general morphology of the test, is first developed. Then, this last is modified with new architectural data, which refer to the extraxial-axial theory concerning the structure of the apical system as well as the presence of supplementary and catenal plates. These architectural data are first used facing the general morphology of the test. Such approach leads to a new point of view for the classification of the species of the genus Nucleolites. The systematics is particularly significantly simplified. The deduced and proposed phylogenetic hypothesis shows that the genus Nucleolites is composed of two parallel lineages as soon as the beginning of the genus in the Bajocian: a group with a so-called “primitive” architecture, and a group with an “advanced” one. On and after the Late Callovian, the species with a primitive organisation give birth to advanced species, which continue in younger time. In this way, the genus Nucleolites may be paraphyletic since the Late Callovian onward.  相似文献   

18.
The Jungwon region is located in the central part of Korea and it is one of crucial regions for understanding of the Korean Paleolithic culture. Many Paleolithic sites have been discovered in this region, from the lower Paleolithic to the upper Paleolithic. It is of interest the remarkable variety of archeological remains such as human bones, stone tools, animal bones and paleoenvironmental artifacts. As a result, it permits us to reconstruct the subsistence of prehistoric men. This region has an important role for Korean prehistoric researches.  相似文献   

19.
Eight new species of the family Cytheridae have been identified in the Upper Miocene deposits of the Turiec Basin (Slovakia), a small isolated intermountain depression. Six species are new - Euxinocythere aphroditae, E. delicata, E. lactea, E. minuscula, E. quadricostata, E. satyrica - and two are kept in open nomenclature. Their attribution to the genus Euxinocythere is based on arrangement of the hinge elements and of anterior marginal zone. This genus is known from brackish ostracod assemblages of the Paratethys and the Eastern Mediterranean while the species from the Turiec Basin are associated to fresh-water assemblages. The Euxinocythere have been found in littoral as well in deep limnic environment.  相似文献   

20.
The lion's share of articles dealing with the thumb anatomy of Plio-Pleistocene hominids has focussed on the capacity to manipulate and manufacture tools, and has largely neglected the locomotor aspects. However, in these hominids, the forelimb was still employed in locomotion. Certain of the anatomical characters classically associated with manipulation and/or fabrication of tools are already present in the Late Miocene species Orrorin tugenensis as shown by the terminal thumb phalanx BAR 1901'01. This specimen reveals crucial information suggesting that thumb morphology is not exclusively related to such tool using and manufacturing activities but reflects in a frequently bipedal creature a deeper adaptation concerning the precision grip essential for climbing and balancing, different from that of apes.  相似文献   

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