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1.
A traditional, widely cited hypothesis for over a century posits the origin of the crinoids from blastozoans. The blastozoan hypothesis is contradicted by the discovery of a new crinoid order, the Protocrinoida. Protocrinoids exhibit many traits that are consistent with a basal crinoid phylogenetic position, but inconsistent with a blastozoan ancestry. Protocrinoids are among the oldest crinoids and are therefore stratigraphically correctly placed. The blastozoan hypothesis in contrast, relies on putative homologies between blastozoans and crinoids taken from taxonomically and stratigraphically disparate representatives of both groups; these disparities indicate homoplasy rather than propinquity of descent. Data supporting these ideas are reviewed here. These findings reinforce insightful observations made by Georges Ubaghs decades ago with less data. 相似文献
2.
Apterodon intermedius, sp. nov., a new European Creodont Mammal from MP22 of Espenhain (Germany) 总被引:1,自引:0,他引:1
A mandible fragment of a medium-sized creodont mammal representing a new species of Apterodon, A. intermedius has been discovered in a open cast mine near Leipzig (Germany), dated Late Ruppelian (MP22). For the first time an Apterodon species is well dated in Europe. The dental wear of molars is investigated under SEM. It looks like those described extant carnivores known as preferential flesh eaters. The new specimen together other mammal species questions possible migration ways from Africa to Europe, between the upper Eocene and lower Oligocene. 相似文献
3.
Two new and the only known extinct seahorse species Hippocampus sarmaticus and Hippocampus slovenicus are described from the Middle Miocene beds (Lower Sarmatian) in Slovenia, representing the oldest known fossil record of seahorses. Hippocampus sarmaticus was most similar to the extant seahorse species Hippocampus trimaculatus, while H. slovenicus can be most easily compared to the extant pygmy seahorses H. bargibanti, H. denise, and H. colemani. These Sarmatian seahorses lived among seagrasses and macroalgae in the temperate shallow costal waters of the western part of the Central Paratethys Sea. 相似文献
4.
Sanitheres are enigmatic small suoids with bunoselenodont cheek teeth and a tendency for complication of the premolars by polycuspy and polycristy. Until a few years ago virtually nothing was known about their anterior dentition, but recent discoveries in Greece, Kenya and Namibia have thrown light on their incisor and canine morphology, and reveals among other things that the canines are highly sexually dimorphic, and the dm/1 is replaced by a p/1. Material from Kipsaraman, Kenya, collected between 1997 and 2003, consists of parts of mandibles and many isolated teeth, including elements of the deciduous dentition, a significant proportion of which are unworn. These new finds confirm the aberrant nature of the sanithere dentition within a suoid framework, and support their classification as a family separate from Suidae and Palaeochoeridae (= Old World Tayassuidae).
Résumé
Les sanithères sont de petits Suoïdes aux dents jugales bunosélénodontes avec des prémolaires qui présentent une tendance à la multiplication des cuspides et des crêtes (“polycuspidie” et la “polycristie”). Jusqu’à récemment, on ne connaissait rien sur la morphologie de leur dentition antérieure, mais des découvertes récentes réalisées en Grèce, au Kenya et en Namibie, lèvent le voile sur la morphologie de leurs incisives et de leur canine. Ainsi, il apparaît que les canines sont très dimorphes et que la dm/1 inférieure est remplacée par une p/1. Le matériel de Kipsaraman au Kenya, récolté entre 1997 et 2003, consiste en des fragments de mandibules et de nombreuses dents isolées, dont des dents déciduales, qui pour la plus grande part ne sont pas usées. Ces nouveaux fossiles confirment la nature aberrante de la dentition des sanithères au sein des Suoidea, et supporte leur classification dans une famille distincte des Suidae, et des Palaeochoeridae (= Tayassuidae de l’Ancien Monde). 相似文献5.
Farida Mahammed milie Lng Leïla Mami Larbi Mekahli Miloud Benhamou Boumedine Bouterfa Ali Kacemi Sid-Ali Chrief Hayate Chaouati Philippe Taquet 《Comptes Rendus Palevol》2005,4(8):432
Continental strata of Early and Middle Jurassic age are seldom-exposed, and little is known of the history of sauropod dinosaurs prior to the neosauropod radiation of the end of the Middle Jurassic. Here, we report, in the Middle Jurassic of the Occidental Saharan Atlas (Algerian High Atlas), the discovery of a skeleton, including cranial material, of a new cetiosaurid sauropod. Chebsaurus algeriensis n. g., n. sp. represents the most complete Algerian sauropod available to date, only few remains were found before. To cite this article: F. Mahammed et al., C. R. Palevol 4 (2005). 相似文献
6.
Eduardo Llins Agrasar 《Annales de Paléontologie》2004,90(4):209-222
Study of undescribed material from Dor-El-Talha (Libya, Upper Eocene) reveals the existence of at least three different crocodilian taxa at this locality: a gavialid, a tomistomine and a mesosuchian represented by just one amphicoelous vertebra. Most of this material is fragmentary and it includes mainly fragments of snouts and lower jaws. The crocodilian fauna from this locality shows similarities with that from the contemporaneous El Fayum locality (Egypt).
Résumé
L’étude du matériel inédit provenant de Dor-El-Talha (Libye, Éocène supérieur) indique l’existence d’au moins trois taxons différents de crocodiliens : un gavialidé, un tomistomine et un mésosuchien représenté par une seule vertèbre amphicoele. La plupart de ces matériaux est fragmentaire et elle comprend principalement des fragments de museaux et mandibules. La faune crocodilienne de ce gisement montre des ressemblances avec celle provenant du gisement contemporain du Fayum (Egypte). 相似文献7.
Fernando Emilio Novas Federico Lisandro Agnolín Carlos Agustín Scanferla 《Comptes Rendus Palevol》2010,9(8):499-503
A new enantiornithine bird, Intiornis inexpectatus gen. et sp. nov, is described here. It is based on a partial hind limb found in beds of the Upper Cretaceous Las Curtiembres Formation (Campanian), North-West Argentina. The new taxon is referred to the family Avisauridae on the basis of its cranially convex third metatarsal. Several features suggest close relationships between Intiornis and the avisaurid Soroavisaurus, from the Lecho Formation (Maastrichtian; North-West Argentina). Intiornis was the size of a sparrow, thus representing the smallest Enantiornithes known from South America. The new species shows adaptations for a perching mode of life. Moreover, the hypothesis suggesting that the flying pterosaur reptiles decrease in taxonomic diversity due to competitive interaction with birds is discussed. The new species shows adaptations for a perching mode of life. Moreover, the hypothesis suggesting that the flying pterosaur reptiles decrease in taxonomic diversity due to competitive interaction with birds is discussed. 相似文献
8.
The presence of a large hyaenoid (Hiperhyaena sic leakeyi) from the Late Miocene (Vallesian equivalent) deposits at Nakali, Kenya, was first recorded in 1974, but the fossil on which the announcement was based was not described or figured, nor was a type specimen or type species nominated. The generic and specific names are thus nomina nuda. Howell and Petter (1985) described Hyperhyaena leakeyi, and credited the generic and specific names alternatively to Aguirre and Leakey (1974) and Aguirre and Crusafont in 1974 (the latter paper was never published). Howell and Petter are in fact the authors of both the generic and the specific names. Later in the same paper, Howell and Petter (1985) rejected the name Hyperhyaena and classified the species leakeyi in Allohyaena (Dinocrocuta). The purpose of this paper is to provide more information about the fossil and to discuss its relationships to other percrocutids. It is concluded that it belongs to the genus Percrocuta Kretzoi, 1938, being morphologically similar to the type species Percrocuta carnifex (Pilgrim, 1913) from the Siwaliks of Pakistan. 相似文献
9.
New anthracotheriid remains, discovered by the H-GSP in well-dated localities from the Potwar plateau in the North of Pakistan, between 10.4 and 8.6 Ma, are described and attributed to Merycopotamus medioximus nov. sp. This new species displays an intermediate morphology between the older M. pusillus and the more recent M. dissimilis. These results permit to emend the Merycopotamus diagnosis. To cite this article: F. Lihoreau et al., C. R. Palevol 3 (2004).
Résumé
Une nouvelle espèce d'Anthracotheriidae, Merycopotamus medioximus nov. sp. du Miocène récent du plateau du Potwar, Pakistan. Des restes d'Anthracotheriidae, découverts par le H-GSP dans des localités bien datées du plateau du Potwar, au Nord du Pakistan, entre 10,4 et 8,6 Ma, sont décrits et attribués à Merycopotamus medioximus nov. sp. Cette nouvelle espèce possède une morphologie intermédiaire entre M. pusillus, espèce plus ancienne, et M. dissimilis, plus récente. Ces résultats permettent en outre d'émender la diagnose du genre Merycopotamus. Pour citer cet article : F. Lihoreau et al., C. R. Palevol 3 (2004). 相似文献10.
A new baurusuchid, Wargosuchus australis gen. et sp. nov., coming from the Bajo de La Carpa Formation, Neuquén Province (Argentina), is described. This new taxon is based on a fragment of snout and a portion of the cranial roof. Wargosuchus differs from other crocodyliforms by possessing a deep median groove on the frontals, a contact between nasals and frontals extremely reduced, a large depression for the olfactory bulbs, three large foramina surrounding the large, smooth perinarial depression, and a hypertrophied, conical last premaxillary tooth followed by a large paracanine fossa. The finding of Wargosuchus in Patagonia (Argentina), a taxon with a strong resemblance to Brazilian baurusuchids, reinforces the hypothesis of a similar biota between both regions by the Late Cretaceous. Wargosuchus and Cynodontosuchus represent the only Argentinian mesoeucrocodylians to be included within Baurusuchidae. This finding extends the number of crocodyliforms from the Bajo de la Carpa Formation, which, in turn, corresponds to the most taxonomically diverse one in Argentina. 相似文献
11.
Jean Gaudant Nikos Tsaparas Assimina Antonarakou Hara Drinia Michael D. Dermitzakis 《Comptes Rendus Palevol》2005,4(8):687-695
Although the occurrence of fossil fishes is known since more than one century in the Neogene of Gavdos Island (Greece), its composition remained hitherto unknown. The present study demonstrates that, in the Tortonian of Gavdos, the most abundant species is Bregmaceros albyi (Sauvage), which constitutes two thirds of the collected material. This fish fauna is indicative of an environment of moderate depth, probably corresponding to the external edge of the neritic zone, or possibly to the upper part of the continental slope. To cite this article: J. Gaudant et al., C. R. Palevol 4 (2005). 相似文献
12.
The discovery of a propotamochoerine suid with unique features of the dentition and skull led to the naming of Molarochoerus yuanmouensis Liu & Pan [6]. Further study of the material reveals that this species was better adapted than Sus scrofa for the ‘rooting’ behaviour and that its dentition has morphological features indicating that it was eating hard food items. The posterior premolars are completely molarised, hence the generic name, the first time that any suid has been shown to possess almost perfectly molariform P4/s and p/4s. In lateral view the curvature of the occlusal surface of the upper cheek teeth is convex ventrally, the opposite of the usual situation in suids. The origins of the rostral musculature are exceptionally well developed, and the nasal bones are much more robust than is usually the case in Suinae, indicating powerful musculature and fortified osseous structures presumably for ‘rooting’ in hard ground or for extended periods of time. The masseteric musculature appears to have been more massive than it is in Sus, Microstonyx and Propotamochoerus. To cite this article: M. Pickford et al., C. R. Palevol 3 (2004).
Résumé
Systématique et morphologie fonctionnelle de Molarochoerus yuanmouensis (Suidae, Mammalia) du Miocène supérieur de Yunnan, Chine. La découverte d”un Suidae Propotamochoerini présentant des caractères dentaires et crâniens uniques a conduit à la création de Molarochoerus yuanmouensis Liu & Pan [6]. Une étude du matériel montre que cette espèce était bien mieux adaptée au fouissage que Sus scrofa. Par ailleurs, les caractères morphologiques de sa dentition indiquent qu'il se nourrissait d'aliments coriaces. Les prémolaires postérieures sont complètement molarisées, d'où le nom générique, et c'est la première fois qu'un Suidae présente des P4 supérieures et inférieures presque parfaitement molariformes. En vue latérale, la courbure de la surface occlusale des dents jugales supérieures est convexe ventralement, différant ainsi de la morphologie classique des Suidae. La musculature rostrale est exceptionnellement bien développée et les os nasaux sont beaucoup plus robustes que chez les autres Suinae, suggérant des structures musculaires et osseuses puissantes, probablement liées au fouissage, soit dans des sols, soit sur une longue durée. Les muscles massétériens sont plus puissants que dans les genres Sus, Microstonyx et Propotamochoerus. Pour citer cet article : M. Pickford et al., C. R. Palevol 3 (2004). 相似文献13.
A finely preserved skull with mandible and teeth associated, from the Latest Miocene beds (ca. 6 Ma) of the Pisco Formation, Sud-Sacaco, Peru, represents a new physeteroid genus and species, Acrophyseter deinodon. This moderate size sperm whale is characterized, among others, by: the short rostrum, the mandible distinctly curved upwards, large teeth very close together (12 on each upper tooth row and 13 on each lower tooth row), the lateral margin of the maxilla along the rostrum base much lower than the orbit roof, a wide supracranial basin dorsally overhanging the right orbit and limited to the cranium and a large temporal fossa dorsomedially elevated. A preliminary cladistic analysis provides a phylogenetic position of Acrophyseter nested within the stem-Physeteroidea, more basal than the clade Kogiidae + Physeteridae. The morphology of the oral apparatus and of the temporal fossa suggests that Acrophyseter was able to feed on large preys. 相似文献
14.
Sebastin Apesteguía 《Comptes Rendus Palevol》2005,4(8):503
The fossil record of sphenodontids in the Southern Hemisphere is much longer than in Laurasia, where they became extinct after Early Cretaceous times. Recent works demonstrated the persistence of at least eilenodontine sphenodontids until the ‘mid’-Cretaceous of Patagonia. Focused examination of the Los Alamitos Formation collections provided remains of Late Campanian sphenodontids. Although the phylogenetic position of these remains is still uncertain, they belong to a new, unrecorded species of sphenodontid perhaps related to opisthodontians or primitive, toothed sapheosaurs. To cite this article: S. Apesteguía, C. R. Palevol 4 (2005). 相似文献
15.
The site of Mansourah (Constantine, Algeria) had yielded to the early authors, and more recently to the late G. Laplace, a lithic industry associated with a fauna of large Mammals, which looks contemporaneous with that of Aïn Hanech, although it is well-distinct ecologically, and might even be slightly older. The lithic assemblage is completely devoid of any bifacial artefact or cleaver and can only be referred to the Oldowan. Thus, the Mansourah site documents a very early human occupation of North Africa, and perhaps one of the earliest. To cite this article: Y. Chaid-Saoudi et al., C. R. Palevol 5 (2006). 相似文献
16.
F. Kallel F. Hamza S. Charfeddine W. Amouri K. Chtourou F. Guermazi 《Médecine Nucléaire》2011,35(10):507-516
The aim of our study was to assess the contribution of image fusion of SPECT combined with computed tomography (SPECT-CT) or magnetic resonance imaging (SPECT-MRI) in our daily practice of bone scintigraphy. Seventeen patients underwent a SPECT image fusion, SPECT-CT or MRI in addition to conventional bone scintigraphy. These acquisitions are made separately with images stored in DICOM format. The fusion was operated after a manual coregistration of the images. Results show that in 35.29% of cases, the image fusion allowed to pinpoint the exact location of increased uptake seen on the whole body scan and/or on static images. In 35.29% of cases, the fusion has confirmed a diagnosis doubtful in planar imaging. In five patients, representing 29.41% of cases, the fusion has corrected a diagnosis. In one patient (5.88% of cases), the fusion has eliminated a false positive related to increased uptake visualized on the whole body scan. In two patients (11.11% of cases), the fusion has eliminated false negative of bone scan in one case and of MRI in the other case. Finally, in nine patients (50% of cases), the fusion has influenced the therapeutic management. 相似文献
17.
Remains of a large-bodied species of endemic nesomyid rodent, Macrotarsomys petteri Goodman and Soarimalala, 2005, were identified from subfossil deposits recovered from Andrahomana Cave in extreme southeastern Madagascar. This recently described extant species was previously only known from a single specimen collected at a site about 450 km northwest of Andrahomana and with distinctly different forest habitat than currently found in the vicinity of the cave. Radiocarbon dating of remains of M. petteri from the cave site indicates that it persisted in the region subsequent to human settlement. Previous reports of a large member of Macrotarsomys from other Quaternary sites in southern Madagascar are almost certainly of M. petteri. It is proposed that this species once had a broad distribution across the southern portion of the island during a more mesic period and subsequent aridification of the region has led to its local extirpation across most of its former range. To cite this article: S.M. Goodman et al., C. R. Palevol 5 (2006). 相似文献
18.
An overview of the palaeoneuroanatomy (brain and spinal cord) of the sauropod dinosaur Brachiosaurus is given. Although having a flexed brain configuration, Brachiosaurus presents on the whole a rather moderately derived neuroanatomical pattern. As other sauropods, Brachiosaurus shows an enlargement of the spinal cord in the sacral area. New Encephalization Quotients are calculated and found to be about 0.62 or 0.79 (depending on the body volume taken into consideration) when Hurlburt's formula is used. This suggests that Brachiosaurus, although it may not have been as a low encephalized taxon (by reptilian standards) as previously believed, did have an undersized relative brain volume. 相似文献
19.
Manuel Boizumault Mohssine El Graoui Susan Searight-Martinet Claude Ney Max Schvoerer 《Comptes Rendus Palevol》2010,9(8):505-511
Within the framework of the European Commission's program “Patine du Desert” (DG Research; INCO-CT-FP6-2004-509100), partially concerning the preservation of Saharan engraved rock art, the approach led to the study of the sandstone patina from the rock art site of Oum La Leg (Anti-Atlas, Morocco). The rock and its Tazina school engravings are sometimes covered with a thin brown-ochre coating which only shows a dark patina, the desert patina. This film corresponds to a weathering cortex whose formation is contemporary with wet events from the Holocene period. On the surface, the patinas’ diversity is linked to the heterogeneous distribution of manganese oxides (birnessite and todorokite) due to a reorganisation which led to the incorporation of aeolian silts. Some dating suggestions are made to establish an ante quem age for the engraved lines. 相似文献
20.
Hugues-Alexandre Blain Luis Gibert Carles Ferrndez-Caadell 《Comptes Rendus Palevol》2010,9(8):487-497
For the first time unequivocal fossil remains of a green toad (Bufo viridis s.l.) are described in the Iberian Peninsula. The fossils come from the Cueva Victoria site, a late Early Pleistocene (ca. 1.1–1.2 Ma) karstic filling in semi-arid southeastern Spain (Murcia region). By extension, other remains from two other Early Pleistocene Spanish localities, Barranco León D (ca. 1.3 Ma) and Almenara-Casablanca 3 (ca. 1.1 Ma), are cautiously attributed to the group B. viridis. The B. viridis group was previously reported with some uncertainty to the west of its current distribution area in Western Europe (Spain and France) in the Pliocene (Bufo cf. viridis) and less probably in the Early Miocene (Bufo aff. viridis). Since no osteological differences have been established between the recently described extant species of B. viridis s.l. (e.g. Bufo balearicus, Bufo siculus, Bufo boulengeri, B. viridis sensu stricto and Bufo variabilis) no precise palaeobiogeographical relationships can be drawn for the Spanish fossils. However, the occurrence of a third species of bufonid toad during the Pleistocene in the South of the Iberian Peninsula raises some interesting ecological questions in relation to the local disappearance of the green toad, which can be hypothetically linked to the intensification of the Pleistocene glacial/interglacial climate dynamic or to probable competition with another toad, Bufo calamita. 相似文献