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1.
The postcranial anatomy of the Asian sivaladapid adapiforms is still virtually undocumented, whereas dental remains of these primates have been known for several decades. Little is known about their positional behavior as a result. In this article, we describe a partial left femur of a medium-sized primate preserving its entire proximal portion and a significant length of its shaft. This fossil was recently recovered from the fossiliferous locality of Thamingyauk in the late middle Eocene Pondaung Formation (central Myanmar). This femur is considered to pertain to the same individual as two tarsal elements (fragmentary talus and calcaneus) from the same locality (same location), and attributed to a medium-sized sivaladapid adapiform primate (Kyitchaungia takaii). This new postcranial element provides the first documentation of femoral anatomy among Sivaladapidae from Asia. The mechanical implications deriving from the musculoskeletal interpretation of this bone indicate an animal that probably engaged in a kind of active arboreal quadrupedalism with some degree of proficiency in leaping. Even though many musculoskeletal aspects suggest that branch walking and running were important parts of its locomotor repertoire, in other details it appears that relatively complex movements at the hip joint were actually possible and probably associated with climbing or some hindlimb suspensory activities.  相似文献   

2.
Tapejarids are edentate pterosaurs recovered mainly from Early Cretaceous deposits. They are diagnosed by five synapomorphies, among which only one is postcranial: a broad and well‐developed tubercle at the ventroposterior margin of the coracoid. Regarding the clade Thalassodrominae, most phylogenetic studies are based on cranial elements, as postcranial skeletons of these pterosaurs are rare. Here, new postcranial material from the Romualdo Formation (Aptian–Albian) from the Araripe Basin is described. The material comprises the three posteriormost cervical vertebrae, the first seven dorsal vertebrae (fused into a notarium), both scapulocoracoids, a fragment of a sternum, a partial right humerus, a small fragment of a 4th phalanx of the wing finger, a distal extremity of the right femur and the proximal portions of both tibia and fibula. Comparisons with other specimens and morphological features examined in a phylogenetic context, such as the presence of three foramina lateral and dorsal to the neural canal of the cervical vertebrae, the presence of a notarium and a pneumatic foramen on the ventral side of the proximal portion of the humerus, allow the assignment of this specimen as Thalassodrominae indet. Regarding palaeobiogeographical aspects, to date, this clade is exclusively found in the Romualdo Formation. It is the most complete postcranial material assigned to the Thalassodrominae described so far.  相似文献   

3.
A series of fossil cercopithecoids has been recovered from the Dawaitoli Formation, in the Middle Awash study area, Ethiopia. The Dawaitoli Fm. has been dated to approximately 600 Ka. This series includes several partial crania of Theropithecus oswaldi leakeyi as well as other cranial and postcranial fragments. This material is some of the most complete to date and adds considerably to what is known of this widespread and abundant taxon. There are also two isolated papionin molars here allocated to Papio cf. hamadryas based largely on size grounds and similarity to contemporary material from other sites in the Afar Depression. Cercopithecoids are rare in the Dawaitoli Fm., and among them only large papionins are known. This is unique among known Pleistocene sites in the Afar region, but is most similar to the Daka Member of the Bouri Formation. It is quite different from the other known Middle Pleistocene sites in the Afar: Asbole and the geologically younger Andalee where cercopithecoids are abundant and colobines predominate.  相似文献   

4.
The clade Tapejaridae is composed by pterosaurs commonly found in fossiliferous deposits in northeastern Brazil. It is constituted by two less inclusive clades: the smaller-bodied Tapejarinae and the larger Thalassodrominae. Here we describe the specimen MN 6566-V, from the Lower Cretaceous Romualdo Formation of the Araripe Basin, Brazil. The specimen is overall well preserved tridimensionally, and consists of three posterior cervical vertebrae, incomplete right and left scapulocoracoids, and the proximal portion of a right humerus. Comparisons to specimens described in the literature enable its identification as a thalassodromine, whose postcranial material is still poorly known despite the large amount of pterosaurs known from this unit.  相似文献   

5.
Abstract:  A new taxon of theropod dinosaur is described as Condorraptor currumili gen. et sp. nov., from the Middle Jurassic (Callovian) Cañadón Asfalto Formation of Chubut Province, Argentinean Patagonia. The taxon is represented by a single fragmentary postcranial skeleton. Although incompletely known, Condorraptor is the second most complete theropod from the Middle Jurassic of Gondwana. The new taxon is characterized by the absence of a posterior incision between the fibular condyle and the medial side of the proximal articular end of the tibia, the pleurocoels in the anterior cervicals being situated posteroventral to the parapophyses, and the presence of a pronounced 'step' between the distal articular facet and shaft of Mt IV. Pneumatic features of the vertebral column show strong variation between the left and right side. Condorraptor gen. nov. can be referred to the Tetanurae and is a representative of a global radiation of basal tetanurans in the Early to Mid Jurassic.  相似文献   

6.
7.
703 standardized test specimens of dry cortical bone from different shaft regions of human femora were subjected to compression till failure parallel to the long axis of the shaft. The rate of load increase was 50 kg/cm2/sec. The significance of four sources of variation was tested, i.e. cross-sectional area (site), quadrant (position), side of the body, and individual, in three analyses of variance. All main effects and the interactions site x position, site x individual, position x individual, body side x individual are significant. A constant pattern of strength distribution in the proximal three cross-sectional areas is shown: this pattern is changed in the two distal cross-sectional areas, but it is the same on the left and right sides of the body apart from variations by the main effects. The pattern of strength distribution in the two distal cross-sectional areas probably changes with age. The distributions of mean compressive strength of femur shafts from two age groups are presented diagrammatically in Fig. 1, and the respective means are given in Fig. 2.  相似文献   

8.
A postcranial skeleton of a representative of the palaeognathous Lithornithidae (Aves) is described from the Middle Eocene of Messel in Germany. The specimen is slightly smaller than Lithornis plebius from which it, however, differs in limb bone proportions. It constitutes the latest fossil record of the Lithornithidae in Europe, whose only other Middle Eocene record is a fragmentary tibiotarsus from North America.  相似文献   

9.
The findings of the histological study of the human temporomandibular joint confirm that the cranium and the lower jaw are jointed by two temporomandibular articular complexes (one on the left and another on the right side), each made up, in turn, of two joints--a condylomeniscal condyloarthrosis and a reciprocally fitting meniscotemporal joint. Both these joints are surrounded by short capsular bands which stretch from the condyle to the meniscus and from the latter to the temporal bone and form the true joint capsules. Longer bands which extend from the condyle to the temporal bone may be regarded as reinforcements passing over two articulations.  相似文献   

10.
11.
侏罗纪的蛇颈龙类化石主要发现于欧洲 ,在世界的其他地区则比较少见。亚洲的蛇颈龙化石 ,尤其是侏罗纪的属种大多破碎而难以鉴别 (Sato,1 998)。到目前为止 ,Bishanopliosaurusyoungi(Dong,1 980 )和Yuzhoupliosauruschengjiangensis(Zhang,1 985)是亚洲地区最为完整的侏罗纪蛇颈龙类化石 ,并且化石产自对于蛇颈龙而言比较罕见的淡水沉积 ,因此这些材料对于了解该类群的系统发育、历史动物地理和古生态来说非常重要。本文重新详细描述了采自中国重庆自流井组东岳庙段的杨氏璧山上龙2 ) (董枝明 ,1 980 )。愈合情况不好的椎体和椎弓以及耻骨的边缘形态表明 ,杨氏璧山上龙的正型标本是一个幼年个体的头后骨架。我们的研究表明杨氏璧山上龙主要依分叉的荐肋为特征 ,而这一性状在初次发表时作为颈肋特征被描述。璧山上龙的其他特征包括侧扁的神经棘以及狭窄的乌喙骨和肱骨上有一个突。经过重新修理的标本显示 ,坐骨和耻骨相对的面呈沟槽状 ,这一现象表明它们之间的接触关系要较原来描述的情况复杂 ,是一种依靠软骨的连接 ,而非直接接触。本文对杨氏璧山上龙的腰带部分进行了重新复原。O’Keefe (2 0 0 1 )的支序分析支持将Plesiosauria二分为Plesiosauroidea和Pliosauroidea,后者包含两个科 :Pliosauridae和  相似文献   

12.
准噶尔盆地北缘哈拉玛盖组中的Anchitherium   总被引:1,自引:1,他引:0  
发现于新疆准噶尔盆地北缘中新世哈拉玛盖组中的安琪马过去都被归入Anchitheriumaurelianense种。近年来在该地区新发现的Anchitherium的材料表明新疆准噶尔盆地北缘中新世哈拉玛盖组中的安琪马具有Anchitheriumgobiense的特征:上臼齿的原小尖弱但可辨认,次附尖较发育并与后部齿带共同封闭成一三角形窝,前齿带发育但内齿带弱;下颊齿相对较宽,下颊齿齿叶呈V形,外端显得较为尖锐;下臼齿列由前向后明显变窄;距骨较高窄。这些特征均与内蒙古通古尔的AnchitheriumgobienseColbert,1939一致,而与欧洲的A.a.aurelianense、A.a.steinheimense及A.a.hippoides者不同。因此哈拉玛盖组中的安琪马应归属Anchitheriumgobiense。我国湖北房县的安琪马也应是A.gobiense种。A.gobiense的前臼齿列的宽度由后向前,尤其是臼齿列的宽度由前向后减小的程度,大于欧洲的A.aurelianense种,这一特征与下颊齿相对较宽、齿叶外端较尖锐、上颊齿的内齿带弱等特征一起组成了中国Anchitherium支系的特征。中国的三趾马化石层位中的大型安琪马Sinohippuszitteli具有明显不同于欧洲安琪马类的特征:1)齿冠很大,上颊齿外脊的外壁呈宽V形;2)其前臼齿列及臼齿列的宽度分别向前和向后明显变小,特别是下前臼齿列向前变窄的程度远超过安琪马属。因此应保留Sinohippus属,Sinohippuszitteli是亚洲大陆上特有的安琪马支系的晚期代表。  相似文献   

13.
The fragmentary remains of a juvenile rhabdodontid ornithopod from the Coal-bearing Complex of the Gosau Group (Lower Campanian, Grünbach syncline) at Muthmannsdorf near Wiener Neustadt, Lower Austria are revised. The material, probably belonging to a single individual, includes a right dentary (lectotype of Iguanodon suessi Bunzel, 1871, designated herein), teeth, a fragmentary parietal, fragments of scapula, ?radius, femur, tibia, two vertebrae (lost) and a manual ungual.The lectotype dentary does not provide clear autapomorphies or sufficient diagnostic features to determine its position within the Rhabdodontidae at generic level. By this “Iguanodon suessi” Bunzel, 1871 and the genus “Mochlodon” Seeley, 1881, to which it was latter referred as type species, cannot be characterized sufficiently by differential diagnosis and these are best considered nomina dubia. Based upon combined character comparisons (mainly postcranial features) the Muthmannsdorf ornithopod is referred herein to Zalmoxes Weishampel, Jianu, Csiki and Norman, 2003, a genus so far known from the late Maastrichtian of Romania. It probably but not evidently represents a yet unnamed species, most closely related to Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. At the present state of knowledge the Austrian material is not further diagnostic at the species level and kept in open nomenclature as Zalmoxes sp.  相似文献   

14.
《Comptes Rendus Palevol》2013,12(5):279-291
Identification of the individuals represented in a fragmentary fossil assemblage is a key step in paleobiological research, as ensuing organism-level studies, as well as sampling strategies (e.g., DNA, isotopes, dating, etc.), may depend on the reliability of such estimates. In the human fossil record, dental remains represent the most abundant and informative material, allowing individual identification on the basis of a variety of diagnostic criteria. In this paper, we present a procedure for sequential association of the dental remains and the identification of the minimum number of individuals (MNI) represented in the 49,000-year-old Neandertal assemblage from El Sidrón (Asturias, Spain). In order to quantify the possible association errors, the 12 criteria used in this study are organised according to three levels of reliability. Following this procedure, a minimum of 13 individuals (seven adults, three adolescents, two juveniles and one infant) have been identified at El Sidrón, two of them uniquely represented by postcranial elements. A next step in this investigation foresees the development of methods for associating postcranial elements with the dentally-based identified individuals.  相似文献   

15.
Bone involvement of hydatid disease is uncommon but when encountered, it presents few unique pathological features. The pattern of tissue involvement is largely different from that of visceral hydatid cyst. We describe the case of a 47 year-old man from northern India, a case of systemic hydatidosis including the liver and the right lung, presenting with an abscess like lesion in the left gluteal region with pathological fractures of the left femur. Radiographs and CT-scan images showed extensive invasion of the left hemi-pelvis and left proximal femur. Debridement of the honeycombed ilium yielded hydatid fluid, numerous small cysts and necrotic material. Multiple large devitalized and sequestrated bone pieces were recovered from the bone cavity of the affected ilium. A histopathological study of the bone sequestrums revealed the unique pattern of bone invasion by the characteristic laminated multi-layered cyst walls into areas of least resistance. Bone sequestration has not often been described or demonstrated elaborately in published studies of the past. The bone defects formed after debridement of the ilium and proximal femur were filled with bone cement along with augmentation of the femur using intra-medullary nail. The surgical technique adopted in our case although was not expected to be curative owing to the multi-system disease; it did result in significant functional improvement in the patient.  相似文献   

16.
17.
Marzia Breda 《Geobios》2005,38(2):151
Alces alces, Cervalces and Megaloceros giganteus are deer of approximately the same size whose limb bones could be exchanged if fragmentary so morphological features are needed, enabling identification of postcranials remains. In this work the limb bone features described by Pfeiffer (1999a) as distinguishing Cervalces latifrons from M. giganteus are re-analyzed and further developed, considering also the vertebral column, the articular girdles and the carpals and tarsal elements. This analysis is extended to the other Cervalces species (C. gallicus, C. carnutorum and C. scotti) and to the present-day moose Alces alces. It results in a substantial uniformity in the postcranial skeleton of the species of the genus Cervalces, confirming what has already been stated by Sher (1987), that the Alceini, in the Upper Pliocene, constituted an already well-defined morphological type that did not undergo further structural postcranial remodeling.  相似文献   

18.
《Comptes Rendus Palevol》2018,17(8):504-521
The Bajo de la Carpa Formation (Santonian) of the Neuquén basin (southwestern Argentina) has one of the most complete crocodyliform records of South America, together with the Adamantina and Marília formations of Brazil. In this contribution we report two fragmentary individuals from two different localities of the Bajo de la Carpa Formation: a middle-sized individual (MLP 26-IV-30-2), represented by postcranial remains from the Boca del Sapo locality and a large-bodied individual (MACN Pv-RN 1150), consisting only of snout elements from Paso Córdoba locality. Despite the remains of both specimens are fragmentary, they display anatomical characters of a specialized notosuchian carnivore clade: Baurusuchidae. Our phylogenetic analysis recovers these new individuals as non-baurusuchine baurusuchids, although they take multiple phylogenetic positions on the different most parsimonious trees. These new remains highlight the relevance of the Bajo de la Carpa Formation for understanding the rise of notosuchians during the Late Cretaceous.  相似文献   

19.
Visually seriated radiographs of the proximal femur, proximal humerus, clavicle, and calcaneus from 130 individuals from the Hamann-Todd collection were examined as indicators of skeletal age at death. The clavicle demonstrated the most consistent relationship to age in both sexes. The same radiographs were also seriated by size-normalized optical density as a means of establishing relative radiolucency. In this context, visual seriation proved superior. The four sites studied showed strong divergence in response to age. Since each was sampling bone response from the same individual, it is concluded that bone loss is highly site specific. This demonstrates the individual character of specific skeletal sites. Visual inspection of clavicular radiographs, seriated on a populational basis, provides age estimates that are comparable to anatomical age indicators and provides independent estimates of skeletal age when included in the summary age method (1985: Am. J. Phys. Anthropol. 68:1–14).  相似文献   

20.
Canal systems in the temporal bone and their right-left differences   总被引:1,自引:0,他引:1  
J Lang  C Hack 《Acta anatomica》1987,130(4):298-308
The first part of the facial canal is the pars labyrinthica. Its means lateral length is in our material 2.63 mm on the right and 3.03 mm on the left side. The mean width of the pore on the fundus area was 1.3 mm on the right side and 1.07 mm on the left. The geniculate fossa had a mean length of 2.54 mm on the right and of 3.14 mm on the left side. The widths of different areas of the pars labyrinthica and fossa geniculata were also measured. The angle between the first and second parts of the Fallopian canal was estimated with different methods. The mean width of the tympanic part of the facial canal was found to be 1.79 mm on the right side and 1.67 mm on the left, the mean width of the mastoideal part was 1.8 mm on the right side and 1.7 mm on the left. Distances of the mastoideal part of the Fallopian canal to mastoideal cells, ear drum, sigmoid sinus and external surface of the temporal bone were also measured. Measurements of the sigmoid sinus, the bulb of internal jugular vein and the cavum musculi stapedii are included, too. The ranges found in our material are also given.  相似文献   

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