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21.
Benson, R.B.J., Fitzgerald, E.M.G., Rich, T.H. & Vickers-Rich, P., 2013. Large freshwater plesiosaurian from the Cretaceous (Aptian) of Australia. Alcheringa 37, 1–6. ISSN 0311-5518

We report a large plesiosaurian tooth from the freshwater early–middle Aptian (Early Cretaceous) Eumeralla Formation of Victoria, Australia. This, combined with records of smaller plesiosaurian teeth with an alternative morphology, provides evidence for a multitaxic freshwater plesiosaurian assemblage. Dental and body size differences suggest ecological partitioning of sympatric freshwater plesiosaurians analogous to that in modern freshwater odontocete cetaceans. The evolutionarily plastic body plan of Plesiosauria may have facilitated niche differentiation and helped them to exclude ichthyosaurs from freshwater environments during the Mesozoic. However, confirmation of this hypothesis requires the discovery of more complete remains.

Roger B.J. Benson [roger.benson@earth.ox.ac.uk], Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK; Erich M.G. Fitzgerald [efitzgerald@museum.vic.gov.au], Thomas H. Rich [trich@museum.vic.gov.au], Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia; Thomas H. Rich and Patricia Vickers-Rich [pat.rich@monash.edu], School of Geosciences, Monash University, Clayton, Victoria 3800, Australia. Received 30.10.2012; revised 27.1.2013; accepted 31.1.2013.  相似文献   
22.
23.
Yuan, D.X., Zhang, Y.C., Zhang, Y.J., Zhu, T.X. & Shen, S.Z., 2014. First records of Wuchiapingian (Late Permian) conodonts in the Xainza area, Lhasa Block, Tibet, and their palaeobiogeographic implications. Alcheringa 38, 546–556. ISSN 0311-5518.

Conodonts are among the best fossil groups to provide high-resolution biostratigraphic correlation and resolve the palaeobiogeographic evolution of the Permian. However, they have been rarely reported from the Lhasa Block in Tibet. Here we report the first discovery of Wuchiapingian (early Lopingian) conodonts from the Xiala Formation in the Lhasa Block, Tibet. This conodont fauna includes two genera and three species (Clarkina liangshanensis, C. orientalis, Iranognathus sp.). The conodont fauna indicates that the Xiala Formation previously assigned to the Guadalupian actually ranges from late Kungurian to late Wuchiapingian. The existence of the late Wuchiapingian conodont species Clarkina orientalis and C. liangshanensis in the Lhasa Block provides additional data to support the viewpoint that this block probably had been in a warm-water regime during the Wuchiapingian (Lopingian).

Dong-Xun Yuan [], School of Earth Sciences and Engineering, Nanjing University, 22 Hankou Road, Nanjing, 210093, PR China and State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing, 210008, PR China; Yi-Chun Zhang [] and Shu-Zhong Shen [] (corresponding author), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing, 210008, PR China; Yu-Jie Zhang [] and Tong-Xing Zhu [], Chengdu Center, China Geological Survey, 2 Renming Road North, Chengdu, 610081, PR China. Received 9.1.2014; revised 1.4.2014; accepted 28.4.2014.  相似文献   
24.
Marsola, J.C.A., Grellet-Tinner, G., Montefeltro, F.C., Sayão, J.M., Hsiou, A.S. & Langer, M.C., 2014. The first fossil avian egg from Brazil. Alcheringa 38, 563–567. ISSN 0311-5518.

In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4?×?19.5?mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Formation (Río Colorado Subgroup) of Argentina advocates affinity with basal Ornithothoraces. Furthermore, coherency of their depositional contexts might imply a compatible preference for breeding and nesting environments.

Júlio Cesar de A. Marsola [], Annie Schmaltz Hsiou [] and Max C. Langer [], Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, São Paulo state, 14040-901, Brazil. Gerald Grellet-Tinner [], Centro Regional de Investigaciones La Rioja—Consejo Nacional de Investigaciones Científicas y Técnicas, Entre Ríos y Mendoza s/n, 5301 Anillaco, Argentina; Orcas Island Museum, PO Box 134, 181 North Beach Road, Eastsound, WA 98245. Felipe C. Montefeltro [], Departamento de Zoologia, Universidade Estadual Paulista, Avenida 24A 1515, Rio Claro, São Paulo State, 13506-900, Brazil. Juliana M. Sayão [], Laboratório de Diversidade do Nordeste, Núcleo de Biologia, Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Rua do Alto do Reservatório s/n, Bela Vista, Vitória de Santo Antão, Pernambuco state, 52050-480, Brazil. Received 18.12.2013; revised 30.4.2014; accepted 18.5.2014.  相似文献   
25.
The first Miocene records of silicified fossil woods from the Mariño Formation, Potrerillos area, Andes Precordillera, Mendoza province, Argentina are described. Rhaphithamnoxylon artabeae gen. et sp. nov. is described as the first fossil wood referable to Verbenaceae from Argentina. This new fossil species is related to extant Rhaphithamnus Miers, sharing the following anatomical features: diffuse porosity, distinct growth ring boundaries, numerous small to very small vessels, commonly in radial multiples, 1–3 seriate rays, and heterocellular and scarce paratracheal axial parenchyma. Rhaphithamnus contains only two extant species: R. spinosus (A.L. Juss.) Moldenke, which occurs in the Valdivian forests of Chile and Argentina, and R. venustus (Philippi) Robinson, which is endemic to the Juan Fernández Islands. Representatives of Verbenaceae are distributed predominantly in the Americas from Patagonia (Argentina) to Canada, and they are inferred to have originated in South America. The fossil wood described herein provides new age and geographical constraints on the raphithanoid lineage within Verbenaceae. Other fossil woods recorded from the Mariño level are retained under open nomenclature, as they possess a combination of mostly solitary broad vessels, and smaller vessels in radial multiples or in clusters, with numerous, vasicentric to confluent axial parenchyma, and heterocellular, high rays. Thus, they have features akin to dicotyledonous lianas or vine-like or small shrub species.  相似文献   
26.
The isolated scapula of a chelonioid sea turtle is described from the Upper Cretaceous (upper Maastrichtian) Miria Formation of the Giralia Ranges in Western Australia. Character states including the wide angle of divergence between the scapular processes (possibly reaching 140°), projection of the glenoid on a constricted scapular neck, and highly vascular glenoid articular surfaces suggest affinity with dermochelyoids—the most diverse and geographically widespread clade of Mesozoic chelonioids. The Miria Formation chelonioid scapula constitutes the first definitive record of a Late Cretaceous sea turtle from Australia and is one of the few occurrences thus far documented from Upper Cretaceous–Paleogene deposits in the Southern Hemisphere.  相似文献   
27.
Comparisons of conodont and trilobite communities from the Arenig-Llanvirn of northern Spitsbergen show that both groups were influenced by the same environmental factors, related to a shallow to deep water profile at the western edge of the proto-Atlantic Ocean (Iapetus). The majority of both conodonts and trilobites had benthic or nektobenthic habits; a few genera of both groups were pelagic. Temperature was a major influence on the distribution of conodonts; similar genera could occur on both sides of ancient oceans (e.g. Iapetus) given the same temperature regime.  相似文献   
28.
Disc-like galls are reported on the Triassic corystosperm leaf Dicroidium hughesii (Feistmantel) Lele from the Parsora Formation of South Rewa Gondwana Basin, central India. Although there have been numerous reports of arthropod–plant interactions from Permian and Lower Cretaceous successions, this is the first unequivocal report of arthropod–plant interactions from the Triassic succession of Peninsular India. The new record adds to global evidence that arthropod herbivory and gall formation, in particular, had rediversified by the Late Triassic in the wake of the end-Permian mass extinction.  相似文献   
29.
苏秉琦在1992年9月以后,对燕山南北地区文明发展较早而衰败亦较早的原因、传说的五帝时代事迹的地域与中原地区的古国、对"五胡乱华"的历史意义等问题,又作了进一步的探索;并结合对恩格斯在《家庭、私有制和国家的起源》一书中分析的国家起源的三种模式的思考,于1993年11月形成了中国国家发展模式的三种类型(北方原生型、中原次生型、北方草原续生型)的认识,于1994年1月写成《国家起源与民族文化传统(提纲)》一文,标志着苏秉琦学术体系的形成。其中,红山文化后期进入古国阶段、是否确认良渚文化已进入方国这两个问题尚待研究证实。苏秉琦学术体系的形成,以及围绕这些学术弘论的产生而展开的各种探索与研究过程本身,是1986年以来探索中国文明起源所取得的最重大的学术研究成果。  相似文献   
30.
SHI, C.F., WANG, Y.J., YANG, Q. & REN, D., September 2012. Chorilingia (Neuroptera: Grammolingiidae): a new genus of lacewings with four species from the Middle Jurassic of Inner Mongolia, China. Alcheringa 36, 311–320. ISSN 0311-5518.

A new grammolingiid genus, Chorilingia containing four new species (C. euryptera, C. parvica, C. translucida and C. peregrina) is described and illustrated from the Jiulongshan Formation at Daohugou, Inner Mongolia, China. The new genus is differentiated mainly on the first branch of vein Rs (Rs1) separating distal to the forks of both CuA and CuP. A key to species of the genus is provided.  相似文献   
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