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21.
An unusual occurrence in the upper Albian Toolebuc Formation of Queensland, Australia, of penetration of a guard of the belemnite Dimitobelus (Dimitobelus) stimulus into the disc of an indeterminate inoceramid bivalve, is the first report of this type of shell damage in the fossil record. The belemnite punctured completely both valves of the bivalve to the maximum diameter of the belemnite guard, by inferred compaction from sediment overburden during post-mortem biostratinomic processes. Shell thickening of the inoceramid bivalve by shearing of prismatic layers at the site of puncture indicates that the bivalve shell behaved plastically during the puncture and that the great flexibility of the prismatic layers was facilitated by the relatively thin shell and presence of organic sheaths around individual prisms. This flexibility may have been advantageous during a predatory attack, by allowing the maintenance of a seal during breakage of the shell margin.  相似文献   
22.
A new species of thiarid snail attributable to the extant genus Melanoides is described from the Early Cretaceous (middle-late Albian) non-marine deposits of the Griman Creek Formation at Lightning Ridge in northern New South Wales. It represents the oldest Australian record of the genus and the family. Implications for the palaeoecology and distribution of Australian Cretaceous non-marine gastropods are discussed.  相似文献   
23.
Thulborn, R.A., 2013. Lark Quarry revisited: a critique of methods used to identify a large dinosaurian track-maker in the Winton Formation (Albian–Cenomanian), western Queensland, Australia. Alcheringa, http://dx.doi.org/10.1080/03115518.2013.748482

A remarkable assemblage of dinosaur tracks in the Winton Formation (Albian–Cenomanian) at Lark Quarry, a site in western Queensland, Australia, has long been regarded as evidence of a dinosaurian stampede. However, one recently published study has claimed that existing interpretation of Lark Quarry is incorrect because the largest track-maker at the site was misidentified and could not have played a pivotal role in precipitating a stampede. That recent study has identified the largest track-maker as an ornithopod (bipedal plant-eating dinosaur) similar or identical to Muttaburrasaurus and not, as formerly supposed, a theropod (predaceous dinosaur) resembling Allosaurus. Those iconoclastic claims are examined here and are shown to be groundless: they are based partly on misconceptions and partly on fabricated data that have been assessed uncritically using quantitative measures of questionable significance. Such ill-founded claims do not reveal any substantial flaw in the existing interpretation of the Lark Quarry dinosaur tracks.  相似文献   
24.
Cai, C.-y. & Wang, B., 2013. The oldest silken fungus beetle from the Early Cretaceous of southern China (Coleoptera: Cryptophagidae: Atomariinae). Alcheringa 37, 1–4. ISSN 0311-5518

Atomaria cretacea sp. nov., a new silken fungus beetle, is described and figured based on an impression fossil from the Lower Cretaceous Shixi Formation at a locality near Qingxi Town, Jiangxi Province, southern China. The new species can be referred to the extant family Cryptophagidae as supported by the tiny body size, the clubbed antenna with dilated antennomere 1, closely spaced antennal insertions, and abdominal ventrite 1 being longer than the remaining ventrites. It is placed in the extant subfamily Atomariinae based on the presence of a frontoclypeal suture and the absence of gular sutures; and tentatively in Atomaria based on its body size, sub-parallel body shape, and the presence of a frontoclypeal suture.

Chen-Yang Cai [caichenyang1988@163.com], Bo Wang [savantwang@gmail.com], State Key Laboratory of Palaeobiology and Stratigraphy; Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, PR China. Received 11.11.2012; revised 26.1.2013; accepted 31.1.2013.  相似文献   
25.
O’Gorman, J.P., Salgado, L., Varela, J., & Parras, A., 2013. Elasmosaurs (Sauropterygia, Plesiosauria) from the La Colonia Formation (Campanian–Maastrichtian), Argentina. Alcheringa 37, 257–265. ISSN 0311-5518.

Elasmosaur postcranial remains from the La Colonia Formation (Campanian–Maastrichtian), Chubut Province, Patagonia, Argentina, are described. The new material has small dimensions and caudal vertebrae with parapophyses strongly projected laterally—characters shared with some Elasmosauridae indet. from the coeval Allen Formation, Río Negro Province, Argentina. These features reinforce the similarities between the plesiosaur faunas to the north and south of the Somún Curá Plateau. The small size of these elasmosaurs may be palaeoecologically related to the marginal marine depositional environment of the sedimentary host rocks.

José P. O’Gorman [joseogorman@fcnym.unlp.edu.ar], División Paleontología Vertebrados, Museo de La Plata, Universidad Nacional de La Plata, Paseo del Bosque s/n., B1900FWA, La Plata, Argentina and [CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas)]; Leonardo Salgado [salgadoleito@yahoo.com.ar], Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, Isidro Lobo y Belgrano, 8332 General Roca, Argentina and [CONICET]; Julio Varela [julioadrianvarela@hotmail.com], and Ana Parras [aparras@exactas.unlpam.edu.ar], INCITAP (CONICET-UNLPam), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina. Received 27.7.2012; revised 19.10.2012; accepted 27.10.2012.  相似文献   
26.
The Eumeralla and Wonthaggi formations (Otway and Strzelecki groups, respectively: late Hauterivian to Albian) of Victoria, Australia, have yielded diverse dinosaur faunas. Here we report a set of unassociated isolated specimens from these units including teeth, dorsal vertebrae, ribs and osteoderms of an indeterminate ankylosaurian dinosaur.  相似文献   
27.
Rich, T.H., Hopson, J.A., Gill, P.G., Trusler, P., Rogers-Davidson, S., Morton, S., Cifelli, R.L., Pickering, D., Kool, L., Siu, K., Burgmann, F.A., Senden, T., Evans, A.R., Wagstaff, B.E., Seegets-Villiers, D., Corfe, I.J., Flannery, T.F., Walker, K., Musser, A.M., Archer, M., Pian, R. & Vickers-Rich, P., June 2016. The mandible and dentition of the Early Cretaceous monotreme Teinolophos trusleri. Alcheringa 40, xx–xx. ISSN 0311-5518.

The monotreme Teinolophos trusleri Rich, Vickers-Rich, Constantine, Flannery, Kool & van Klaveren, 1999 Rich, T.H., Vickers-Rich, P., Constantine, A., Flannery, T.F., Kool, L. & van Klaveren, N., 1999. Early Cretaceous mammals from Flat Rocks, Victoria, Australia. Records of the Queen Victoria Museum and Art Gallery 106, 134. [Google Scholar] from the Early Cretaceous of Australia is redescribed and reinterpreted here in light of additional specimens of that species and compared with the exquisitely preserved Early Cretaceous mammals from Liaoning Province, China. Together, this material indicates that although T. trusleri lacked a rod of postdentary bones contacting the dentary, as occurs in non-mammalian cynodonts and basal mammaliaforms, it did not share the condition present in all living mammals, including monotremes, of having the three auditory ossicles, which directly connect the tympanic membrane to the fenestra ovalis, being freely suspended within the middle ear cavity. Rather, T. trusleri appears to have had an intermediate condition, present in some Early Cretaceous mammals from Liaoning, in which the postdentary bones cum ear ossicles retained a connection to a persisting Meckel’s cartilage although not to the dentary. Teinolophos thus indicates that the condition of freely suspended auditory ossicles was acquired independently in monotremes and therian mammals. Much of the anterior region of the lower jaw of Teinolophos is now known, along with an isolated upper ultimate premolar. The previously unknown anterior region of the jaw is elongated and delicate as in extant monotremes, but differs in having at least seven antemolar teeth, which are separated by distinct diastemata. The dental formula of the lower jaw of Teinolophos trusleri as now known is i2 c1 p4 m5. Both the deep lower jaw and the long-rooted upper premolar indicate that Teinolophos, unlike undoubted ornithorhynchids (including the extinct Obdurodon), lacked a bill.

Thomas H. Rich [], Sally Rogers-Davidson [], David Pickering [], Timothy F. Flannery [], Ken Walker [], Museum Victoria, PO Box 666, Melbourne, Victoria 3001, Australia; James A. Hopson [], Department of Organismal Biology & Anatomy, University of Chicago,1025 East 57th Street, Chicago, IL 60637, USA; Pamela G. Gill [], School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, U.K. and Earth Science Department, The Natural History Museum, Cromwell Road, London SW7 5BD, UK; Peter Trusler [], Lesley Kool [], Doris Seegets-Villiers [], Patricia Vickers-Rich [], School of Earth, Atmosphere and Environment, Monash University, Victoria 3800, Australia; Steve Morton [], Karen Siu [], School of Physics and Astronomy, Monash University, Victoria 3800, Australia; Richard L. Cifelli [] Sam Noble Oklahoma Museum of Natural History, University of Oklahoma, Norman, OK 73072, USA; Flame A. Burgmann [], Monash Centre for Electron Microscopy, 10 Innovation Walk, Monash University, Clayton, Victoria 3800, Australia; Tim Senden [], Department of Applied Mathematics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, Australian Capital Territory 0200, Australia; Alistair R. Evans [], School of Biological Sciences, Monash University, Victoria 3800, Australia; Barbara E. Wagstaff [], School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia; Ian J. Corfe [], Institute of Biotechnology, Viikinkaari 9, 00014, University of Helsinki, Finland; Anne M. Musser [], Australian Museum, 1 College Street, Sydney NSW 2010 Australia; Michael Archer [], School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia; Rebecca Pian [], Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192, USA. Received 7.4.2016; accepted 14.4.2016.  相似文献   
28.
AUTHOR, N. &; AUTHOR, P. December 2017. Article title. Alcheringa 42, 301-305. ISSN 0311-5518. Dysagrionidae are common in Paleogene sedimentary rocks, but rarely recorded in the Mesozoic. This family, however, is diverse in Burmese amber. A new dysagrionid damselfly, Palaeodysagrion youlini Zheng, Chang &; Chang sp. nov., is described here based on a well-preserved specimen (holotype) in Burmese amber. The new damselfly provides wing apex and body characters for Palaeodysagrion. It differs from Palaeodysagrion cretacia in having Arc slightly distal of Ax2, the midfork slightly basal of the nodus, Cr and Sn almost perpendicular to RA and RP and in having a simple wing system. This is the fourth dysagrionid damselfly described from the Burmese amber.

Daran Zheng* [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210,008, PR China; Su-Chin Chang []*, Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China; Bo Wang? [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210,008, PR China. *Also affiliated with: Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China. ?Also affiliated with: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100,101, PR China.  相似文献   
29.
Partially disarticulated shark vertebrae from the Lower Cretaceous Toolebuc Formation in central Queensland and the Bathurst Island Formation in the Northern Territory provide probable evidence of the Anacoracidae in Australia, and are possibly referable to Pseudocorax. Associated with large shark vertebrae from Canary Station, near Boulia, Queensland, are numerous placoid scales of four primary types which indicate a large pelagic shark. The Canary specimen is one of the few Mesozoic sharks known where scales have been found associated with vertebrae. Problems in referring the new shark material to the Anacoracidae and Pseudocorax are discussed. The significance of vertebral structure and scale morphology in Mesozoic shark evolution and ecology is examined. ‘Lamna daviesii’ Etheridge 1888 is considered a nomen dubium as vertebrae of this kind also occur in other genera in the Lamniformes, Orectolobiformes, and Carcharhinidae.  相似文献   
30.
CaramÉs, A., Martinez, M., Concheyro, A., RemÍrez, M. & Adamonis, S., 6 August 2019 2019. Holothuroidea: new records from the Lower Cretaceous of the Agrio Formation, Neuquén Basin, Argentina. An integrated study with foraminifers and calcareous nannofossils. Alcheringa XX, xx–xx. ISSN 0311-5518

New records of holothurian ossicles (Echinodermata) from the Lower Cretaceous Agrio Formation, Mendoza Group, in the northern Neuquén Basin, west-central Argentina, represent, excepting some general mention of ossicles, the first collection from the Lower Cretaceous of South America. The discovery is one of the few worldwide records of holothurian remains from this age. The analysed skeletal elements are associated with other microfauna and nannoflora retrieved from washed residues of claystones and marlstones of the lower strata of the Pilmatué Member, in Área 3000 and Puerta Curaco sections. The calcareous microfossil assemblage is composed almost exclusively of the foraminifera Epistomina loncochensis, suggesting quiet marine environments and low levels of dissolved oxygen in the bottom/water interface. A late Valanginian age is confirmed by the nannofossil assemblage found together with the holothurian ossicles. Analysis of ossicle shapes allows their attribution to molpadiids (Molpadida: Molpadiidae): one two-armed racquet-like single ossicle that remains as an indeterminate molpadiid and a new genus and species proposed for the abundant cross-shaped and star-shaped ossicles. The latter, owing to the presence of four holes and the lack of a spire or some elevation projecting well out from surface in the centre of the plates, resemble two known species of the genus Cruxopadia Reich, but they differ in their arm morphology.

Andrea Caramés [], IDEAN—Instituto de Estudios Geológicos Andinos ‘Don Pablo Groeber’, CONICET, Ciudad Universitaria Pabellón II, Intendente Güiraldes 2160-C1428EHA Buenos Aires, Argentina; Mariano Martinez [], Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, CONICET, A. Gallardo 470-C1405DJR Buenos Aires, Argentina; Andrea Concheyro [], IDEAN—Instituto de Estudios Geológicos Andinos ‘Don Pablo Groeber’, CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, Intendente Güiraldes 2160-C1428EHA Buenos Aires, Argentina, and Instituto Antártico Argentino, Argentina; Mariano Remírez [], CIG—Centro de Investigaciones Geológicas, CONICET, Universidad Nacional de La Plata, Diagonal 113 N° 275-B1904DPK, La Plata, Argentina; Susana Adamonis [], Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IDEAN. Ciudad Universitaria Pabellón II, Intendente Güiraldes 2160-C1428EHA Buenos Aires, Argentina.  相似文献   
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