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排序方式: 共有695条查询结果,搜索用时 15 毫秒
1.
Lida Xing Martin G. Lockley Jianping Zhang Hendrik Klein Daqing Li Tetsuto Miyashita 《Historical Biology》2016,28(7):881-895
A dinosaur tracksite in the Lower Jurassic Ziliujing Formation of Sichuan Province, China consists of a spectacular sub-vertical exposure, with multiple track-bearing levels and trackways showing parallel and bimodal orientations. Based on well-preserved material, the new ichnogenus and ichnospecies, Liujianpus shunan ichnogen. nov. ichnosp. nov. is erected to accommodate distinctive sauropodomorph trackways occurring in this assemblage. Liujianpus has a unique combination of features, some relating to the early Jurassic basal sauropodomorph (prosauropod in traditional usage) ichnogenus Otozoum, others to the sauropod ichnogenus Brontopodus. Despite such a mix of basal sauropodomorph- and sauropod-like features, the trackmaker of Liujianpus is likely a basal sauropodomorph. This identification is consistent with the occurrence of basal sauropodomorph skeletons from geographically and chronologically close localities. The other distinct morphotype from the tracksite is linked to a sauropod trackmaker. As such, the ichnofauna consisting of two distinct foot morphotypes reflects the diversity of sauropodomorph dinosaurs in the Early Jurassic of Asia. 相似文献
2.
Recent collections from six sections in Lanongla area, Tethyan Himalaya allow the establishment of four buchia assemblages. In ascending order, they are Buchia-Buchia spitiensis, Buchia masquensis-Buchia rugasa, Buchia blanfordiana, Buchia piochii and Buchia subokensis assemblages. These Buchia assemblages first demonstrate that not only the Upper Jurassic strata but also the highest Buchia assemblage-Buchia subokensis, which appeared in Lower Cretaceous strata all over the world are present in Lanongla area. This first records the highest
Buchia assemblage in Lanongla area.
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Translated from Acta Scientiarum Naturalium Universitatis Pekinensis, 2005, 41 (4) [译自: 北京大学学报( 自然科学版), 2005,41(4)] 相似文献
3.
内蒙古道虎沟中侏罗世假古蝉属化石(同翅目,古蝉科) 总被引:4,自引:0,他引:4
描述古蝉科化石3新种,即多点假古蝉Pseudocossus punctulosus sp.nov.,美丽假古蝉P.bellus sp.nov.,弯脉假古蝉P.ancylivenius sp.nov..所有标本均采自内蒙古宁城道虎沟中侏罗世九龙山组,其中2个新种保存有完整的臀区.模式标本保存在首都师范大学生命科学学院. 相似文献
4.
In the framework of the palaeogeographical reconstruction of the Western Taurus during Jurassic, the study of northern and eastern boundary of the Taurids started. Detailed facies analysis evidenced the position of the Barla Dag ramp between two elevated areas: the southern rimmed shelf extension of the platform system and the northern neritic-beach-land plain. In the basal biostratigraphical and ecological characteristics of the Balcikhisar volcano-sedimentary sequence, correlated with the Fele outcrop, one genus and three new species of foraminifers have been found: Sievoides kocyigiti n. gen., n. sp. and Mesoendothyra altineriana n. sp. from neritic environment, and Kurnubia feleensis n. sp. from rimmed shelf lagoon. Both carbonate sedimentary deposits are intercalated with spilitic-basalt pillow lava flows. The age of the new three species is Kimmeridgian, controlled by some foraminifer golden hooks. 相似文献
5.
中国内蒙古中侏罗世脉翅目昆虫化石—新科(英文) 总被引:1,自引:0,他引:1
任东 《Entomologia Sinica》2002,(4)
建立脉翅目昆虫化石新科———Grammolingiidaefamnov .,并描述该科化石 3新属 6新种 :Grammolingiaboigen .nov .ofsp .nov .,Litholingiarhoragen .nov .ofsp .nov .,Litholingiaeumorphagen .nov .ofsp .nov .,Litholing iapolychotomagen .nov .ofsp .nov .,Leptolingiajurassicagen .nov .ofsp .nov .,Leptolingiatianyiensisgen .nov .etsp .nov ..给出了新科的属级检索表 ,描述的所有模式标本均采自于内蒙古自治区宁城县中侏罗世九龙山组地层中。标本分别保存在义县博物馆和首都师范大学生物系。本次发现再次表明目前关于脉翅目昆虫的认识仍然十分贫乏。 相似文献
6.
7.
Graciela Delvene 《Geobios》2003,36(5):519-531
The four sections richest in bivalves from the Middle and Upper Jurassic of the Iberian Range (Spain) were selected for a quantitative palaeoecological analysis of the bivalve fraction of the macrobenthos. Five bivalve associations and two assemblages were recognized with the help of a Q-mode hierarchical cluster analysis (Ward method). The main environmental factors controlling bivalve associations are thought to be substrate, water energy and distribution of organic matter. The bivalves exhibit a distinct spatial and temporal distribution pattern within the Aragonian Branch of the Iberian Range. Four of the bivalve associations occur in the Upper Oxfordian (Sot de Chera Fm) and one association in the Lower Callovian (Chelva Fm). In the Sot de Chera and Loriguilla formations, the abundance of bivalves decreases from NW to SE i.e., from relatively close to the shore line towards the distal-most part of the carbonate platform. In the Chelva Fm, bivalves are abundant in the Ariño region, interpreted as a palaeogeographic high. The spatial distribution of bivalves might have been largely controlled by the availability of nutrients. 相似文献
8.
Fossil wood collections at the Natural History Museum, London, were searched for the type material of two important species, described as early as 1831 by Witham, on the basis of material at least partly furnished by Nicol and collected in the Liassic of Whitby (Yorkshire, UK). The names given to these two species by Witham are the basionyms for more than ten other species names, while these species names also provide syntypes for several generic names. Despite this, the original material has been only rarely and partly revised, leading to much confusion.We managed to locate some of the original material. Several topotypes were also studied. On the basis of this review we propose here a neotypification for Peuce huttoniana Witham, a lectotypification for Cupressinoxylon barberi Seward and a lectotypification for Tiloxylon Hartig. We evidence several taxonomical and nomenclatural synonymies, assign Peuce lindleyana Witham to Protocedroxylon and P. huttoniana to Xenoxylon Gothan, and introduce the new combination Xenoxylon huttonianum (Witham) nov. comb. as the correct name for Xenoxylon ellipticum Gottwald & Holleis ex Schultze-Motel.A topotype of Araucariopitys americana Hollick & Jeffrey was also reviewed, which, together with previous results, leads us to suggest that Araucariopitys Hollick & Jeffrey, Protocedroxylon Gothan and Planoxylon Stopes should not be considered as taxonomical synonyms. This point is crucial to the interpretation of the fossil record of Early Abietinae. 相似文献
9.
Yongdong Wang Hong Zhang 《Proceedings. Biological sciences / The Royal Society》2010,277(1679):311-320
As a representative fossil member of the dipteridaceous fern, genus Hausmannia was reported worldwide from the Mesozoic strata; however, little is known about the fertile structures, including sporangia and in situ spores, of this genus. In this study, a new species Hausmannia sinensis was identified from the Middle Jurassic of Nei Mongol (Inner Mongolia), northern China. The specimens are compressions and are well preserved with details of sporangia and in situ spores. The leaf laminae are broadly fan-shaped, with an almost entire margin. Primary and lateral veins dichotomously branch to form square or polygonal meshes. Each ultimate mesh bears one to two circular sori of 0.4 mm in diameter. Sori are exindusiate; each sorus contains three to six round to ovoid sporangia. The annulus is developed and oblique, with stomial region present in proximal position. Spores are trilete, circular to oval in shape. Both proximal and distal surfaces are covered with baculate to subverrucate sculptures. Spores range from 20 to 30 μm in diameter (average 28 μm), and are comparable to the dispersed genera Baculatisporites Thomas and Pflug and Apiculatisporis Potonié and Kremp. Hausmannia sinensis represents the first compression species of genus Hausmannia form Eurasia, which shows the combination of well-preserved sori, sporangia, annuli and in situ spore characters, and is therefore helpful for further understanding the diversity and evolution of the Dipteridaceae fern lineage through time. 相似文献
10.
The question of the age of «Hauts de Meuse coral rag is studied again using new faunas of brachiopods and ammonites collected above, below and inside the coral rag. Ammonites fauna of the well known «Calcaires de Creuë is revised. Results obtained agree closely.The «Hauts de Meuse coral rag grew up during Middle Oxfordian time; and extend part of the Plicatilis zone (Antecedens Subzone) and the whole Transversarium Zone up to the basis of the Bifurcatus Zone, for the first time identified in Lorraine. So it span a short depositional time, about 1 MY, with a high deposition rate, the thickness of the coral rag being more than 100 meters, reaching 150 meters in Saint-Mihiel area. Towards SE, on the other side of the Marne Gap, the sudden change into basinal facies go with a reducing of thickness and deposition rate.Upper Oxfordian deposits show a relative uniformity of facies and thickness. At the top of Middle Oxfordian limestones, the age of the discontinuity and the Sequanian renewal of deposition is basal Bifurcatus Zone. Erosional renewal and terrigeneous deposits are a wide spread event by the beginning of Upper Oxfordian.In the paleontological part, species upon which are based new ages and interpretations are only figured, except the species new or with new paleontological data, which are described. Type specimen of Perisphinctes mosensisBayle, from the «Calcaires de Creuë, is described and photographically figured for the first time. 相似文献