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1.
Abstract

In the past, fossilised dinosaur eggshells have been extensively documented from the Upper Cretaceous Lameta Formation of Central India and as many as nine oospecies are known at present from this formation. Compared to this, only one dinosaur oospecies has been described from the Cretaceous succession of the Cauvery Basin. However, the first fossil egg from India, identified as a chelonian egg, was documented from the Aptian – Albian Karai Formation of the Cauvery Basin in 1957. Following this, a solitary titanosaurid dinosaur egg was described from the Upper Cretaceous (Lower Maastrichtian) Kallankuruchhi Formation, Cauvery Basin in 1996. More recently, we have recovered isolated eggshell fragments from the marine part of the Upper Cretaceous (Late Maastrichtian) Kallamedu Formation. Based on eggshell morphology, microstructure and ultrastructure, these eggshell fragments are assigned to the oospecies Fusioolithus baghensis. The new find from the Cauvery Basin is important from palaeobiogeographic point of view as the oofamily Fusioolithidae is found in the Upper Cretaceous strata of India, France, Argentina and Morocco. Based on the common occurrence of similar oospecies in South America, Africa, Europe and India, a Late Cretaceous palaeobiogeographic connection between India and South America as well as Europe via Africa is suggested.  相似文献   

2.
20世纪70至80年代,几乎所有关于江汉盆地跑马岗组和渔洋组的古生物文献都将其时代确定为晚白垩世。李伟同在深入地研究了跑马岗组标准剖面上的轮藻化石后提出跑马岗组大部分属于古新统。取自层位与跑马岗组相当的渔洋组上段上部的岩芯样品经分析后获得了丰富的孢粉化石。这一组合总的面貌与王大宁等获得的晚白垩世渔洋组的第三组合区别明显,而与古近纪的新沟嘴组的第四组合相似处很多。在该孢粉植物群中,常见于当地的晚白垩世分子,如希指蕨孢属、克拉梭粉属、江汉粉属、刺参粉属、鹰粉属等没有或极少见到。而在本组合常见的南岭粉属、五边粉属、漆树粉属等多出现在我国南方古新世地层中。因此,其时代很有可能为古新世。如果是这样,渔洋组上部有可能跨越了白垩系和古近系界线。从当前孢粉植物群含有很多亚热带成分以及麻黄粉属以及胡颓子粉属、忍冬粉属等看,它反映了江汉盆地当时偏干旱的亚热带气候。  相似文献   

3.
The trace fossil Sinusichnus sinuosus Gibert 1996 is described and interpreted as an open burrow system, attributed to a crustacean tracemaker, that shares some features with fodinichnial networks, such as Thalassinoides and Ophiomorpha , and with graphoglyptid burrows, such as Protopaleodictyon and Cosmorhaphe. These similarities suggest that Sinusichnus could have been produced by an animal combining deposit-feeding and farming (or trapping) strategies. The Sinusichnus record has yielded juvenile and adult burrows, often in close association. On account of minor morphologic differences between the two, juvenile tracemakers could have employed an agrichnial feeding strategy, whereas adults could have employed fodinichnial feeding.  相似文献   

4.
Abstract: A rich coral‐associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region. This discovery more than doubles the number of known fossil decapod species from Malta. The fossil bivalve Jouannetia (J.) semicaudata Des Moulins, 1830 and the extant decapod Maja goltziana D’Oliveira, 1888, are also recorded for the first time from Malta. Other Neogene coral‐associated decapod assemblages are investigated and correlated with the new assemblage from Malta. The migration of taxa between the Mediterranean region and the Paratethys, particularly during the Lower Badenian (Langhian), is evidenced by the strong affinity of the Maltese decapod assemblage with that of the Middle Miocene Badenian assemblages from Hungary, Poland and Ukraine. Upper Miocene, Messinian assemblages from Spain, Algeria and Morocco are also similar to that from Malta.  相似文献   

5.
About 200 Zoophycos specimens, including 90 specimens studied in detail, have been analysed in the continuous Upper Cretaceous–Lower Miocene pelagic sedimentary type sections of the Gubbio area (the Contessa Highway, Contessa Quarry and Bottaccione sections, Northern Apennines). The sediments are reddish to grey limestones and marls of the Scaglia Group and marls with volcaniclastic deposits of the Bisciaro Formation. The aim was to examine the evolutionary trend of what is probably the most debated trace fossil of all time, from the Upper Cretaceous to Lower Miocene. Despite having been found in beds ranging from the Cambrian to the present, no consensus has been reached regarding mode of construction, tracemaker or ethological explanation for Zoophycos. Four Zoophycos morphotypes are recognized at Gubbio showing variations of major and minor lamellae, apex, lobes and whorls: the Cretaceous–Eocene cone‐shaped type 1, the Upper Eocene–Middle Oligocene helicoidal type 2, the Oligocene lobate type 3 and the Upper Oligocene–Lower Miocene flat type 4. The very high ichnodensity in some beds (hundreds of specimens in discrete levels of the Bisciaro Formation, now destroyed by quarrying) seems to find explanation in abnormal concentrations of phytodetritus and organic matter on the seafloor in some periods. This very high abundance in discrete levels reflects a change in sedimentation and seafloor conditions at pre‐flysch deposition. Due to such high ichnodensity, many adjacent specimens display deformed outer margins. Taphonomic analysis shows a variation of whorls, laminae and U‐shaped lobes, reflecting ontogenetic development of the tracemaker(s) (?sipunculid worms).  相似文献   

6.
Abstract: Two species of decapod crustacean are recorded from the Agua de la Mula Member of the Agrio Formation (Upper Hauterivian – Lower Barremian) of the Neuquén Basin of west‐central Argentina, namely Astacodes falcifer Bell and a new species of Palaeohomarus, P. pacificus. The preservation of the specimens is exceptional, some showing delicate compound eyes and a stridulatory apparatus, features rarely found in fossil forms. Many specimens are preserved articulated inside calcareous nodules, within dark‐grey shales. The lobster‐bearing sediments accumulated in a low‐energy marine environment and diagenetic mineralization occurred very rapidly, prior to significant decay, thus allowing exceptional preservation of specimens. Palaeohomarus was a rare genus in the Cretaceous with a palaeogeographic distribution restricted to the Mediterranean Tethys, the eastern USA and Madagascar, while Astacodes falcifer has been recorded only from Speeton (eastern England) and Neuquén.  相似文献   

7.
开鲁盆地白垩系发育,至今已有200余口探井钻遇到上白垩统,其中嫩江组滨浅湖相沉积地层厚度稳定,分布广泛,含较丰富的孢粉化石。通过对嫩江组孢粉化石的系统研究,建立了以Schizaeoisporites-BeaupreaiditesLythraites为代表的孢粉组合。孢粉组合和岩石组合的对比表明,开鲁盆地缺失松辽盆地嫩江组中上部地层。根据沉积特征和孢粉植物群面貌,对古植被、古气候和古环境进行了讨论,认为本区晚白垩世处于东北中生孢粉植物区南缘,孢粉植物群具有过渡性质,反应了偏干的暖温带—亚热带气候特征。  相似文献   

8.
岩石组合特征和同位素数据表明,松辽盆地来D13井137.0—142.0m井段属于早白垩世晚期(Aptian—Albian期)营城组。104.2—137.0m井段光山核桃粉(Caryapollenites simplex)-拟榛莫米粉(Momipites coryloides)-朴粉未定种(Celtispollenites sp.)-具缘铁杉粉(Tsugaepollenites igniculus)组合特征可以与前人的大安组孢粉组合特征对比,反映的都是暖温带至北亚热带中生气候,而与晚白垩世嫩江组的孢粉组合特征截然不同,应该确定为早中新世晚期至中中新世的大安组。54.2—104.2m井段小蒿粉(Artemisiaepollenites minor)-拟桦粉未定种(Betulaceoipollenites sp.)-枥粉未定种(Carpinipites sp.)-水龙骨单缝孢未定种(Polypodiaceaesporites sp.)组合特征可以与前人的泰康组孢粉组合特征对比,反映的都是暖温带至北亚热带中生偏旱气候,这与前人依据岩石组合特征确定为泰康组的结论一致,孢粉组合时代分析表明,该井段沉积的时间为晚中新世至上新世初期。研究结果丰富了松辽盆地新近纪孢粉地层学内容,为松辽盆地西部斜坡区井下新近纪孢粉地层学对比提供了新资料,也为邻区新近纪生物地层学对比以及古植被和古气候分析提供了新的依据。  相似文献   

9.
Abstract: The Lower Cretaceous rocks of South Australia have yielded a diverse marine reptile assemblage of up to five families of plesiosaur (including a new cryptoclidid or cimoliasaurid, indeterminate elasmosaurids, a possible polycotylid, rhomaleosaurids, and pliosaurid) and one family of ichthyosaur (ophthalmosaurid). Other common associated vertebrates include chimaerids and osteichthyans. Sharks, dipnoans and dinosaurs are uncommon and marine turtles are notably absent. The main fossil‐producing strata belong to the Lower Aptian–Lower Albian Bulldog Shale although the Upper Albian Oodnadatta Formation has produced isolated elements. Both these units comprise finely laminated shaly mudstones and claystones deposited in a transgressive shallow coastal, epicontinental marine environment. Estimates of palaeolatitude place South Australia between 60° and 70°S, in the late Early Cretaceous. Sedimentary structures (including lonestone boulders and glendonites), fossils, isotope data and climatic modelling also indicate that seasonally cool–cold conditions (possibly with winter freezing) prevailed during deposition of the Bulldog Shale. This contrasts markedly with climate regimes typically tolerated by modern aquatic reptiles but suggests that some of the South Australian Mesozoic taxa may have possessed adaptations (including elevated metabolic levels and/or annual migration) to cope with low temperatures. A high proportion of juvenile plesiosaur remains in the Bulldog Shale might also indicate that nutrient‐rich cold‐water coastal habitats functioned as both ‘safe calving grounds’ and refuges for young animals prior to their entering the open sea as adults. The occurrence of plesiosaurs and ichthyosaurs in the high‐latitude Lower Cretaceous of southern Australia, along with plesiosaurs and mosasaurs in the Upper Cretaceous of South America, Antarctica, New Zealand and the Chatham Islands, demonstrates that Mesozoic marine reptiles utilized southern high‐latitude environments over a considerable period of time, and that these records do not represent casual occupation by isolated taxa.  相似文献   

10.
Late Cretaceous strata of the Western Tarim Basin, Southern Xinjiang, China are divided into the Kukebai, Wuyitake. Yigeziya and Tuyilouk Formations. The gastropod faunas can be arranged into six communities corresponding to broad depositional environments. Two communities commonly occur in the nearshore shoal environments: the Vernedia pusillina Community from the Lower Member of the Kukebai Formation and the Trochactaeon (Neocylindrites)-Actaeonella Community from the Lower Member of the Yigeziya Formation. Three communities occur in the shelf environments: these are the Helicaulax and Ascensovoluta-Gyrodes Communities of the lower and upper parts of the Upper Member of the Kukebai Formation respectively and the Ampullina-Cantharus Community of the Middle-Upper Member of the Yigeziya Formation. A hypersaline environment is indicated by the Haustator-Corbula Community from the Middle Member of the Kukebai Formation.  相似文献   

11.
新疆北部侏罗、白垩纪非海相腹足类   总被引:1,自引:0,他引:1  
朱祥根 《古生物学报》1994,33(1):85-105
记述新疆准噶尔盆地和吐鲁番盆地侏罗、白垩纪非海相腹足类10属15种,其中6新种、1未定种。根据这些腹足类的地层分布特点将它们划分为3个组合,自下而上为1)Viviparussangongheensis组合,时代为早侏罗世;2)Viviparusqiketaiensis-Amplovalvatasuturalis组合,时代为中侏罗世;3)Cincinnaturgensis组合,时代为早白垩世。对这些腹足类生活习性的分析,这两个盆地在早侏罗世气候温暖湿润,草木繁茂,大部分地区为平静、滞流的湖泊、沼泽;中侏罗世盆地相对下陷,水域扩大加深;中侏罗世末期至晚侏罗世早期,盆地抬升,水域范围明显缩小;至早白垩世,盆地又扩大加深。  相似文献   

12.
A new ichnotaxon is recognized in the Hidden Lake Formation, Upper Cretaceous of James Ross Island, Antarctica. Fuersichnus striatus consists of horizontal to subhorizontal, isolated or loosely clustered, U‐shaped, curved to banana‐like burrows, characterized by distinctive striations parallel to the trace axis. It is interpreted as a dwelling structure probably produced by crustaceans or polychaetes. This recording of Fuersichnus extends its stratigraphic range from the Triassic‐Jurassic to the Cretaceous and its environmental setting from nonmarine to marine environments. F. striatus typified consolidated, but unlithified substrates. Accordingly, it must be considered a member of the Glossifungites ichnofacies.  相似文献   

13.
Fossil plants from the lower part of Xianshuihe Formation in the Lanzhou Basin, Gansu Province were studied. The flora contains 29 species, representing 20 genera and 12 families, which include Lauraceae ( Daphnogene ), Lardizabalaceae ( Akebia ), Berberidaceae ( Berberis ), Ulmaceae ( Planera, Ulmus, Zelkova ), Betulaceae ( Alnus, Carpinus ), Myricaceae( Myrica ), Salicaceae ( Populus, Salix), Myrsinaceae(Ardisia), Rosaceae ( Prunus, Sorbus, Sorbaria, Spiraea ), Leguminosae ( Gleditsia, Sophora), Anacardiaceae (Rhus), Caprifoliaceae(Viburnum). An analysis of the floristic elements and their foliar physiognomy shows that most members of the flora are deciduous broad-leaved trees or shrubs with a few evergreen shrubs. The most noteworthy species is Rhus turcomanica which was present in the Middle Eocene to Late Eocene of Central Asia (Kazakhstan, Turkmenistan). Generally, Rhus turcomanica occurred at the same beds as Palibinia, an extinct fossil plant whose presence indicates a subtropical dry climate. Another species, Sorbaria callicomifolia Kornilova was present from the Early Oligocene to Early Miocene of Central Asia (Kazakhstan and Turkmenistan). According to an analysis of spores and pollen, this flora contains over 20 species. It is predominated by the angiosperm pollen. There appeared Ephedripites and Nitrariadites which were important elements in the dry area. Ephedripites was found from the Upper Cretaceous to Early Tertiary. Nitrariadites occurred in the Late Miocene, whereas Rhus turcomanica and Sorbaria callicomifolia were both reported in the subtropical dry area from the Middle Eocene to Early Oligocene. The latest record of Rhus turcomanica is from the Middle Eocene to Early Oligocene of Central Asia. The presence of this element in the lower part of Xianshuihe Formation may indicate that itsage is the latest stage of the Early Oligocene.  相似文献   

14.
兰州盆地早第三纪植物及古气候意义   总被引:10,自引:0,他引:10  
化石采自甘肃省兰州盆地咸水河组底部,经研究认为有29种,归属20属12科。它们是:樟科 Lauraceae (Daphnogene),木通科Lardizabalaceae(Akebia),小檗科Berberidaceae(Berberis),榆科Ulmaceae (Planera,Ulmus,Zelkova),桦木科Betulaceae(Alnus,Carpinus),杨梅科Myricaceae(Myrica),杨柳科Sali- caceae(Populus,Salix),紫金牛科Myrsinacese(Ardisia),蔷薇科Rosaceae (Prunus,Sorbus,Sorbaria,Spir- aea),豆科Leguminosae(Gleditsia,Sophora),漆树科 Anacardiaceae(Rhus),忍冬科Caprifoliaceae(Viburnum) 等。经植物区系组成与叶相分析显示,该植物区系的大多数成员是落叶阔叶乔、灌木,少数为常绿灌木。其中特殊的分子是 Rhus turcomanica Korov.ex Vassilvesk,该成分是早第三纪中、晚期的标志化石植物。另一化石植物 Sorbaria callicomifolia Kornilova曾出现在中亚的早渐新世,最晚至早中新世。同一层位采集的孢粉样分析结果显示:该组合仅约20种,种类相对贫乏,并以被子植物的花粉占优势。其中出现裸子植物的麻黄粉,被子植物的白刺粉及蒿粉等,这几个类型均指示沉积时期经历干旱气候。综合植物大化石及孢粉分析研究,均出现一些指示气候为亚热带干旱或周期性干旱气候的特点,并据Rhus turcomanica出现的最晚记录,推测咸水河组底部的地质时代大约是早渐新世晚期。  相似文献   

15.
A rich variety of vertebrate footprints is known from a number of Upper Eocene to Lower Miocene localities of Navarre (western Pyrenees). The sediments were deposited in a wide range of depositional environments, from marginal marine to diversified terrestrial. Abundant bird tracks have been found in the coastal deposits of the Upper Eocene Liedena Sandstone of the Yesa and Itzagaondoa areas. Ciconiiformes-like (Leptoptilostipus pyrenaicus) and Charadriiformes-like (Charadriipeda ichnospp.) footprints have been recognized. Mammal ichnites have been discovered in the Oligocene and Lower Miocene deposits of Navarre. Equoid perissodactyl ichnites similar to those of Plagiolophustipus occur in the Oligocene fluviatile rocks of the Mués Sandstone of Olexoa and the Rocaforte Sandstone near Oibar and Sada. Trackways of entelodontids (Entelodontipus) are known in fluviatile-palustrine beds of the Oligocene Mués Sandstone of Olkotz. Additionally, bird (Charadriiformes-like) tracks are known in fluviatile-palustrine floodplain deposits of the Lower Miocene Ujué Formation of Los Arcos. In the same area, the Desoio and Los Arcos outcrops have also yielded perissodactyl trackways of possible Equoidea. Trackways of rhinocerotids (?) and artiodactyls (possibly Pecoripeda) are described from the Lower Miocene (Ramblian) palustrine limestones marginal to the Lerín Formation of Kaparroso and from alluvial fan deposits of the Uncastillo-Perdón Formation of Altzorritz, respectively.  相似文献   

16.
Cetacean remains from two different stratigraphic units exposed in Falcon State, northwestern Venezuela, are described. The first record is derived from the Lower Miocene Cantaure Formation and the second from the Lower Pliocene Punta Gavilán Formation, The two specimens are identified as an indeterminate species of a platanistoid Squalodelphinidae, and an indeterminate cetothere or balaenopterid, respectively.   相似文献   

17.
The Upper Cretaceous Coon Creek Lagerstätte of Tennessee, USA, is known for its extremely well‐preserved mollusks and decapod crustaceans. However, the depositional environment of this unit, particularly its distance to the shoreline, has long been equivocal. To better constrain the coastal proximity of the Coon Creek Formation, we carried out a multiproxy geochemical analysis of fossil decapod (crab, mud shrimp) cuticle and associated sediment from the type section. Elemental analysis and Raman spectroscopy confirmed the presence of kerogenized carbon in the crabs and mud shrimp; carbon isotope (δ13C) analysis of bulk decapod cuticle yielded similar mean δ13C values for both taxa (?25.1‰ and ?26‰, respectively). Sedimentary biomarkers were composed of n‐alkanes from C16 to C36, with the short‐chain n‐alkanes dominating, as well as other biomarkers (pristane, phytane, hopanes). Raman spectra and biomarker thermal maturity indices suggest that the Coon Creek Formation sediments are immature, which supports retention of unaltered, biogenic isotopic signals in the fossil organic carbon remains. Using our isotopic results and published calcium carbonate δ13C values, we modeled carbon isotope values of carbon sources in the Coon Creek Formation, including potential marine (phytoplankton) and terrestrial (plant) dietary sources. Coon Creek Formation decapod δ13C values fall closer to those estimated for terrigenous plants than marine phytoplankton, indicating that these organisms were feeding primarily on terrigenous organic matter. From this model, we infer that the Coon Creek Formation experienced significant terrigenous organic matter input via a freshwater source and thus was deposited in a shallow, nearshore marine environment proximal to the shoreline. This study helps refine the paleoecology of nearshore settings in the Mississippi Embayment during the global climatic shift in the late Campanian–early Maastrichtian and demonstrates for the first time that organic δ13C signatures in exceptionally preserved fossil marine arthropods are a viable proxy for use in paleoenvironmental reconstructions.  相似文献   

18.
We describe the new agglutinated foraminiferal genus and species Rectogerochammina eugubina nov. gen., nov. sp. from the Upper Cretaceous Scaglia Rossa Formation of the Umbria-Marche Basin in Italy. The genus differs from Gerochammina (Neagu, 1990) in the presence of a terminal uniserial part.  相似文献   

19.
浙江天台盆地上白垩统赤城山组长形蛋科一新蛋属   总被引:2,自引:0,他引:2  
浙江天台盆地上白垩统赤城山组发现一新的恐龙蛋类型。依据蛋化石形态、大小和蛋壳柱状层生长纹呈波浪形等特征,将其归入长形蛋科(Elongatoolithidae)。这枚恐龙蛋的蛋壳外表面具网状纹饰,蛋壳锥体层与柱状层界线明显,二者厚度之比近1:2,气孔道细而直,这些特征区别于其他长形蛋科的成员,因此,建立一新的蛋属、蛋种:网纹副长形蛋(Paraelonga-toolithus reticulatus oogen.et oosp.nov.),代表晚白垩世早期长形蛋科的新成员。  相似文献   

20.
《Palaeoworld》2014,23(2):187-199
Deposits from the Ordos Basin of mid-western China are rich in body fossils and ichnofossils of Early Cretaceous vertebrates. Thousands of Early Cretaceous sauropod, theropod and bird tracks described since 1958 have been found at several localities in the basin. We report two new sites (Dijiaping and Bawangzhuang) in the Luohe Formation of the Ordos Basin, Shaanxi Province, which contain small theropod footprints that are here referred to the ichnogenus Jialingpus. The assignment is based on pad configurations including (1) the large metatarsophalangeal area positioned in line with the axis of digit III, (2) the subdivision of this part into a small pad behind digit II, which in some specimens is close to the general position of the hallux (digit I), and a large metatarsophalangeal pad behind digit IV, and (3) a distinct inter-pad space between metatarsophalangeal pads and proximal phalangeal pads of digits II and III. We re-describe the type material of the type ichnospecies Jialingpus yuechiensis from the Upper Jurassic Penglaizhen Formation of Sichuan Province, proposing a largely amended diagnosis for this ichnotaxon. The presence of a digit I trace in the holotype, indicating a relatively long hallux, and the large metatarsophalangeal area positioned in line with digit III distinguishes Jialingpus from the ichnogenus Grallator and similar tracks that all lack these features. The only difference between Jialingpus specimens from the Cretaceous of the Ordos Basin and those of the Jurassic Penglaizhen Formation is the larger digit divarication in the Cretaceous taxon. This is the fourth record of Jialingpus in China and the second in Cretaceous strata, with the first being those from the Huangyangquan locality in Xinjiang, China.  相似文献   

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