Late Devensian environments in the Vale of Mowbray, North Yorkshire, UK: evidence from palynology

Two radiocarbon-dated Lateglacial pollen diagrams from the Vale of Mowbray (northern Vale of York) are presented from sites in the lowlands between the washlands courses of the rivers Swale and Ure in North Yorkshire, an area with little previous palynological research despite its proximity to the Devensian glacial advance limits in eastern England. The profiles, from Snape Mires and Nosterfield, include the Loch Lomond Stadial (Younger Dryas) and the Holocene transition, while that from Snape Mires also includes the period from the early part of the Lateglacial Interstadial. This profile differs from most published Interstadial diagrams from the Yorkshire region in having a long-delayed expansion of tree and shrub taxa. Juniperus (juniper) remains important after vegetation development takes place and the pollen record includes evidence of two cold climate oscillations before the maximum development of Betula (birch) woodland near the end of the Lateglacial Interstadial. At both profiles Artemisia (mugwort) frequencies are lower during the Loch Lomond Stadial than at many regional sites, probably due to edaphic factors in these lowland locations. The two sites provide valuable environmental data that enable comparison between the more wooded Lateglacial vegetation to the south in the Vale of York and Humberside and the more open contemporaneous vegetation to the north in the Durham and Northumberland lowlands.     

A reappraisal of a putative record of abelisauroid theropod dinosaur from the Middle Jurassic of England

Abelisauroidea are a recently recognized clade of theropod dinosaurs that have a predominantly Gondwanan distribution. Recently, a distal theropod tibia from the Middle Jurassic of England was identified as an abelisauroid, representing one of the oldest records of the group in general and the only Jurassic occurrence in Europe. On this basis, rapid radiation of abelisauroid and a global distribution of this clade in the Jurassic were suggested. Here, the specimen in question is re-examined and the characters used for referral to the Abelisauroidea are re-evaluated. None of the proposed characters can be demonstrated to represent abelisauroid synapomorphies and all have a wider distribution; especially coelurosaurian theropods, which are known from contemporaneous beds in England, frequently show the same character combination. Thus, there is currently no secure evidence for the occurrence of abelisauroids in the Jurassic of the northern Hemisphere, and the early evolution of this clade remains poorly known. Furthermore, other fragmentarily known taxa previously referred to Abelisauroidea based on putative synapomorphies of the distal tibia, such as Ozraptor and Austrocheirus, should be considered as Theropoda indet.     

Intact theropod dinosaur eggs with embryonic remains from the Late Cretaceous of southern China

In spite of tremendous discoveries of dinosaur eggs and nests over the world, dinosaur embryonic remains are rare. Until today, dinosaur embryos associated with eggshells are only known in about 20 cases, most of which were recovered from broken or crushed eggs. Here we report intact dinosaur eggs in a partial clutch with preserved embryonic remains in eggs from the Upper Cretaceous Nanxiong Formation of Ganzhou in the southern Jiangxi Province of China. Based on macro- and microscopic features of eggs and eggshells, these eggs were identified as Elongatoolithus sp., and possibly belong to oviraptorosaurs. A CT scanning topography revealed that all the eggs contain accumulations of embryonic bones, including possible femur and tibia. Our discovery suggests that dinosaur embryos might be preserved more than we have recognized, because intact eggs potentially confine embryonic remains.     

河北赤城地区土城子组中一例极可能的兽脚类恐龙蹲伏迹(英文)

描述了河北省赤城县寺梁山土城子(后城)组一例极可能的兽脚类恐龙蹲伏迹及相关的足迹,该蹲伏迹也是该组地层目前发现的最大的兽脚类足迹。虽然缺乏前足迹和尾迹,但因保存了左跖骨印、关联的坐骨及可能的耻骨胼胝印被定为蹲伏迹。该蹲伏迹是世界上第三例非对称的兽脚类恐龙蹲伏迹。     

A ceratopsian dinosaur from the Late Cretaceous of eastern North America,and implications for dinosaur biogeography

Tyrannosaurs and hadrosaurs from the Late Cretaceous of eastern North America (Appalachia) are distinct from those found in western North America (Laramidia), suggesting that eastern North America was isolated during the Late Cretaceous. However, the Late Cretaceous fauna of Appalachia remains poorly known. Here, a partial maxilla from the Campanian Tar Heel Formation (Black Creek Group) of North Carolina is shown to represent the first ceratopsian from the Late Cretaceous of eastern North America. The specimen has short alveolar slots, a ventrally projected toothrow, a long dentigerous process overlapped by the ectopterygoid, and a toothrow that curves laterally, a combination of characters unique to the Leptoceratopsidae. The maxilla has a uniquely long, slender and downcurved posterior dentigerous process, suggesting a specialized feeding strategy. The presence of a highly specialized ceratopsian in eastern North America supports the hypothesis that Appalachia underwent an extended period of isolation during the Late Cretaceous, leading the evolution of a distinct dinosaur fauna dominated by basal tyrannosauroids, basal hadrosaurs, ornithimimosaurs, nodosaurs, and leptoceratopsids. Appalachian vertebrate communities are most similar to those of Laramidia. However some taxa-including leptoceratopsids-are also shared with western Europe, raising the possibility of a Late Cretaceous dispersal route connecting Appalachia and Europe.     

河北赤城地区土城子组中一例极可能的兽脚类恐龙蹲伏迹

描述了河北省赤城县寺梁山土城子（后城）组一例极可能的兽脚类恐龙蹲伏迹及相关的足迹,该蹲伏迹也是该组地层目前发现的最大的兽脚类足迹。虽然缺乏前足迹和尾迹。但因保存了左跖骨印、关联的坐骨及可能的耻骨胼胝印被定为蹲伏迹。该蹲伏迹是世界上第三例非对称的兽脚类恐龙蹲伏迹。     

河南西峡盆地恐龙蛋化石及略论恐龙绝灭问题

西峡盆地晚白垩世红色陆相碎屑岩系地层中(包括高沟组、马家村组、寺沟组),产有类型多、数量大、成窝性好的恐龙蛋化石。已发现有7科8属10种。自下而上,恐龙蛋的种类、数量、含蛋层数、蛋窝均大幅度地减少,由高沟组内5科67种,约10层含蛋层,至寺沟组内仅存1科1属2种,含蛋层为2层。恐龙绝灭原因的研究,已有30种以上的学说或观点,但这些观点都不能圆满地解释恐龙的绝灭问题。恐龙的绝灭应该是多因素的,既有地外的灾变,又有地内,生物本身生理的因素。在内、外因等诸因素的共同作用下,恐龙才有可能绝灭。     

A new, large tyrannosaurine theropod from the Upper Cretaceous of China

Tyrannosaurids are primarily gigantic, predatory theropod dinosaurs of the Cretaceous. Here we report a new member of the tyrannosaurid clade Tyrannosaurinae from the Upper Cretaceous Wangshi Group of Zhucheng, Shandong Province, China, based on a maxilla and associated dentary. The discovery of this animal, here named Zhuchengtyrannus magnus gen. et sp. nov., adds to the known diversity of tyrannosaurids in Asia. Z. magnus can be identified by a horizontal shelf on the lateral surface of the base of the ascending process, and a rounded notch in the anterior margin of the maxillary fenestra. Several additional features contribute to a unique combination of character states that serves to further distinguish Z. magnus from other taxa. Comparisons with other tyrannosaurids suggest that Zhuchengtyrannus was a very large theropod, comparable in size to both Tarbosaurus and Tyrannosaurus.     

宁夏恐龙足迹的发现及其意义

报道了在宁夏固原首次发现的恐龙足迹化石。该恐龙足迹化石分别为鸟脚类恐龙足迹和蜥脚类恐龙足迹,均发现于早白垩世李洼峡组沉积地层中。其中的鸟脚类恐龙足迹命名为六盘山宁夏足印 ( Ningxiapus liupanshanensis ichnogenus et inchnosp． nov． ) 。六盘山宁夏足印长与宽之比为1. 22; 第I 趾纤细,短于第IV 趾; 第II 趾与第III 趾之间夹角为35°,第III 趾与第IV 趾之间夹角为45° 等特征区别于其他鸟脚类恐龙脚印。新发现的蜥脚类恐龙以足迹化石形式保存,其前、后足印的长度大小分别为36 cm 和15 cm,应为中等大小的蜥脚类恐龙所留下。这些恐龙足迹化石的发现,为研究该地区的古生物地理及古生态的恢复以及为将来在该地区发现恐龙骨骼化石提供重要信息。     

山东莒南地质公园发现小型兽脚类恐龙 足迹化石Minisauripus

在山东省莒南地质公园内发现6个小型恐龙足迹化石,被归入足迹属Minisauripus。化石产于下白垩统大盛群田家楼组．时代为早白垩世巴列姆（Barremian）-阿普特期（Apdan）。5个较大,长约6cm,产于下部“主”层面上,其中4个组成2节行迹：1个较小,长约3cm,位于“主”层面30cm之上的上部层面上。山东Minisauripus的特征是：足迹个体小（长3．1～5．6cm,宽2．0～3．7cm）,三趾型,略不对称;足迹纵长,各趾近平行,趾垫较清晰;趾末端较钝,但爪迹较尖。Ⅲ趾比Ⅳ趾略长,而Ⅳ趾比Ⅱ趾略长且窄。此外,步幅较长,足长与步长之比约为10：1。与四川、韩国Minisau却淞不同之处是：足迹个体较大,长约是它们的2倍。继中国四川和韩国之后,山东是Minisau而淞在全球的第三个发现点。     

山东莒南地质公园发现小型兽脚类恐龙足迹化石MinisauripUS

在山东省莒南地质公园内发现6个小型恐龙足迹化石,被归入足迹属Minisauripus。化石产于下白垩统大盛群田家楼组．时代为早白垩世巴列姆（Barremian）-阿普特期（Apdan）。5个较大,长约6cm,产于下部“主”层面上,其中4个组成2节行迹：1个较小,长约3cm,位于“主”层面30cm之上的上部层面上。山东Minisauripus的特征是：足迹个体小（长3．1～5．6cm,宽2．0～3．7cm）,三趾型,略不对称;足迹纵长,各趾近平行,趾垫较清晰;趾末端较钝,但爪迹较尖。Ⅲ趾比Ⅳ趾略长,而Ⅳ趾比Ⅱ趾略长且窄。此外,步幅较长,足长与步长之比约为10：1。与四川、韩国Minisau却淞不同之处是：足迹个体较大,长约是它们的2倍。继中国四川和韩国之后,山东是Minisau而淞在全球的第三个发现点。     

An abelisauroid dinosaur from the Middle Jurassic of Laurasia and its implications on theropod palaeobiogeography and evolution

We review here the phylogenetic relationships of a theropod distal end of tibia (MB. R.2351) from the Middle Jurassic Stonesfield Slate (Taunton Formation, middle Bathonian) of Oxfordshire, England. This specimen was previously described as a small basal tetanuran, but our reinterpretation suggests that it was an early member of the Abelisauroidea. The new assignment is supported by the presence of an apomorphic vertical facet for the reception of the ascending process of the astragalus, sub-rectangular anterior scar of the astragalar ascending process, median vertical ridge in the scar for the reception of the ascending process of the astragalus, and posterolateral process not distinctly offset from the lateral margin of the shaft. In particular, the Stonesfield specimen shares an overall morphology and a unique combination of apomorphies with the Middle Jurassic Australian abelisauroid Ozraptor. Nevertheless, both specimens differ in some punctual features. MB. R.2351 constitutes the oldest evidence of an abelisauroid outside Gondwana and indicates that the group had achieved a Pangean distribution during, at least, the Middle Jurassic. Thus, the initial diversification of abelisauroids would have occurred earlier than previously thought. Accordingly, the Middle and Late Jurassic Pangean distribution of abelisauroids implies that the absence of the group in Cretaceous Asiamerican assemblages would reflect a regional extinction, in which a competitive replacement with coelurosaurs (e.g. tyrannosauroids) is surely one of the hypotheses that should be tested in future studies.     

陕西商洛地区下白垩统大型兽脚类恐龙足迹

记叙了中国陕西省商洛市邵涧村下白垩统东河群2个大型兽脚类恐龙足迹,并将其归于Megalosauripus isp.。 东河群的时代与热河生物群同期,邵涧Megalosauripus isp. 可能可与热河生物群的大型兽脚类恐龙之足部形态做简 单对比。此外,邵涧Megalosauripus isp.造迹者的体长约为7.4m,这意味着早白垩世的陕西中南部亦存在着大型的 兽脚类恐龙。邵涧Megalosauripus isp.的发现,不仅为中国早白垩世恐龙足迹增加了新的成员,而且为将来在该地 区下白垩统中发现大型兽脚类恐龙的骨骼化石提供了确凿的依据。     

陕西中鸡发现白垩纪恐龙足迹群

在鄂尔多斯盆地东北缘神木市中鸡一带下白垩统洛河组上部紫红色薄层砂岩层面中,发现丰富的恐龙与其他四足类的足迹化石。这些足迹可分为3类,分别为三趾型兽脚类足迹(实雷龙足迹类),两趾型兽脚类足迹(恐爪龙类足迹)和小型四足类足迹(哺乳形类/兽孔类足迹)。此种组合在中国尚属首次发现,对古气候、古环境、古地理和地层对比都具有重要的意义。     

汝阳盆地早白垩世恐龙蛋壳的发现及其意义

汝阳盆地是豫西地区的一个中—新生代断陷盆地,自2006年以来发现了一个以巨型蜥脚类恐龙为代表的恐龙动物群。本文描述了近期发现于汝阳盆地下白垩统郝岭组中的若干恐龙蛋蛋壳碎片。基于以下对蛋壳宏观形态和显微特征的分析,这些蛋壳碎片可以归入长形蛋科(Elongatoolithidae)的长形蛋属(Elongatoolithus):蛋壳外表面具分散瘤点状或线性脊状的纹饰;蛋壳自内而外分为锥体层和柱状层,二层之间的界线不清晰;锥体层中锥体排列紧密;柱状层中具波浪状的平行生长纹。这一发现代表了长形蛋属在早白垩世地层中的首次记录,进一步拓展了该蛋属的地史和古地理分布。由以往已知的化石关联推测,这些蛋壳可能与该层位中的窃蛋龙类如刘店洛阳龙(Luoyanggia liudianensis)等具有相关性,表明汝阳盆地在早白垩世晚期具有适宜该类恐龙生存与繁殖的环境。     

陕西甘泉发现中侏罗世恐龙足迹群

恐龙足迹化石是重建鄂尔多斯盆地侏罗纪恐龙动物群的重要途径。在野外地质调查和室内研究的基础上,对陕西甘泉中侏罗世直罗组发现的恐龙足迹群进行了简要记述。初步研究结果表明,甘泉恐龙足迹群具有较强的多样性,足迹类型包括了兽脚类、蜥脚类、可能的鸟脚类及龟鳖类足迹;兽脚类足迹呈现高度多样化,包括大型、中型和小型的三趾型足迹和大型的四趾型足迹;蜥脚类足迹可归入雷龙足迹;可能的鸟脚类足迹保存较差,难以归入到具体属种;可能的龟鳖类足迹为鄂尔多斯盆地侏罗系的首次记录。甘泉恐龙足迹群的发现,扩大了中国恐龙足迹的地理分布,对于重建鄂尔多斯盆地侏罗纪恐龙动物群及古生态、古地理、古环境等具有重要意义。     

A reassessment of large theropod dinosaur tracks from the mid-Cretaceous (late Albian-Cenomanian) Winton Formation of Lark Quarry, central-western Queensland, Australia: A case for mistaken identity

Multivariate analysis is used to differentiate shape variations between ichnites of theropod and ornithopod dinosaurs. Tracks of an alleged theropod cf. Tyrannosauropus from the mid-Cretaceous (late Albian-Cenomanian) Winton Formation of Lark Quarry, central-western Queensland, Australia were examined and foot shape ratios calculated. Multivariate analysis of these shape variables indicates this track-maker was an ornithopod dinosaur. A strong morphological similarity exists between the Lark Quarry ichnites and those of the iguanodontian ichnotaxon Amblydactylus gethingi. Considering the grade of ornithopod this ichnogenus is thought to represent (a non-hadrosaurid styracosternan) and the age and geography of Lark Quarry, we suggest that the track-maker may have been a dinosaur similar to Muttaburrasaurus langdoni.     

Palynoassemblages associated with a theropod dinosaur from the Snow Hill Island Formation (lower Maastrichtian) at the Naze,James Ross Island,Antarctica

The Cape Lamb Member of the Snow Hill Island Formation at The Naze on the northern margin of James Ross Island, east of the Antarctic Peninsula, yielded a theropod dinosaur recovered near the middle of a 90 m thick section that begins at sea level, ends below a basalt sill, and is composed of interbedded green–gray massive and laminated fine-grained sandstones and mudstones. Sixteen palynoassemblages were recovered from this section, which yielded moderately diverse assemblages with a total of 100 relatively well-preserved species. The principal terrestrial groups (32%) are represented by lycophytes (8 species), pteridophytes (15 species), gymnosperms (13 species), angiosperms (21 species) and freshwater chlorococcaleans (3 species). Marine palynomorphs (68%) belong to dinoflagellates (61 species), chlorococcaleans (6 species), and one acritarch. The vertical distribution of selected species allows the distinction of two informal assemblages, the lower Odontochitina porifera assemblage from the base to its disappearance in the lower part of the section, and the remaining section characterized by the Batiacasphaera grandis assemblage. The global stratigraphic ranges of selected palynomorphs suggest an early Maastrichtian age for this section and the entombed dinosaur that is also supported by the presence of the ammonoid Kitchinites darwinii. These assemblages share many species with latest Campanian–early Maastrichtian palynofloras from Vega and Humps Islands, New Zealand, and elsewhere in the Southern Ocean, establishing a good correlation among them. The dominance or frequent presence of dinoflagellates throughout the section supports the general interpretation of a shelf marine depocenter. The consistent presence of terrestrial palynomorphs suggests contributions from littoral/inland environments.     

U-Pb systematics of an Upper Carboniferous black shale from South Yorkshire, UK

Open-system behaviour of uraniferous shales, which has been known for many years, has discouraged attempts to use U-Pb geochronology to date sedimentary systems. Techniques now available can facilitate better understanding of their geochemical evolution and their possible use in geochronometry. For the U-rich Alton (G. listeri) Marine Band, a combined fission track mapping, electron optical and sequential chemical extraction study confirms that uranium is incorporated into francolite, an early diagenetic precipitate. U-Pb analyses of uranium-rich (>1000 ppm) francolite nodules are discordant and imply ages ∼50-150 Ma younger than the date of sedimentation. Pb isotopic analysis suggests that uranium daughters continually leaked from the francolite, ²³⁸U daughters being released more efficiently than those of ²³⁵U. Extrapolation of the U-Pb data to concordia produces an age consistent with the time of sedimentation. These features are also displayed by other uranium-rich shales such as the Swedish Kolm Measures, despite uranium being incorporated into different phases. Preferential loss of ²³⁸U daughters from fine-grained particles due to alpha recoil could explain the unusual U-Pb isotopic composition, in both examples. Further work would be justified to investigate the application of U-Pb isotopic analysis of such material to date sedimentary sequences.