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1.
Here we report a large dinosaur tracksite from an extensive fluvial sandstone surface in the Lower Cretaceous Jiaguan Formation of Sichuan Province, China. The site contains over 250 individual tracks comprising at least 18 recognizable trackways, including the longest theropod trackway (cf. Eubrontes) known from China. This exceptional theropod trackway consists of 81 successive footprints covering a distance of 69 m. The tracks are well-preserved and are expressed both as true tracks on the main “upper” surface and as transmitted undertracks on a locally exposed “lower” bed. Also recorded are six other theropod trackways, including small Grallator-like ichnites, eight sauropod trackways (cf. Brontopodus), and three small ornithopod (cf. Ornithopodichnus) trackways with a parallel orientation, which may indicate gregarious behavior. Several trackways of a larger theropod trackmaker show pes imprints with elongated traces of the metatarsals, suggesting extramorphological (substrate-controlled) variation and/or plantigrade posture, which is here interpreted as indicating a change in gait assumed in response to deep and soft sediment. The assemblage indicates a diverse dinosaur fauna in the Lower Cretaceous Sichuan Basin with variously sized theropods, sauropods, and ornithopods. The late occurrence of footprints of the Grallator-Eubrontes plexus in Lower Cretaceous strata is further evidence of the extended stratigraphic range of this morphotype and the distinct palaeobiogeographic distribution of these trackmakers in East Asia. 相似文献
2.
The well-preserved trackway of a lacertiform, lizard-like trackmaker from the Haman Formation (Cretaceous) of Korea is described as Neosauroides koreaensis ichnogen. et ichnosp. nov. This is the only example of a Cretaceous lacertiform or lizard-like trackway currently known in the global track record. Although lacertiform trackways, mostly assigned to the ichnogenus Rhynchosauroides, are common in the global Triassic, they are almost entirely absent in the Jurassic and Cretaceous. Moreover, ichnological classification criteria allow that Neosauroides is morphologically distinct from Rhynchosauroides at the genus level, and more like the tracks of the extant lizard Sceloporus. The reasons for the conspicuous lack of post-Triassic occurrences are not certain, but not due to a post-Triassic lack of potential lizard trackmakers. Thus, the preservation biases are likely due to paleobiological factors such as trackmaker ecology and paleoenvironmental preference. 相似文献
3.
基于恐龙足迹重建攀西地区白垩纪恐龙动物群 总被引：2，自引：2，他引：0
攀西地区没有白垩纪恐龙骨骼化石记录,对该区白垩纪恐龙动物群组合的认识尚属空白。1991年,攀西地区首次发现了恐龙足迹,此后陆续发现了8个足迹点。这些足迹点共发现9种不同的非鸟恐龙足迹(6种非鸟兽脚类、1种蜥脚类和2种鸟脚类足迹),以及翼龙和龟类足迹。共11种足迹形态类型由185道行迹(与孤立足迹)组成,可能代表着同等数量的造迹者。其中飞天山组的组合多样性最强,小坝组和雷打树组较弱。这个相对全面的足迹数据库,为该地区白垩纪四足类的古生态学普查提供了动物群的组成信息,这在该缺乏骨骼化石的地区显得尤为重要。 相似文献
4.
A previously unknown and morphologically distinct pentadactyl mammal track was recovered from the Upper Cretaceous (Maastrichtian) Laramie Formation at the Fossil Trace site, a National Natural Landmark which is the type locality for Schadipes crypticus, the only named mammal track known from North America. The track is different, and larger than S. crypticus, and thus is evidence of a diversity of mammal trackmakers at this site. Although Cretaceous mammal tracks are very rare, preliminary indications are that those currently known are all morphologically distinct and therefore indicative of a global diversity of different trackmakers, as the body fossil record suggests. Lack of well-preserved mammal trackways with morphologically distinct manus and pes footprints hampers efforts to name diagnostic ichnotaxa. 相似文献
5.
A sample of fallen blocks of fluvial sandstone from the Lower Cretaceous Jiaguan Formation of Sichuan Province yielded an assemblage of dinosaur and pterosaur tracks preserved as natural impressions and casts. Collectively the assemblage reveals 132 tracks representing at least 30 trackways of tridactyl and didactyl theropods, sauropods, ornithopods and pterosaurs. Ichnotaxonomically, the trackways of small tridactyl theropods (pes lengths 7–18 cm) are indeterminable, whereas the trackway of a small didactyl dromaeosaur (pes length up to 7.5 cm) is tentatively assigned to cf. Velociraptorichnus. The sauropod trackways are assigned to cf. Brontopodus based on the medium to nearly wide-gauge pattern. Other characteristics are the U-shaped manus and strong heteropody. One sauropod trackway shows a peculiar pattern with a lack of left manus imprints, and an unusual position and rotation of right manus imprints. Different scenarios and explanations for this phenomenon are discussed. Ornithopod trackways are the most abundant in the sample and characterized by pes imprints of a small biped that are assigned here to the new ichnospecies Caririchnium liucixini. It is characterized by an unusual broad shape and weak mesaxony. Bivariate analysis of different Caririchnium ichnospecies reveals increasing mesaxony toward the larger forms, a trend that is the reverse of typical theropod ichnotaxa, where large imprints have weak mesaxony. Three isolated, small pterosaur tracks (two manus, one pes) are visible on a single surface. They show strong similarities to the widespread ichnogenus Pteraichnus. This is the ninth report of tetrapod tracks from the Jiaguan Formation in recent years and represents one of the most diverse assemblages recorded to date. It is also rare evidence of typical didactyl dromaeosaur tracks and the co-occurrence of sauropod and ornithopod tracks in a fluvial depositional environment representing arid climate conditions. 相似文献
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7.
藏东昌都地区阿涅塘化石点中侏罗世达布卡组滨湖相紫红色中-细砂岩中,发现以凸形迹完好地保存的4层恐龙足迹,包括Grallator类、大型兽脚类、小型兽脚类和小型蜥脚类等足迹类型,并构成两列完美的行迹. 组成行迹T1的4个Grallator类足迹被命名为Grallator anietangensis isp. nov.,对其进行了详细的形态学分析,并讨论了造迹恐龙的大小和运动状态,这是Grallator类足迹在西藏地区的首次发现. 组成行迹T2的9个大型兽脚类足迹被归为Theropoda igen. et isp. indet.,对该类足迹进行了形态描述和功能分析;这类足迹在中国是首次记录,其连续且清晰的尾迹表明造迹者并非处于正常运动状态,而是应对某种特殊境况的特别行为方式,即其正以昂起的前躯一边观察,一边以极低的速度前进,因前躯昂起,尾部相应下垂,从而留下尾迹. 两列行迹均显示出造迹者正沿古昌都湖岸前进. 中国迄今所发现的恐龙骨骼和Grallator类足迹化石主要表现为以西南地区为中心,再向四周不断发散的扩散模式,但Grallator类足迹化石综合提供的信息显示恐龙动物的扩散速度比骨骼化石反映的速度更快. 相似文献
8.
In Sung Paik Min Huh Kye Hun Park Koo Geun Hwang Kyung Sik Kim Hyun Joo Kim 《Journal of Asian Earth Sciences》2006,28(4-6):457-468
Eighty two dinosaur trackways were newly discovered in Upper Cretaceous lacustrine deposits on islands in the vicinity of Yeosu, Korea. Most dinosaur tracks occur in marginal lake deposits with polygonal desiccation cracks. The dinosaur tracks at the Yeosu site include 65 ornithopod trackways, 16 theropod trackways and one sauropod trackway. The prevalence of ornithopod tracks and the limited occurrence of sauropod tracks at the Yeosu site evidently reflect decreased sauropod diversity in the Upper Cretaceous. All ornithopod trackways represent bipeds, and most of the ornithopod tracks are similar to Caririchnium from other sites of the Korean peninsula. All fossil wood specimens collected in the study area represent conifers (three species of cupressaceous and two species of taxodiaceous conifers, and a new species) except for one, which is a discotyledon. It is thus inferred that the southwestern part of the Korean Peninsula was primarily covered with mesic forests with taxodiaceous trees during the Late Cretaceous. The K–Ar age of the Yeosu tracksite is determined as 81–65 Ma (Camapnian to Maastrichtian). It indicates that the Yeosu track site contains the last records of dinosaurs living in Asia. Consequently, semi-arid palaeoclimatic conditions, together with a large lake as a persistent water source and rich vegetation of gymnosperm trees as food, resulted in the preservation of abundant dinosaur tracks in the Upper Cretaceous on the Korean Peninsula. 相似文献
9.
Lida Xing Martin G. Lockley Dongjie Tang Hendrik Klein Guangzhao Peng Yong Ye Baoqiao Hao 《地学前缘(英文版)》2019,10(1):229-240
The newly discovered large(350 m^2) Yantan dinosaur tracksite, in the Lower Jurassic Ziliujing Formation of Guizhou Province, China, reveals at least 250 footprints of which ~97 can be resolved into trackways of sauropodomorphs. All the trackways are sub parallel likely indicating gregarious behavior. One theropod track(cf. Grallator) was recorded. The sauropodomorph tracks predominantly represent quadrupedal progression(Morphotype A), and footprint morphology is similar to the ichnospecies Liujianpusshunan, characterized by outward pes rotation. Three trackways indicate bipedal progression, and two of these(Morphotype B) indicate inward pes rotation, accompanied by elongate pes digit scratch marks. For the latter phenomenon three possible scenarios are discussed:(1) significant rotation changes accompanying changes in gait,(2) swimming behavior,(3) formation of undertracks.Sedimentological evidence indicates the tracks were made on a linguloid rippled, muddy, immature sandstone substrate characterized by significant differences in substrate consistency across the trackbearing surface. Microbially induced sedimentary structures(MISS) characterized by distinctive wrinkle marks indicate a stressed, probably semi-arid, paleoenvironment that was not conducive to habitation by invertebrate organisms. This is consistent with other evidence that Lower Jurassic sauropodomorph tracks are often associated with semi-arid paleoenvironments. 相似文献
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A new Lower Cretaceous (lower Aptian) dinosaur tracksite, from the eastern side of Monte Cagno (Abruzzi, Italy), is described. Different styles of track formation are represented on the site surface. Most of the footprints are preserved as deep tracks, produced by trackmakers sinking into soft mud. Some tracks, better preserved than the others, are characterized by metatarsal impressions and were interpreted as the resting traces of a crouching theropod (based on their orientation and three-dimensional morphology). The 135 cm length of the track with metatarsal impressions indicates huge pedal proportions and represents the largest theropod trackmaker ever documented from the Mesozoic peri-Adriatic platforms of Italy. 相似文献
12.
Yuong-Nam Lee 《Cretaceous Research》1997,18(6):849-864
The ichnofauna of the Woodbine Formation (Cenomanian), Denton County, Texas includes bird and dinosaur tracks. A new bird trackway,Magnoavipes loweiichnogen. et ichnosp. nov., appears to represent the largest bird tracks known from the Mesozoic. A theropod trackway,Fuscinapedis woodbinensisichnogen. et ichnosp. nov., is characterized by long digits of uniform width and pointed small claws. Six hadrosaurid trackways,Caririchnium protohadrosaurichnosichnosp. nov., are the oldest hadrosaurid tracks associated with skeletal elements. They include one isolated small footprint, a medium sized quadrupedal, and five large bipedal hadrosaurid trackways. 相似文献
13.
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。 相似文献
14.
简要报道了新近首次在冀西北张家口尚义地区发现的恐龙足迹。野外地质调查发现,恐龙足迹赋存于尚义晚中生代盆地侏罗系—白垩系后城组顶部。恐龙行迹呈近东西向展布,由数十个足迹构成。初步研究表明,造迹者分别属于兽脚类和蜥脚类恐龙,由西向东行进。足迹中包括兽脚类足迹70余个,组成数个行迹;蜥脚类足迹15个,构成1列行迹。蜥脚类足迹特征显示其可能属于游泳状的行迹。华北北部土城子组/后城组发育于燕辽生物群—热河生物群更替演化时期（晚侏罗世—早白垩世早期）,以往在该时期沉积物中罕见脊椎动物骨骼化石。近年来华北北部土城子组/后城组中频繁发现的恐龙足迹表明,燕辽生物群—热河生物群更替演化时期发育着以恐龙为代表的脊椎动物群。该发现将有助于进一步了解土城子组/后城组沉积时期恐龙属种的多样性及其生物古地理环境。晚侏罗世—早白垩世早期沉积古地理和古生态环境及其与恐龙动物群发育的研究有助于揭示陆地生物群更替演化和环境的关系。 相似文献
15.
山东诸城黄龙沟恐龙足迹产于下白垩统中部莱阳群杨家庄组,其中以兽脚类为主,同时有蜥脚类和疑似鸟脚类足迹;兽脚类足迹又可进一步区分为大型兽脚类、似跷脚龙类(Paragrallator）和东方强壮百合龙类(Corpulentapus lilasia）。足迹共组成至少63条行迹,作者系统实测了其中50条,并据足迹大小指数—复步长和GAE(跷脚龙—安琪龙—实雷龙）图解给出了识别3类兽脚类足迹的经验性数值。足迹点沉积特征显示,浅湖相粉砂质泥岩和粉砂岩逐渐过渡为滨湖相砂岩。足迹层及其邻近层位波痕、泥裂发育,根据波脊线恢复的古岸线方向为东西向,波浪运动方向呈现出北至北西周期性变化,表明可能存在季节性风向变化。泥裂以及恐龙分布特征显示足迹点以S/WS为湖心方向,以N/EN为湖岸方向。似跷脚龙类和东方强壮百合龙类足迹分布区域的差异性表明东方强壮百合龙类生活区域更靠近湖岸。恐龙足迹中存在的明显叠盖现象表明足迹不是同时,而是多次活动遗迹。小型兽脚类行迹中较多近于平行的行迹体现了集群性生活习性。行进行为研究又显示兽脚类的绝大多数为快速奔跑状态,但蜥脚类等为慢行状态。兽脚类与蜥脚类、疑似鸟脚类足迹数量之比远大于正常捕食者和被捕食者之比也表明,早白垩世中期的胶莱盆地生存着以兽脚类为主、蜥脚类和鸟脚类为辅的恐龙动物群。早白垩世晚期,胶莱盆地以及沂沭断裂带内蜥脚类、鸟脚类恐龙以及鸟类逐渐繁盛,这与华北北部恐龙足迹所恢复的造迹恐龙动物群特征较为一致。中国北方、韩国、日本白垩纪恐龙足迹以及骨骼化石发育情况暗示,晚中生代中国北方以及东亚地区发育一个以恐龙等脊椎动物为主的大型陆地动物群。 相似文献
16.
贵州省拥有丰富的中生代脊椎动物化石记录,多为三叠纪海生爬行类化石,侏罗纪和白垩纪的脊椎动物化石较少。目前,贵州省已发现中生代爬行类足迹点9处,分别为贞丰牛场、贞丰龙场、安顺幺铺、赫章辅处、毕节响水(2处)、仁怀茅台、赤水宝源和习水同民足迹点。文中除描述了贞丰龙场新增的一批足迹化石外,整理并总结了所有足迹点的发现史、研究现状、足迹类型与特征以及所反映的古生态信息。已发现的遗迹记录由69条行迹和420个孤立足迹组成,足迹总数达991个。所有的遗迹化石指示了至少477个造迹者,包括海生爬行类、手兽足迹类、非鸟兽脚类、鸟类、蜥脚类和鸟臀类等,其中三叠纪以海生爬行类主导,侏罗纪和白垩纪以蜥臀类主导。这个数据集为贵州中生代古生物类群的多样性提供了重要的信息,是晚中生代稀缺骨骼化石记录的良好补充,为研究贵州省中生代脊椎动物群的古生态与古环境提供了更多的证据。 相似文献
17.
Trackways can provide unique insight to animals locomotion through quantitative analysis of variation in track morphology. Long trackways additionally permit the study of trackmaker foot anatomy, providing more insight on limb kinematics. In this paper we have restudied the extensive tracksite at Barranco de La Canal-1 (Lower Cretaceous, La Rioja, NW Spain) focussing on a 25-m-long dinosaur (ornithopod) trackway that was noted by an earlier study (Casanovas et al., 1995; Pérez-Lorente, 2003) to display an irregular pace pattern. This asymmetric gait has been quantified and photogrammetric models undertaken for each track, thus revealing distinct differences between the right and the left tracks, particularly in the relative position of the lateral digits II–IV with respect to the central digit III. Given that the substrate at this site is homogenous, the consistent repetition of the collected morphological data suggests that differences recorded between the right and the left tracks can be linked to the foot anatomy, but more interestingly, to an injury or pathology on left digit II. We suggest that the abnormal condition registered in digit II impression of the left pes can be linked to the statistically significant limping behaviour of the trackmaker. Furthermore, the abnormal condition registered did not affect the dinosaur's speed. 相似文献
18.
Christian Gaillard 《Swiss Journal of Geoscience》2011,104(1):57-72
A well-preserved large limulid trackway related to Kouphichnium lithographicum is described from the Upper Kimmeridgian Lithographic Limestones of Cerin (Ain, France). It is three meters long and exhibits ten successive sets of imprints characterized by a pair of well-preserved tetradactyl external imprints of legs VI (named pushers) and a variable number (mostly three pairs) of straight thin intermediate imprints (legs III–V). The trackway is unusually wide and was probably made by a very large adult approximately 38 cm wide and 80 cm long when related to the proportions of the modern Limulus polyphemus. The straightness of the trackway, the great repeat distance (stride), the length of series of leg imprints, their slight angle to the mid-line, the well-marked pusher (= leg VI) imprints and the absence of groove made by the telson all indicate fast progression of a vigorous animal on the sea-floor. This walking trackway can be easily differentiated from other limulid crawling, ploughing, and dying trackways usually found in lithographic limestones or other deposits of the geological record. Main characteristics of these different limulid trackways are evidenced. The occurrence of a living adult in the Cerin restricted lagoon is probably related to a brief period of connection with the open sea. This occurrence indicates either a passive introduction of the animal into the lagoon or a spawning behaviour. 相似文献
19.
An unusual theropod track assemblage from the Cretaceous of the Zhucheng area, Shandong Province, China 总被引：3，自引：0，他引：3
More than 125 footprints of theropods from the Cretaceous Longwangzhuang Formation have been mapped in a preliminary study at a site in the Zhucheng region of China. The tracks represent at least three morphotypes. The largest morphotype is a large theropod (footprint length ∼30 cm) represented by a single trackway and an isolated natural cast. At least 10 trackways assigned to the new ichnospecies Corpulentapus lilasia represent a medium-sized biped (footprint length ∼13 cm) with very short, wide, robust, ‘tulip-shaped’ tracks and long steps (∼5 × footprint length), and a short central digit (III) indicating weak mesaxony. Corpulentapus trackways are narrow and theropod-like even though track morphology is convergent with the footprints of some ornithopods. The third morphotype, made by a medium-sized grallatorid track maker (ichnogenus Paragrallator), is about the same size (∼13 cm) as the robust morphotype, but far more elongate and gracile, with an elongate central digit (III) indicating strong mesaxony. This ichnotaxon requires detailed comparison with Grallator sensu stricto. The contrast in morphology between the two common morphotypes is striking and demonstrates that two distinct medium-sized taxa of presumed theropod affinity frequented the same habitat in significant numbers. 相似文献
20.
Adolfo Panarello Maria Rita Palombo Italo Biddittu Mauro Antonio Di Vito Gennaro Farinaro Paolo Mietto 《第四纪科学杂志》2020,35(3):444-456
The Foresta ichnosite is well known for preserving some of the oldest human fossil footprints recorded in Europe so far. This research aims to: i) describe new footprints that are larger than those already reported, some of which form a new trackway that moves in the opposite direction to all the others; ii) announce the discovery of some stone tools also in the surroundings of the Foresta ichnosite. The new results increase the total number of human fossil footprints to at least 81, specify the direction and the number of footprints of Trackway C, and identify three new directions of walking at the site. More compelling and complete estimates of the dimensional range of all ichnological evidence enables us, furthermore, to estimate the number of trackmakers walking on the trampled surface as a minimum of five, one of them likely being an adult male. The general shape of all the recorded footprints suggests that the Foresta trackmakers share some similarities with those at Sima de los Huesos, and belong to the same taxonomical group as the Ceprano skull. All the new evidence enables us to better understand the presence of hominin populations in the Roccamonfina volcano area during the Middle Pleistocene. © 2020 John Wiley & Sons, Ltd. 相似文献