A large-clawed theropod (Dinosauria: Tetanurae) from the Lower Cretaceous of Australia and the Gondwanan origin of megaraptorid theropods

Megaraptoridae comprises a clade of enigmatic Gondwanan theropods with characteristic hypertrophied claws on the first and second manual digits. The majority of megaraptorids are known from South America, although a single genus (Australovenator) plus additional indeterminate material is also known from Australia. This clade has a controversial placement among theropods, and recently has been interpreted alternatively as a carcharodontosaurian or a tyrannosauroid lineage. We describe new fragmentary but associated postcranial remains from the opal fields of Lightning Ridge (middle-Albian, Griman Creek Formation) in north-central New South Wales. The new unnamed taxon exhibits a number of unusual features that suggest the presence of a hitherto unrecognised Australian megaraptorid. From an Australian perspective, the Lightning Ridge taxon predates Australovenator by ca. 10 Ma and is minimally coeval with megaraptoran material reported from the Eumeralla Formation of Victoria (but potentially 6.1–9.5 Ma younger). It is also notable as the largest predatory dinosaur yet identified from Australia and is only the second theropod known from more than a single element. A Bayesian phylogenetic approach integrating morphological, stratigraphic and palaeogeographic information tested both the carcharodontosaurian and tyrannosauroid placements for Megaraptora. Regardless of the preferred placement among Tetanurae, rigorous palaeobiogeographic analyses support an Asian origin of Megaraptora in the latest Jurassic (about 150–135 Ma), an Early Cretaceous (about 130–121 Ma) divergence of the Gondwanan lineage leading to Megaraptoridae, and an Australian root for megaraptorid radiation. These results indicate that Australia's Cretaceous dinosaur fauna did not comprise simply of immigrant taxa but was a source for complex two-way interchange between Australia–Antarctica–South America leading to the evolution of at least one group of apex predatory dinosaurs in Gondwana.     

Gondwanan dinosaur evolution and biogeographic analysis

Gondwanan dinosaurs, though less well-known than their Laurasian counterparts,are being discovered and described at an ever accelerating pace. Dinosaurs are known from every major Gondwanan landmass, including South America, Africa, Antarctica, Australia, India, Madagascar and New Zealand. Much of the Gondwanan dinosaur literature includes speculation on vicariant and dispersal events relating to the fragmentation of Gondwana during the Jurassic and Cretaceous. These prolific biogeographic hypotheses are often inconclusive, speculative in nature, and untestable with the data at hand. To formulate well-supported biogeographic hypotheses, resolved dinosaur phylogenies and sound hypotheses of Earth history are necessary. Other factors, such as taphonomy, depositional setting, and missing taxonomic, temporal and geographic data, also contribute to understanding dinosaur faunal compositions. Additional phylogenetic information, a continuation of the current exploration and discovery, and knowledge of recent advances in tectonic plate reconstructions are paramount to developing a well-supported view of Gondwanan dinosaur biogeography.     

An abelisaurid from the latest Cretaceous (late Maastrichtian) of Morocco,North Africa

During the latest Cretaceous, distinct dinosaur faunas were found in Laurasia and Gondwana. Tyrannosaurids, hadrosaurids, and ceratopsians dominated in North America and Asia, while abelisaurids and titanosaurians dominated in South America, India, and Madagascar. Little is known about dinosaur faunas from the latest Cretaceous of Africa, however. Here, a new abelisaurid theropod, Chenanisaurus barbaricus, is described from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa on the basis of a partial dentary and isolated teeth. Chenanisaurus is both one of the largest abelisaurids, and one of the youngest known African dinosaurs. Along with previously reported titanosaurian remains, Chenanisaurus documents the persistence of a classic Gondwanan abelisaurid-titanosaurian fauna in mainland Africa until just prior to the end-Cretaceous mass extinction. The animal is unusual both in terms of its large size and the unusually short and robust jaw. Although it resembles South American carnotaurines in having a deep, bowed mandible, phylogenetic analysis suggests that Chenanisaurus may represent a lineage of abelisaurids that is distinct from those previously described from the latest Cretaceous of South America, Indo-Madagascar, and Europe, consistent with the hypothesis that the fragmentation of Gondwana led to the evolution of endemic dinosaur faunas during the Late Cretaceous.     

Tetrapods from the Upper Cretaceous (Turonian–Maastrichtian) Bauru Group of Brazil: a reappraisal

An updated, annotated list of all tetrapods from the Adamantina, Uberaba and Marília formations (Bauru Group), which constitute some of the best studied Upper Cretaceous units in Brazil, is presented. Tetrapod diversity in the Bauru Group is remarkable, including an admixture of typically austral Gondwanan taxa (e.g., abelisaurids, notosuchians) and boreal Gondwanan forms (e.g., carcharodontosaurids). Of note is the absence of Laurasian taxa in the upper portion of the Bauru Group. With the exception of some turtles, an anuran, mesoeucrocodylians and one titanosaur, most taxa from the Bauru Group are based on fragmentary and isolated bones, and as such many specimens can be identified only to a higher taxonomic level. Fishes, turtles, anurans, mesoeucrocodylians, dinosaurs, birds and mammals from the Adamantina and Marília formations resemble the latest Late Cretaceous vertebrate faunas from southern South America, except for the absence of ornithischian dinosaurs.     

Archosaurian reptiles with Gondwanan affinities in the Upper Cretaceous of Europe

The Late Cretaceous (mainly Campanian and Maastrichtian) non-marine vertebrate faunas of Europe contain archosaurian reptiles which belong to groups otherwise known mainly or only from the southern ('Gondwanan') continents. They include titanosaurid sauropods, abelisaurid theropods, and trematochampsid crocodilians. The occurrence of these forms together with others of 'Asiamerican' affinities gives the Late Cretaceous vertebrate faunas of Europe a peculiar composition, which makes them clearly different from the well-known faunas from western North America and Central Asia. The Gondwanan dinosaurs and crocodilians from Europe provide evidence of faunal interchange across the Tethys Sea during the Cretaceous, possibly via the Alboran plate, or the Apulian plate, which may have functioned as 'stepping-stones', especially during periods of low sea level.     

A new alvarezsaurid dinosaur from the Late Cretaceous Qiupa Formation of Luanchuan,Henan Province,central China

An alvarezsaurid dinosaur skeleton was discovered from the Late Cretaceous Qiupa Formation of Luanchuan, Henan Province of central China. It represents a new alvarezsaurid dinosaur Qiupanykus zhangi gen. et sp. nov. A phylogenetic analysis recovers Qiupanykus nested within the unresolved clade, which includes Asian and north American taxa. The skeleton of the new specimen is preserved in association with eggshells. The eggshell morphologies show that these eggs belong to oviraptorid eggs, skeletal remains of which were discovered from the same area. The alvarezsaurid skeleton associated with eggshell fragments may indicate that these eggs were broken by the strong thumb-claws of the former and that alvarezsaurid dinosaurs may be egg-eaters.     

“Megalosaurus cf. superbus” from southeastern Romania: The oldest known Cretaceous carcharodontosaurid (Dinosauria: Theropoda) and its implications for earliest Cretaceous Europe-Gondwana connections

Some of the best records of continental vertebrates from the Cretaceous of Europe come from Romania, particularly two well-known occurrences of dwarfed and morphologically aberrant dinosaurs and other taxa that lived on islands (the Cornet and Haţeg Island faunas). Substantially less is known about those vertebrates living in the more stable, cratonic regions of Romania (and Eastern Europe as a whole), particularly during the earliest Cretaceous. We describe one of the few early Early Cretaceous fossils that have ever been found from these regions, the tooth of a large theropod dinosaur from Southern Dobrogea, which was discovered over a century ago but whose age and identification have been controversial. We identify the specimen as coming from the Valanginian stage of the Early Cretaceous, an incredibly poorly sampled interval in global dinosaur evolution, and as belonging to Carcharodontosauridae, a clade of derived, large-bodied apex predators whose earliest Cretaceous history is poorly known. Quantitative analyses demonstrate that the Romanian tooth shows affinities with a derived carcharodontosaurid subgroup, the Carcharodontosaurinae, which until now has been known solely from Gondwana. Our results suggest that this subgroup of colossal predators did not evolve vicariantly as Laurasia split from Gondwana, but originated earlier, perhaps in Europe. The carcharodontosaurine diversification may have been tied to a north-to-south trans-Tethyan dispersal that took place sometime between the Valanginian and the Aptian, illustrating the importance of palaeogeographic ties between these two realms during the largely mysterious early–mid Early Cretaceous.     

白垩纪四足动物足印的生物地层学、生物年代学与遗迹相

从全球范围来看,白垩纪四足动物的足印多数是非鸟恐龙与鸟类留下的痕迹;少量足印来自翼龙、鳄鱼、龟、哺乳动物和其他四足动物。白垩纪的足迹化石以东亚(尤其是中国和朝鲜)和北美西部的最为人所知。南美(主要是阿根廷和巴西)也有一定数量广泛分布的足迹化石,欧洲、非洲与澳大利亚的白垩纪足迹组合则鲜为人知。以白垩纪四足动物的足印记录为基础,我们对两个全球足印生物年代重新进行了检查。早白垩世生物年代以蜥脚类与鸟脚类的足迹为特征。晚白垩世生物年代中的蜥脚类足迹较少,但是鸭嘴龙、暴龙和角龙的足迹增多了。另外,白垩纪足印化石的记录中记载了许多重要的生物地层学信息,如北美白垩纪中期蜥脚类恐龙的消失,以及白垩纪末恐龙的绝灭。越来越多来自东亚的白垩纪足印记录使我们对更精细的地方性白垩纪足印生物年代学有了初步印象。因此,以地方性四足恐龙(包括鸟类)遗迹属的地层分布为基础,可以识别出三个或四个足印生物年代。种类丰富并具有地方性特色的东亚的白垩纪鸟类动物的遗迹群,可能指示白垩纪时东亚存在着一个独特而繁盛的鸟类动物群。以足印化石为基础的这一假说有待进一步的验证。     

Radiometric dating demonstrates that Permian spore‐pollen zones of Australia and South Africa are diachronous

The well-refined Permian palynozonation of Western and eastern Australia is the current standard biostratigraphic scheme for the Southern Hemisphere, but intra-Gondwanan floristic provincialism means that several stratigraphically useful palynomorph taxa are rare or absent elsewhere in Gondwana. Radio-isotopic ages for both Australia and the main Karoo Basin of South Africa demonstrate that key marker taxa appear diachronously in the two countries, or they are absent in one of the countries. The establishment of new plant taxa in the Gondwanan Permian realm was strongly tied to palaeolatitude, with floral distributions primarily affected by temperature, precipitation, and seasonality. This spatio-temporal variation of floras hinders global biostratigraphic correlations. Both South Africa and Australia have excellent long-ranging Permo-Triassic terrestrial sedimentary successions, and although vertebrate biostratigraphy has been the focus of much research endeavour in the South African Karoo, palynological studies have lagged. Accordingly, a new South African palynozonation should be established that is based on the first appearances of key index taxa in the main Karoo Basin, rather than elsewhere in Gondwana. In the interim, the diachronous ranges of palynomorphs must be considered when correlating South African rocks to other global sections by means of the Australian spore‐pollen zonation.     

Diversity and faunal changes in the latest Cretaceous dinosaur communities of southwestern Europe

Characterization of macroecological patterns for latest Cretaceous dinosaur communities is essential to understand how those faunas were changing during the run-up to the Cretaceous-Paleogene extinction event, and thus the cause of the extinction. Outside of the well-studied latest Cretaceous dinosaurs of North America, southwestern Europe (France, Spain and Portugal) preserves one of the richest end-Cretaceous dinosaur fossil records, as it has produced hundreds of dinosaur fossil localities. We compiled a comprehensive database of all dinosaur fossil occurrences from the uppermost Cretaceous of the Ibero-Armorican region and analyze it statistically, providing the first numerical study of the ecological and taxonomic diversities of these communities. Our study corroborates previous work that has identified a major faunal change in the latest Cretaceous terrestrial vertebrate assemblages, and places this event around the C31r-C31n reversal, in the early late Maastrichtian (c. 69 Ma). Significant differences in ecological diversity metrics (dominance, Shannon and Simpson) characterize the pre- and post-turnover assemblages. The turnover event, therefore, did not only lead to a taxonomic replacement but also important reorganizations in the structure of dinosaur communities. Herbivorous dinosaurs suffered the most dramatic alterations across the turnover, in terms of relative dominances, by shifting their contributions within the communities (hadrosauroids replacing titanosaurids as the dominant taxon in the medium-to large-bodied herbivore niche) or even disappearing (rhabdodontids and nodosaurids). The carnivores apparently maintained similar relative abundances before and after the turnover, and the relative proportions between carnivorous and herbivorous taxa remained static through time. Further improvement of the present database might allow for the identification of new ecological patterns, and higher-resolution comparison with the North American records.     

Evolution of the carnivorous dinosaurs during the Cretaceous: The evidence from Patagonia

Patagonia has yielded the most comprehensive fossil record of Cretaceous theropods from Gondwana, consisting of 31 nominal species belonging to singleton taxa and six families: Abelisauridae, Noasauridae, Carcharodontosauridae, Megaraptoridae nov. fam., Alvarezsauridae, and Unenlagiidae. They provide anatomical information that allows improved interpretation of theropods discovered in other regions of Gondwana. Abelisauroids are the best represented theropods in Patagonia. They underwent an evolutionary radiation documented from the Early Cretaceous through to the latest Cretaceous, and are represented by the clades Abelisauridae and Noasauridae. Patagonian carcharodontosaurids are known from three taxa (Tyrannotitan, Giganotosaurus and Mapusaurus), as well as from isolated teeth, collected from Aptian to Cenomanian beds. These allosauroids constituted the top predators during the mid-Cretaceous, during which gigantic titanosaur sauropods were the largest herbivores. Megaraptorans have become better documented in recent years with the discovery of more complete remains. Megaraptor, Aerosteon and Orkoraptor have been described from Cretaceous beds from Argentina, and these taxa exhibit close relationships with the Aptian genera Australovenator, from Australia, and Fukuiraptor, from Japan. The Gondwanan megaraptorans are gathered into the new family Megaraptoridae, and the Asiatic Fukuiraptor is recovered as the immediate sister taxon of this clade. Although megaraptorans have been recently interpreted as members of Allosauroidea, we present evidence that they are deeply nested within Coelurosauria. Moreover, anatomical information supports Megaraptora as more closely related to the Asiamerican Tyrannosauridae than thought. Megaraptorans improve our knowledge about the scarcely documented basal radiation of Gondwanan coelurosaurs and tyrannosauroids as a whole. Information at hand indicates that South America was a cradle for the evolutionary radiation for different coelurosaurian lineages, including some basal forms (e.g., Bicentenaria, Aniksosaurus), megaraptorans, alvarezsaurids less derived than those of Laurasia, and unenlagiids, revealing that Gondwanan coelurosaurs played sharply differing ecological roles, and that they were taxonomically as diverse as in the northern continents. The unenlagiids represent an endemic South American clade that has been recently found to be more closely related to birds than to dromaeosaurid theropods. Analysis of the theropod fossil record from Gondwana shows the highest peak of origination index occurred during the Aptian–Albian and a less intense one in the Campanian time spans. Additionally, peaks of extinction index are recognized for the Cenomanian and Turonian–Coniacian time spans. In comparison, the Laurasian pattern differs from that of Gondwana in the presence of an older extinction event during the Aptian–Albian time-span and a high origination rate during the Cenomanian time-bin. Both Laurasian and Gondwanan theropod records show a peak of origination rates during the Campanian.     

Additions to the sauropod dinosaur fauna of the Cenomanian (early Late Cretaceous) Kem Kem beds of Morocco: Palaeobiogeographical implications of the mid-Cretaceous African sauropod fossil record

Determining the relationships of mid-Late Cretaceous African taxa is central to understanding the timing and resultant palaeobiogeographical patterns of Gondwanan fragmentation. The early Late Cretaceous (Cenomanian) Kem Kem beds of southeastern Morocco preserve a diverse vertebrate fauna, including sauropod dinosaurs. Sauropod material includes the holotype of the rebbachisaurid diplodocoid Rebbachisaurus garasbae and fragmentary remains representing indeterminate titanosauriforms and rebbachisaurids. Here, we describe two new specimens from the Kem Kem beds. A dorsal neural arch with complex internal pneumaticity is tentatively attributed to a somphospondylan titanosauriform. A caudal vertebra possessing several rebbachisaurid synapomorphies is excavated by a large and pervasive lateral pneumatic foramen, a feature undocumented in other rebbachisaurids. However, caudal vertebrae are currently unknown for the sympatric R. garasbae, so this element could be referable to that taxon or a second, previously unknown, rebbachisaurid species. Interestingly, this new caudal vertebra displays a mosaic of features otherwise restricted to limaysaurine or nigersaurine rebbachisaurids, suggesting a placement basal to these clades, which is the position usually recovered for R. garasbae in phylogenetic analyses. A review of the mid-Cretaceous African sauropod fossil record removes the Cretaceous record of dicraeosaurids from Africa, restricting this clade to a single post-Jurassic occurrence in Argentina. All diagnostic sauropod remains can be attributed to titanosauriforms or rebbachisaurids. Whereas rebbachisaurids were seemingly restricted to northwestern Africa and disappeared post-Cenomanian, titanosauriforms were widespread across the African continent and survived until the latest Cretaceous. The development of the mid-Cretaceous Trans-Saharan Seaway might have acted as a dispersal barrier for rebbachisaurids and other vertebrate groups. In contrast, titanosauriforms might have been able to cross this barrier, but it is possible that they were also unable to disperse, and that northwestern African titanosauriforms were not closely related to taxa from the rest of the African continent. New materials and a better understanding of titanosaur interrelationships will be crucial in teasing these scenarios apart.     

内蒙古的白垩系分布和恐龙类的发展演变

以内蒙古白垩系的分布为导向,重点剖析了白垩纪恐龙化石重要产地的古生态环境及恐龙种类的适应演化。依据燕山运动旋、岩相古地理、生物种群特征,从内蒙古南部到北部按地层年代划分出三个主要恐龙动物群。并进一步分析了食物能量流通、转化的循环系统,对恐龙动物群种类、数量的影响及其以适应环境为特征的繁衍、发展、分化过程,以及早期与晚期恐龙类的相互关系     

河南西峡晚白垩世恐龙蛋化石壳微量元素组成及其对恐龙灭绝的指示意义

恐龙蛋化石是探索恐龙生存和灭绝的重要研究材料,目前对恐龙蛋化石的研究集中在生物学和埋藏特征方面。本文利用电感耦合等离子体发射光谱法(ICP-OES)对采自河南西峡晚白垩世的12枚恐龙蛋化石壳及部分围岩进行分析测试,研究其生命微量元素组成及其与恐龙灭绝的关系。结果表明,恐龙蛋壳中缺乏碳氮磷硫等有机质元素,而主要由钙铝镁铁钾等生命必需元素和锶锰钡镧锌硼钒钴铱等微量元素组成,其中锶和铱均具有明显的超高异常,这可能与地外撞击事件引起生态环境的急剧变化有关。元素的组合规律表明西峡盆地晚白垩世应为干旱、半干旱的气候环境,来自于环境中异常含量的锶和铱共同作用使这一时期该地区大量的恐龙蛋在恐龙体内遭受污染,发育孵化机能受到影响,成为导致盆地内恐龙灭亡的主要原因之一。这一发现为探讨恐龙生活环境变化、灭绝原因以及揭示晚白垩纪古气候提供了重要依据。     

The oldest theropods from the Neuquén Basin: Predatory dinosaur diversity from the Bajada Colorada Formation (Lower Cretaceous: Berriasian–Valanginian), Neuquén,Argentina

Here, we describe new theropod materials (several isolated teeth, an axis, two caudal centra and a proximal left tibia) from the type locality of the Bajada Colorada Formation (Lower Cretaceous, Berriasian–Valanginian). Although fragmentary, the recovered material shows a diverse association of meat-eating dinosaurs for this poorly understood period of time. Three techniques were used to assess the phylogenetic position of the isolated teeth: multivariate (PCA), discriminant and phylogenetic analyses. The morphotypes 1, 2 and 3 (small non-recurved isolated crowns) were regarded as Theropoda indet., as our analyses failed to support a more precise classification. Two large almost complete ziphodont crowns, considered morphotype 4, were identified as belonging to megalosaurid tetanurans by phylogenetic, discriminant and multivariate analyses, thus likely representing the first record of this ancient family in South America, and the youngest worldwide. We refer the axis to a small abelisauroid ceratosaurian based on the following suite of characters; long and pointed epipophyses, a pneumatic foramen in the centrum, the invaginated spinopostzygapophyseal lamina, and the anteroposteriorly long, dorsally convex, and dorsally/posteriorly unexpanded neural spine. The caudal centra can be referred to a theropod, and tentatively to Abelisauroidea, suggesting that they may belong to the same taxon than that represented by the axis. The tibia lacks the incisura tibialis, presents a low, sharp and proximally positioned fibular crest, and has a deep lateral fossa, which is limited dorsally by a coarse, rounded in section and anteriorly directed crest. This combination of features allows to refer it to a large abelisaurid. The Bajada Colorada dinosaur record includes so far a small abelisauroid, a large abelisaurid, a probably medium to large megalosaurid tetanuran, diplodocid and dicraeosaurid sauropods. It shows some similarities with Middle and Upper Jurassic units in central Patagonia, Africa and Portugal, suggesting that no significant dinosaur faunal turnover took place through the Jurassic-Cretaceous event in the southern part of South America.     

长羽毛恐龙及翼龙研究新发现

在江西赣州地区晚白垩世地层中发现的窃蛋龙类化石——赣州华南龙,属于进步窃蛋龙类,其独特的头部特征为研究窃蛋龙类恐龙的颅面演化、古地理分布及古生态环境提供重要信息;在辽西早白垩世义县组地层中发现的大型、前肢短的驰龙类恐龙——孙氏振元龙,为大型、短前肢类型的驰龙类提供羽毛形态学方面的重要信息,为研究驰龙类的多样性、鸟类羽毛以及飞行起源提供了重要依据;在辽西发现的喙嘴龙类翼龙——朝阳东方颌翼龙,是该地区晚侏罗世地层中发现的第一件翼龙标本,不仅填补了时代上的空白,同时对于印证晚侏罗世喙嘴龙类的辐射演化具有重要作用。这些重要发现对于研究窃蛋龙类的演化、驰龙类羽毛演化及鸟类羽毛起源等热点与难点问题提供了重要的参考依据,尤其在发现华南龙的基础上,命名了赣州恐龙动物群。     

Diversity of theropod ootaxa and its implications for the latest Cretaceous dinosaur turnover in southwestern Europe

The scarcity of diagnostic skeletal elements in the latest Cretaceous theropod record of the Ibero-Armorican domain (southwestern Europe) prevents to perform accurate phylogenetic, paleobiogeographic, and diversity studies. In contrast, eggs and eggshells of theropod dinosaurs are relatively abundant and well known in this region from which several ootaxa have been described. Here, we describe the first Late Maastrichtian theropod ootaxon (Prismatoolithus trempii oosp. nov.) from SW Europe and demonstrate that oological record can be used as a proxy for assessing diversity of egg-producers and may help to complement their scarce bone record. The performed analyses indicate that the theropod taxa and ootaxa reach their diversity maxima during the Late Campanian and start to decrease near the Campanian–Maastrichtian boundary at both global and regional scales. The oological diversity of theropods in the Ibero-Armorican domain is consistent with the theropod diversity identified at high taxonomic level. Two distinct assemblages of theropod ootaxa can be recognized in the latest Cretaceous of the Ibero-Armorican domain. Their temporal transition can be correlated with other dinosaur faunal changes recorded in the region. This faunal turnover took place around the Early–Late Maastrichtian boundary, involving ornithopods, sauropods, ankylosaurs and, according to the present results, theropods as well.     

Statistical Approach for Classification of Dinosaur Eggs from the Heyuan Basin at the Northeast of Guangdong Province

The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, outer surface texture, and shell thickness) of 461 eggs were analyzed using non-destructive techniques and subjected to statistical analyses in order to assess their diversity and taxonomic affinities. Three types (1, 2 and 3) of eggs were discerned based on shape and outer surface morphology. Type 1 eggs are spherical to ellipsoidal in shape and have a rough surface. Three subtypes (Type 1-A-1, 1-A-2, and 1-B) are apparent from scatter plots and cluster analyses of egg diameters and shell thickness. Type 2 eggs are elongate with linear ornamentation on the surface, and are comparable to eggs that belong to the oofamily Elongatoolithidae. Type 3 eggs are elongate with a smooth surface, and are assigned to the oofamily Prismatoolithidae. Macromorphological features of the various egg types suggest that Type 1 could have been laid by ornithischian, sauropod or therizinosaur dinosaurs, Type 2 by oviraptorids, and Type 3 by troodontids. This study represents the first comprehensive statistical analysis of macrofeatures of dinosaur eggs, and reveals taxonomic diversity in the dinosaurs that were laying eggs in the Upper Cretaceous Heyuan area heretofore unrecognized in skeletal remains.     

中国南方首次发现的基干禽龙类化石新属种

广西壮族自治区扶绥县那派盆地早白垩世新隆组中产有包含蜥脚类、兽脚类、鸟脚类、疑似鹦鹉嘴龙类的恐龙动物群,但鸟脚类的属种鉴定尚不能进一步确认.最近发现于那派盆地新的鸟脚类肠骨、坐骨化石材料,显示出基干禽龙类的典型形态,其特征又不同于该类群其他已知属种,应代表禽龙类一新属新种,被命名为广西那派龙Napaisaurus gu...     

A New Theropod Dinosaur from the Middle Jurassic of Lufeng, Yunnan, China

A new theropod dinosaur,Shidaisaurusjinae gen.et sp.nov.,has been described on the basis of an incomplete skeleton.The specimen was found near the base of the Upper Lufeng Formation(early Middle Jurassic)in Yunnan,China.It is the first theropod dinosaur from the Middle Jurassic of Yunnan.Shidaisaurus jinae is distinguishable from other Jurassic theropods by certain features from the braincase,axis,and pelvic girdle.The absence of any pleurocoels in the axis or in any anterior dorsal vertebrae suggests that the new Lufeng theropod is relatively primitive and more plesiomorphic than most of the Middle to Late Jurassic theropods from China.Most Chinese taxa of Jurassic theropod dinosaurs have not been well described;a further detailed study will be necessary for us to determine their phylogenetic relationships with Shidaisaurus jinae.