A new oospecies of Similifaveoloolithidae from the Xiuning Basin,Late Cretaceous of Anhui,China

Well-preserved dinosaur eggs from the Cretaceous Huizhou Formation in the Xiuning Basin, Anhui Province, China, are analysed in this paper. We describe a new oospecies, Similifaveoloolithus qiyunshanensis, based on several distinct characters of external morphology, size, eggshell thickness, and internal microstructure. Radial sections of this new oospecies show branched eggshell units with a fused layer near the outer surface, while numerous irregular pores and cones constitute a honeycomb pattern in tangential sections. The discovery of S. qiyunshanensis expands the distribution of Similifaveoloolithidae dinosaur eggs in China and provides new fossils for researching dinosaur eggshell formation mechanisms which are different from those of the currently known oofamilies. The dinosaur-egg-bearing strata in the Huizhou Formation have been dated to the early Late Cretaceous (Cenomanian-Turonian) on the basis of a similar dinosaur egg assemblage in the Tiantai Basin in Zhejiang Province. The eggs described in this paper are thought to have been laid in a buried nest while enrichment of trace elements in eggshells may have been caused by their ingestion into the body of the dinosaur producer. We suggest that the paleoclimate of this habitat was semi-arid to arid and that this environment was favourable for the preservation of eggs.http://zoobank.org/LSIDurn:lsid:zoobank.org:pub:9D63A51F-5A4B-4249-901D-42A33E9FA933     

A new egg with avian egg shape from the Upper Cretaceous of Zhejiang Province,China

A new egg is described from the Upper Cretaceous lacustrine deposit of the Chichengshan Formation in the Tiantai Basin, Zhejiang Province, southeast China. The new specimen shares eggshell micro-features with members of the oofamily Stalicoolithidae, Paraspheroolithus of the oofamily Spheroolithidae and Mosaicoolithus (oofamily indet.), with barrel-shaped cones, prolatocanaliculate pore system, horizontal accretion lines and light stripes throughout the eggshell. However, the new egg differs from the aforementioned ootaxa by its small size and asymmetrical shape, revealing new morphological variation among eggs with microstructure similar to that of Paraspheroolithus, Mosaicoolithus and Stalicoolithidae. We refer the new egg to a new oogenus and oospecies, thus increasing the diversity of the Tiantai Basin oofauna. The Tiantai Basin has yielded a variety of dinosaur eggs and one turtle clutch. Comparatively, the new egg is surprisingly small and ovoid, a morphology usually associated with avian eggs, although the absence of a squamatic layer excludes the egg from being referred to this group.     

江西萍乡地区晚白垩世副蜂窝蛋类一新蛋种

依据采自江西省萍乡地区上白垩统周田组的恐龙蛋化石,记述了蜂窝蛋科(Faveoloolithidae)副蜂窝蛋属(Parafaveoloolithus)一新蛋种。材料包括一枚较完整的蛋和若干破碎蛋壳。根据蛋壳弦切面呈蜂窝状结构,径切面蛋壳中、上部蛋壳局部呈现由6~10个以上壳单元成群聚集一起等特征,将其订为一新蛋种——萍乡副蜂窝蛋(Parafaveoloolithus pingxiangensis oosp.nov.)。     

Small Theropod Teeth from the Late Cretaceous of the San Juan Basin,Northwestern New Mexico and Their Implications for Understanding Latest Cretaceous Dinosaur Evolution

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs. Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns. We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian – Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas. The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately co-eval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species. A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction.     

浙江天台盆地晚白垩世网形蛋类新类型及网形蛋类的分类订正(英文)

记述了产自浙江省天台盆地的网形蛋类新材料,建立一新蛋属——拟网形蛋属(Paradictyoo lithusoogen.nov.),两个新蛋种:庒前拟网形蛋(Paradictyoolithus zhuangqianensis oogen.etoosp.nov.)和下西山拟网形蛋(P.xiaxishanensis oogen.et oosp.nov.)。在此基础上,重新系统描述其他已知4种网形蛋属成员的结构特征,并对网形蛋类的分类进行了订正:网形蛋属(Dictyoolithus)仅保留红坡网形蛋(D.hongpoensis Zhao,1994)一个蛋种;建立一新蛋属:原网形蛋属(Protodictyoolithus oogen.nov.),将发现于河南西峡盆地的内乡网形蛋(D.neixiangensis Zhao,1994)和发现于山东莱阳盆地的蒋氏网形蛋(D.jiangi Liu&Zhao,2004)分别修订为:内乡原网形蛋(修订种)(Protodictyoolithus neixiangensis(Zhao,1994)comb.nov.)和蒋氏原网形蛋(修订种)(P.jiangi(Liu&Zhao,2004)comb.nov.);此外,发现于吉林公主岭早白垩世的公主岭网形蛋(D.gongzhulingensis Wang et al.,2006)并不属于网形蛋类,而应归入似蜂窝蛋类(Similifaveoolithus),将其修订为公主岭似蜂窝蛋(修订种)(Similifaveoolithus gongzhulingensis(Wangetal.2006)comb.nov.)。     

Unusually thick dinosaur eggshell fragments from the Spanish Late Cretaceous

Fieldwork carried out recently in the southeastern branch of the Iberian Range (Valencia Province, Spain) has led to the collection of a large volume of dinosaur eggshell fragments of unusual thickness. These specimens, up to 4.9 mm thick, were recovered from palustrine grey marls of the upper Campanian-lower Maastrichtian Sierra Perenchiza Formation, which comprises a wetland paleoenvironment deposit. These eggshell fragments have a characteristic compactituberculate ornamentation, dinosauroid-spherulitic organisation, and exhibit a complex canaliculate respiratory system. The external tuberculate surface of the shell as well as the internal microstructure enable referral to Megaloolithus aff. siruguei, the most common megaloolithid oospecies known from the Iberian Peninsula and southern France. The biostratigraphic range of M. siruguei matches the temporal distribution of titanosaurid dinosaurs across the Iberian Range, tentatively considered to be potential producers.     

A new crocodylian from the late Maastrichtian of Spain: implications for the initial radiation of crocodyloids

Background

The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America.

Methodology/Principal Findings

The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at −67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea.

Conclusions/Significance

The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian.     

The first record of a dinosaur from Bulgaria

Mateus, O., Dyke, G.J., Motchurova-Dekova, N., Kamenov, G.D. & Ivanov, P. 2010: The first record of a dinosaur from Bulgaria. Lethaia, Vol. 43, pp. 88–94.
A portion of a left humerus from the Upper Maastrichtian of Vratsa district (NW Bulgaria) is shown to be from a non-avian theropod dinosaur: this is the first record of a dinosaur from Bulgaria. We describe this bone, suggest that it most likely pertains to an ornithomimosaur, and discuss the fossil record of other similar taxa of Late Cretaceous age that have been reported from Europe. To investigate the taphonomy of this fossil, rare earth element (REE) analysis is combined with strontium (Sr) isotope data to confirm that this Bulgarian dinosaur bone was initially fossilized in a terrestrial environment, then later re-worked into late Maastrichtian marine sediments. □ Bulgaria , Dinosauria , Late Cretaceous , Ornithomimosauria , rare earth elements , Sr isotopes , taphonomy , Theropoda .     

Palaeoenvironmental and palaeobiogeographical implications of fossil seeds and charophytes from the Lameta Formation (Late Cretaceous), Jabalpur,Madhya Pradesh,India

A Late Cretaceous fossil flora composed of five fossil seed genera and two charophyte genera was discovered and reported here from the siltstone and green marl band of the Lameta Formation at the Chui Hill section and the Chhota Simla Hill section in the Jabalpur area. On the basis of comparative studies, including thin-section and XRD analysis, the palaeoenvironment is deduced to be arid to semi-arid fluvial-lacustrine. The recovered flora suggests Laurasian palaeobiogeographic affinity and shows the dispersal route from Europe to India via Africa.     

The West Gondwanan Occurrence Of The Hybodontid Shark Priohybodus, And The Late Jurassic–Early Cretaceous Age Of The Tacuarembó Formation, Uruguay

Priohybodus cf. P. arambourgi is reported for the first time from the Tacuarembó Formation of Uruguay. This species is a hybodontid shark known previously only from Upper Jurassic and Lower Cretaceous deposits of Saharan Africa and the Arabian Peninsula. The material (22 isolated teeth and a dorsal fin spine) was found in a thin bone bed, associated with abundant bone fragments, scales and teeth of semionotiform fishes and theropod dinosaurs. Until now, the age of the Tacuarembó Formation has been difficult to determine because its fossil content lacked useful biostratigraphic indicators. The finding of Priohybodus cf. P. arambourgi in that unit greatly expands the palaeobiogeographic range of the species, and allows us to propose a Late Jurassic–Early Cretaceous age for the Tacuarembó Formation.     

Latest Cretaceous hadrosauroid (Dinosauria: Ornithopoda) remains from Bulgaria

Disarticulated dinosaur bones have been discovered in a fossiliferous lens in the Labirinta Cave, southwest of the town of Cherven Bryag, in NW Bulgaria. This cave is formed within marine limestones belonging to the Kajlâka Formation of Latest Cretaceous age. Associated fossils and Sr isotopy suggest that the fossiliferous sediments belong to the uppermost part of the Upper Maastrichtian. The dinosaur bones discovered in this lens include the distal portion of a left femur, a right tibia, the proximal part of a right fibula, a left metatarsal II, the second or third phalanx of a left pedal digit IV, the proximal end of a second metacarpal, and a caudal centrum. All the bones undoubtedly belong to ornithopod dinosaurs and more accurately to representatives of the hadrosauroid clade. All belong to small-sized individuals, although it cannot be assessed whether they belong to juveniles or small-sized adults, pending histological analyses. Hadrosauroid remains have already been discovered in Late Maastrichtian marine sediments from western, central and eastern Europe, reflecting the abundance of these dinosaurs in correlative continental deposits. Indeed, hadrosauroids were apparently the dominating herbivorous dinosaurs in Eurasia by Late Maastrichtian time.     

Titanosaur eggshells from the Tremp Formation (Upper Cretaceous,Southern Pyrenees,Spain)

Hundreds of megaloolithid eggshells have been found at the Costa de la Coma site (Tremp Fm, South-Central Pyrenees, Spain), the microstructural features (spherulitic eggshell units, thickness, ornamentation and pore system) of which agree with the Megaloolithus oogenus diagnosis. Comparisons with other megaloolithids from the Tremp Basin, southern France and South America, however, showed that these eggshells share many features with the South American oospecies Megaloolithus patagonicus. A cladistic analysis of the qualitative eggshell features of the main dinosaur taxa was performed. The results grouped the Costa de la Coma eggshells with Megaloolithus patagonicus, forming a clade separated from other megaloolithids, and revealed a polytomy of megaloolithids (associated with sauropods) and spheroolithids (associated with hadrosaurs). The finding of Megaloolithus cf. patagonicus in the Tremp Fm agrees with skeletal evidence provided by four indeterminate titanosaur forms from the Formation's late Cretaceous deposits. Other Megaloolithus oospecies of the Tremp Fm may belong to hadrosaurs, the skeletal remains of which are also abundant in the Tremp Basin.     

山东莱阳晚白垩世恐龙蛋化石一新类型

山东莱阳是中国最早发现的含有丰富的晚白垩世恐龙及恐龙蛋化石产地。上个世纪50～60年代,周明镇(1951,1954)及杨钟健(1954,1959,1965)对莱阳首次发现的恐龙蛋化石进行了研究。1974年,赵资奎、蒋元凯在前人工作基础上,采用显微镜技术方法重新研究了莱阳恐龙蛋壳的显微结构,结果发现它们的显微结构有很大差异。根据赵资奎(1975)提出的恐龙蛋分类方法(Parataxonomy),将莱阳地区已发现的恐龙蛋分别归入圆形蛋科(spheroolithidae)、椭圆形蛋科(Ovaloolithidae)和长形蛋科(Elongatoolithidae)等3个科,共5个属12个种(赵资奎,1979,1993)。最近,大连自然博物馆在整理馆存的化石标本时,发现有4枚形状为扁圆形的恐龙蛋化石是1973年10月从山东莱阳将军顶采集到的。根据目前有关莱阳地区晚中生代地层划分修订的标准(胡承志等,2001),这些标本的出土层位应为上白垩统王氏群将军顶组。我们的初步观察表明,蛋化石的形状、大小及其蛋壳显微结构特征与上述已报道的莱阳恐龙蛋3个类群的明显不同,在此简单记述,以期对莱阳地区晚白垩世恐龙蛋群的综合研究提供些许资料。     

Myliobatid and pycnodont fish from the Late Cretaceous of Central India and their paleobiogeographic implications

Bulk sampling from Upper Cretaceous (Maastrichtian) Deccan volcano-sedimentary sequences at Kisalpuri (District Dindori, Madhya Pradesh) and Pisdura–Dongargaon (Chandrapur District, Maharashtra) in Peninsular India has yielded the dental remains of myliobatid and pycnodont fish. This fish fauna comprises Igdabatis indicus, Pycnodontoidea indet. and Pycnodontidae indet., and resembles assemblages known from Upper Cretaceous deposits in Africa and Europe. While paleobiogeographically speaking, the presence of Igdabatis suggests a series of shallow marine dispersals that may have occurred between Africa and India, possibly along the margins of the Kohistan–Ladakh island arc during the latest Cretaceous; the record of pycnodont fish favours instead a Gondwanan dispersal event.     

A new Upper Cretaceous titanosaur nesting site from La Rioja (NW Argentina), with implications for titanosaur nesting strategies

Cretaceous titanosaur nesting sites are currently known only from Europe, Asia and South America. In the latter, only the Auca Mahuevo and Sanagasta nesting sites have been confidently assigned to this clade of sauropod dinosaurs. Here we report the discovery of the first eggs and egg clutches found at Tama, a new Upper Cretaceous fossiliferous locality in the Los Llanos Formation, Sierra de Los Llanos (La Rioja, NW Argentina). At least five egg clutches, several partially preserved, isolated eggs and many eggshell fragments were discovered in a single outcrop of a sandstone horizon which represents a cumulative palaeosol profile. Although the mechanical and digital preparation of eggs did not reveal any embryonic remains in ovo, the morphology of the eggs and eggshells closely matches that of titanosaur eggs and eggshells found worldwide. The morphology and spatial grouping of the titanosaur eggs from Tama, along with geological observations support a burrow‐nesting strategy for these dinosaurs. Although the Sanagasta and Tama eggs were found in the same stratigraphical unit and share several morphological characters, they clearly differ in shell thickness and egg size. This, coupled with the interpretation of different sedimentary contexts for these nesting sites, strongly suggests that at least two different titanosaur species nested in La Rioja during the Late Cretaceous, using different nesting strategies. The occurrence of this new titanosaur nesting site in a semiarid palaeoenvironment represents an interesting case study for the reproductive biology of the titanosaur dinosaurs, particularly their labile nesting behaviour.     

Paleoenvironmental and paleobiogeographical implications of the microfossil assemblage from the Late Cretaceous intertrappean beds of the Manawar area,District Dhar,Madhya Pradesh,Central India

Abstract

An assemblage of microfossils consisting of non-marine ostracods (Cypridopsis, Gomphocythere, Zonocypris, Eucypris, and Frambocythere), charophyte gyrogonites (Platychara), molluscs (Viviparus, Valvata, and Lymnaea), and fish remains (mainly Phareodus), is here reported from a new intertrappean locality near the town of Manawar, District Dhar, Madhya Pradesh, Central India. The biotic component recovered suggests a Late Cretaceous (Maastrichtian) age for the intertrappean deposit near Manawar. Paleoenvironmentally, the overall biotic assemblage recovered indicates the presence of a freshwater palustrine/lacustrine depositional system connected to a low energy stream/river. Paleobiogeographically, the known high diversity of ostracod genera, especially Eucypris, Cypridopsis, and Gomphocythere, hints at endemism within the Indian Subcontinent during the Late Cretaceous (Maastrichtian). However, the cosmopolitan distribution of the charophyte genus Platychara in the K-Pg interval across the globe (Africa, Europe, and America) and its absence in the Upper Cretaceous of China and Mongolia is quite intriguing.     

New Late Cretaceous dinosaur findings from northwestern Transylvania (Romania)

In 1905, Nopcsa tentatively identified a fragmentary rib from the Jibou Formation at Someş Odorhei as belonging to an ornithopod dinosaur. Therefore, he concluded that the base of this formation is Late Cretaceous, but this hypothesis was subsequently ignored or rejected by other authors. New dinosaur bones discovered in this locality by new excavations are here interpreted as belonging to the euornithopod Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. The base of the Jibou Formation can therefore be regarded as Maastrichtian, correlative to the Sânpetru Formation and to the middle member of the Densuş Ciula Formation from the Haţeg Basin, as well as the base of the Şard Formation in the southwestern Basin of Transylvania, in the Alba Iulia area. The presence of Zalmoxes at Someş Odorhei also confirms the northeastern extension for the ‘Haţeg Island’ in Transylvania.     

内蒙古巴音满都呼晚白垩世棱齿龙蛋化石的发现

本文记述的恐龙蛋化石标本,采自内蒙古乌拉特后旗巴音满都呼上白垩统牙道黑达组中。蛋化石在蛋窝中排列的方式和蛋壳的显微结构特征与北美发现的含有可鉴定为棱齿龙胚胎骨骼的蛋化石基本相似,但还有一些差别,如蛋壳外表面不具纵向细纹,柱状层中鱼骨型纹饰不明显等。因此,应为棱齿龙科中另一新的属种代表。     

Review of Japanese Dinosaur Track Localities: Implications for Ichnotaxonomy,Paleogeography and Stratigraphic Correlation

Nine dinosaur ichnospecies from the Lower Jurassic to Upper Cretaceous of Japan, including two that are new, are described herein. The new ichnotaxa are Asianopodus pulvinicalx ichnogen. et ichnosp. nov. and Schizograllator otariensis ichnosp. nov. The Japanese ichnotaxa are allied to Lower Jurassic ichnospecies in South China, North America, Western Europe and South Africa, and Upper Jurassic to Lower Cretaceous ichnospecies from Southeast and East Asia. This suggests they were part of a global ichnofauna before continental drift began in the Middle Jurassic, leading to the development of a more endemic dinosaur fauna in the Cretaceous. At least two assemblages, an ornithopod-gracile-toed theropod-dominated community, in northeastern Asia, and a robust theropod- and sauropod-dominated community in the southern part of the continent, existed in the Cretaceous. This parallels North American dinosaur distribution patterns in the Cretaceous and seems to be a reflection of paleolatitudinal controls.     

A new peculiar dinosaur egg,Sankofa pyrenaica oogen. nov. oosp. nov. from the Upper Cretaceous coastal deposits of the Aren Formation,south‐central Pyrenees,Lleida, Catalonia,Spain

Abstract: A new type of small, ovoid dinosaur egg, Sankofa pyrenaica oogen. nov. oosp. nov., with a prismatic type eggshell is described from upper Cretaceous (upper Campanian–Maastrichtian) deposits of the Montsec area, South Pyrenean Central Unit, Lleida, Catalonia, Spain. This egg type was sub‐vertically laid in only two rich monospecific sites of a single stratigraphic layer from coastal deposits of the Aren Formation, interpreted as an emerged beach ridge of a barrier island – lagoon depositional system. The size and shape of these eggs with their asymmetric poles are roughly similar to modern hen eggs, which is unusual in the Cretaceous fossil egg record. Its phylogenetic position clusters with bird and Troodontid eggs. A morphospace analysis of egg shapes shows the similarity of the new egg to a Campanian fossil bird egg from Argentina, both being intermediate between modern‐bird eggs and extinct nonavian theropod eggs. However, the eggshell microstructure of Sankofa pyrenaica differs from that of bird eggs in its incipient squamatic texture. It has a peculiar pattern of interlocking small crystals in the middle of the palisade layer, instead of the thick squamatic structure commonly present in modern avian eggshells. This new egg type is attributed to a small theropod, probably with a single oviduct like birds and whose mosaic distribution of features is a combination between that of birds and nonavian theropods. This enhances the arguments supporting the close phylogenetic relationships between both groups.