Publications by authors named "Caizhi Shen"

Enantiornithes are the most successful early-diverging avian clade, their fossils revealing important information regarding the structure of Cretaceous avifaunas and the parallel refinement of flight alongside the ornithuromorph lineage that includes modern birds. The most diverse recognized family of Early Cretaceous enantiornithines is the Bohaiornithidae, known from the Jehol Biota in northeastern China. Members of this clade enhance our understanding of intraclade morphological diversity and elucidate the independent evolution of this unique lineage.

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The Tapejarinae are edentulous pterosaurs that are relatively common in Cretaceous continental deposits in South America, North Africa, Europe, and China (mostly Early Cretaceous). The Chinese Jiufotang Formation is particularly rich in tapejarine specimens, having yielded over 10 described specimens and dozens of undescribed ones. For the Jiufotang Formation, a total of seven nominal tapejarid species and two genera have been proposed.

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Anurognathids are an elusive group of diminutive, potentially arboreal pterosaurs. Even though their monophyly has been well-supported, their intrarelationships have been obscure, and their phylogenetic placement even more. In the present work, we present a new genus and species from the Middle-Late Jurassic Tiaojishan Formation, the third nominal anurognathid species from the Jurassic of China.

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Pterosaurs, which lived during the Mesozoic, were the first known vertebrates to evolve powered flight. Arboreal locomotion has been proposed for some taxa, and even considered to have played a role in the origin of pterosaur flight. Even so, there is still need for comprehensive quantitative ecomorphological analyses.

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Most birds sit on their eggs during incubation, a behaviour that likely evolved among non-avian dinosaurs. Several 'brooding' specimens of smaller species of oviraptorosaurs and troodontids reveal these non-avian theropods sat on their eggs, although little is known of incubation behaviour in larger theropod species. Here we examine egg clutches over a large body size range of oviraptorosaurs in order to understand the potential effect of body size on incubation behaviour.

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Article Synopsis
  • A new oviraptorid dinosaur called Corythoraptor jacobsi has been discovered in Ganzhou from the Late Cretaceous, increasing the region's known oviraptorid diversity to seven species.
  • Corythoraptor is identified by its unique cassowary-like crest, long neck, and specific vertebra structure, and its analysis suggests it's closely related to Huanansaurus.
  • Histological studies indicate that Corythoraptor was an immature dinosaur, estimated to be around eight years old, and its casque likely served multiple purposes including display and communication during mating.
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Article Synopsis
  • The discovery of numerous dinosaur eggs in Henan Province, China resulted in the return of a significant fossil specimen that includes a partial clutch of large Macroelongatoolithus eggs and a small theropod skeleton.
  • This specimen has been identified as the eggs and embryo of a new species called Beibeilong sinensis, representing the first known connection between caenagnathid skeletal remains and their eggs.
  • While similar to oviraptorids, Beibeilong eggs are larger and suggest a body size akin to a giant caenagnathid, implying that these dinosaurs were more common in the early Late Cretaceous than previously recognized, especially considering the limited finds of their remains.
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Oviraptorosaurs are a bizarre group of bird-like theropod dinosaurs, the derived forms of which have shortened, toothless skulls, and which diverged from close relatives by developing peculiar feeding adaptations. Although once among the most mysterious of dinosaurs, oviraptorosaurs are becoming better understood with the discovery of many new fossils in Asia and North America. The Ganzhou area of southern China is emerging as a hotspot of oviraptorosaur discoveries, as over the past half decade five new monotypic genera have been found in the latest Cretaceous (Maastrichtian) deposits of this region.

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Although there are nine genera of ctenochasmatoids reported from the Jehol Biota, at present each is known from a specimen that has either a skull or a relatively complete postcranial skeleton. A nearly complete juvenile specimen of Gladocephaloideus from the Lower Cretaceous Jiufotang Formation of Sihedang, Lingyuan of Liaoning Province is the most complete ctenochasmatoid preserved to date with a skull and postcranial skeleton. Based on the holotype (IG-CAGS 08-07) and the nearly complete new specimen (JPM 2014-004), the diagnosis of Gladocephaloideus is amended: approximately 50 teeth in total with sharp tips; small nasoantorbital opening, occupying approximately 13% of total skull length; ratio of prenarial rostrum length to skull length approximately 0.

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Psittacosaurus is one of the most abundant dinosaurs known, which allows for extensive study of its growth and form. Previous studies have evaluated growth trajectories of Psittacosaurus using bone histology. However, we present the first study of Psittacosaurus comparative juvenile histology and describe the histology of Psittacosaurus within its first year of life based on multiple sections taken from an exquisite monospecific assemblage of juveniles from the Yixian Formation in Liaoning, China.

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The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally.

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We report on a new specimen of Longipteryx chaoyangensis from the Lower Cretaceous Yixian Formation in Chaoyang, Liaoning Province, China. The new material preserves previously unknown tooth crenulations. This is the first recognized tooth crenulations within Aves.

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