Here we describe an incomplete dinosaur clutch with three broken eggs and seven prints discovered in Wuning County,Jiangxi Province,that can be referred to Coralloidoolithus shizuiwanensis based on the following features:the eggs are nearly spheroid and arranged tightly and irregularly in the clutch,the eggshell thickness ranges 2.76-2.97 mm,the horizontal accretion lines are almost evenly distributed throughout the eggshell,and the secondary eggshell units are distributed in the medial and outer zones of the columnar layer.This egg clutch of Coralloidoolithus shizuiwanensis represents the first discovery of dinosaur eggs in Wuning County,and shows the age of the strata containing the dinosaur eggs in this area should be Late Cretaceous.

Here we describe a partially-preserved dinosaur clutch with twelve nearly complete eggs discovered in Shanggao County,Jiangxi Province that can be assigned to Coralloidoolithus shizuiwanensis.These dinosaur eggs are nearly spheroid in shape,with an average polar axis of l 1.8 cm and an average equatorial diameter of 9.8 cm.The eggshell has a maximum thickness of about 2.5 mm and is composed of a thin cone layer and a multilevel columnar layer,the latter of which can be divided into inner,medial and outer zones.There are dense horizontal growth lines in the inner zone,lamellar and speckled dark materials in the medial zone,and the secondary eggshell units are distributed in the medial and outer zones.According to this discovery,we revise the main taxonomic characteristic of Coralloidoolithus in the Stalicoolithidae to be the loose and dark materials in the medial zone of the columnar layer.This discovery not only extends the paleogeographic distribution of Coralloidoolithus shizuiwanensis,but also provides comparative evidence of the Late Cretaceous strata in the Shanggao red basin.

报道了新疆哈密南湖戈壁首次发现的恐龙蛋,包括长形长形蛋(Elongatoolithus elongatus)和椭圆形蛋未定种(Ovaloolithus oosp.).这些恐龙蛋的发现不仅扩展了长形蛋类和椭圆形蛋类的古地理分布,而且表明南湖戈壁含蛋岩层地质时代为晚白垩世末期;该地层是否可与吐鲁番盆地的苏巴什组进行对比还有待进一步工作确认.

Whether or not nonavian dinosaur biodiversity declined prior to the end-Cretaceous mass extinction remains controversial as the result of sampling biases in the fossil record, differences in the analytical approaches used, and the rarity of high-precision geochronological dating of dinosaur fossils. Using magnetostratigraphy, cyclostratigraphy, and biostratigraphy, we establish a high-resolution geochronological framework for the fossil-rich Late Cretaceous sedimentary sequence in the Shanyang Basin of central China. We have found only three dinosaurian eggshell taxa (Macroolithus yaotunensis, Elongatoolithus elongatus, and Stromatoolithus pinglingensis) representing two clades (Oviraptoridae and Hadrosauridae) in sediments deposited between ∼68.2 and ∼66.4 million y ago, indicating sustained low dinosaur biodiversity, and that assessment is consistent with the known skeletal remains in the Shanyang and surrounding basins of central China. Along with the dinosaur eggshell records from eastern and southern China, we find a decline in dinosaur biodiversity from the Campanian to the Maastrichtian. Our results support a long-term decline in global dinosaur biodiversity prior to 66 million y ago, which likely set the stage for the end-Cretaceous nonavian dinosaur mass extinction.

This study describes a new member of Similifaveoloolithidae from the Upper Cretaceous Zhoutian Formation of Jiangxi, China. The new ootaxon, Wormoolithus luxiensis oogen. et oosp. nov., is erected based on eggs collected from a partial clutch and represents the second oogenera of Similifaveoloolithidae. Wormoolithus shares some unique features with Similifaveoloolithus such as irregularly branched eggshell units, irregular cavities in the inner part of eggshell that are worm-like in tangential view and oblique pore canals in the outer part of the eggshell that show honeycomb-like structure in tangential view. And it is distinguished from the latter by longer polar axis and equatorial diameter and absence of compact layer. Although the clutch is not complete, the preserved parts show that the eggs are closely stacked in the nest. In addition, clay minerals that occur in pores and a high estimated water vapour conductance indicate a humid burial nest microenvironment.

河南淅川盆地的恐龙蛋发现与研究始于1974年,淅川盆地恐龙蛋具有非常高的多样性,共计发现4个蛋科、6个蛋属、6个蛋种,尤其以树枝蛋类最为丰富。近年来,河南地质博物馆对全省地质遗迹调查过程中,在淅川盆地再次有新的恐龙蛋类型的发现,本文对其中的部分标本进行记述,根据壳单元呈多分叉的不规则树枝状,蛋壳厚度为1.62～1.74 mm,锥体间隙明显,壳单元自锥体上部开始出现分枝,蛋壳中部大多具有3～4个分枝,近蛋壳外表面形成融合层,蛋壳具有复杂的气孔系统等特征区别于其他类型的树枝蛋类,建立一新蛋种:大石桥树枝蛋（Dendroolithus dashiqiaoensis oosp. nov.）。通过对淅川盆地恐龙蛋分类与对比、不同类型恐龙蛋在地层中的分布研究,将有助于盆地内白垩纪红层的划分,也将为秦岭东段各盆地中同一时期红层的划分与对比、古地理、古环境和古气候等研究提供更加翔实的古生物学证据。

辽宁省是我国最早发现恐龙蛋的地区,这里还出土了目前我国地质时代最早的恐龙蛋.辽宁发现的恐龙蛋数量虽不算多,但都意义非凡. 2019年7月22日,中国地质调查局沈阳地质调查中心张超工程师和吉林大学楼仁兴副教授带领学生,在辽宁省铁岭市昌图县昌林加气站附近对晚白垩世泉头组地层(距今0.9亿～1亿年)开展沉积特征及岩相古地理研究.该地点的泉头组地层出露较好,产状(层面在空间上的延伸方位及其倾斜程度)近水平,中国地质调查局沈阳地质调查中心昌图项目组(以下简称:项目组)在这里进行地层垂向剖面测制等调查工作,不曾想有了意外发现.

The first clutch of Stalicoolithus shifengensis is described here.This incomplete dinosaur egg clutch in which three nearly complete eggs and two egg prints were preserved was discovered in the red deposits of the Sanshui Formation at a construction site near the sluice of North Village,Dali Town,Nanhai District,Foshan City,Guangdong Province,China.The eggs in the clutch are stacked with various ranges.Based on the characteristics of the eggshell,these eggs can be assigned to S.shifengensis.The discovery ofS.shifengensis in the Sanshui Formation complements the clutch information about the oospecies as well as expands its paleogeographic distribution,and sets the foundation for discussing the diversity of dinosaur eggs in the Sanshui Basin.

Here we discribe a new ootypes of prismatoolithids found from the Late Cretaceous Jiangjunding Formation in the Laiyang Basin, Shandong Province. On the basis of characters such as elongate ovoids, smooth eggshell surface, relatively thinner eggshell thickness, prismatic eggshell units, slender pores in radial section of eggshell and little pores with round or irregular shapes in tangeital section of eggshell, we erect one new oogenus and one new oospecies: Laiyangoolithus lixiangensis oogen. et oosp. nov. The discovery of L. lixiangensis not only enriches the diversity and composition of the Laiyang Dinosaur Egg Fauna, but the paleogeographic distribution of primatoolithids as well. In addition, it provides more paleontological materials for the study of the diversity and paleogeographic distribution of troodontids in China.

Here we discribe a new ootypes of prismatoolithids found from the Late Cretaceous Jiangjunding Formation in the Laiyang Basin, Shandong Province. On the basis of characters such as elongate ovoids, smooth eggshell surface, relatively thinner eggshell thickness, prismatic eggshell units, slender pores in radial section of eggshell and little pores with round or irregular shapes in tangeital section of eggshell, we erect one new oogenus and one new oospecies: Laiyangoolithus lixiangensis oogen. et oosp. nov. The discovery of L. lixiangensis not only enriches the diversity and composition of the Laiyang Dinosaur Egg Fauna, but the paleogeographic distribution of primatoolithids as well. In addition, it provides more paleontological materials for the study of the diversity and paleogeographic distribution of troodontids in China.

A new ootype collected from the Upper Cretaceous Lijiacun Formation in the Shangdan Basin, Shaanxi Province is described in this paper. Based on general external shape, size, eggshell thickness and honeycomb-like eggshell microstructure, eggs are referable to the oofamily Faveoloolithidae. Compared with other members of Faveoloolithidae, specimens described in this paper show special characteristics: adjacent pores are usually separated by two eggshell units between which often develop interspaces; columnar eggshell units are relatively closely arranged in radial view. According to these characteristics, we erect a new oogenus and a new oospecies: Duovallumoolithus shangdanensis oogen. et oosp. nov. The new discovery expands the diversity of Faveoloolithidae.