The Upper Cretaceous of Tantou Basin in western Henan has yielded many vertebrate fossils,which are featured by several non-avian dinosaurs.Meanwhile,studies on their eggs were yet inadequate though many eggshells have been reported.The newly discovered material 41HV0199 was excavated from the Upper Cretaceous Qiupa Formation in 2021.The block preserves eight complete eggs arranged in two partial rings that form a partial clutch,and there are some scattered eggshells preserved closely with the block,showing a concave-up to concave-down ratio of 54.5:45.5,which indicates that the scattered eggshells come from the clutch and the clutch had been partially broken before it was buried.Based on morphological and microstructural characteristics,the eggs and eggshells can be assigned to Macroolithus yaotunensis(Elongatoolithidae),an oospecies known to be related to oviraptorids,which leads Yulong mini to be its probable producer.Besides,some eggshells show microstructural signs indicating egg retention,which marks the second example of egg retention in the oofamily Elongatoolithidae.

汝阳盆地是豫西地区的一个中—新生代断陷盆地,自2006年以来发现了一个以巨型蜥脚类恐龙为代表的恐龙动物群.本文描述了近期发现于汝阳盆地下白垩统郝岭组中的若干恐龙蛋蛋壳碎片.基于以下对蛋壳宏观形态和显微特征的分析,这些蛋壳碎片可以归入长形蛋科(Elongatoolithidae)的长形蛋属(Elongatoolithus):蛋壳外表面具分散瘤点状或线性脊状的纹饰;蛋壳自内而外分为锥体层和柱状层,二层之间的界线不清晰;锥体层中锥体排列紧密;柱状层中具波浪状的平行生长纹.这一发现代表了长形蛋属在早白垩世地层中的首次记录,进一步拓展了该蛋属的地史和古地理分布.由以往已知的化石关联推测,这些蛋壳可能与该层位中的窃蛋龙类如刘店洛阳龙(Luoyanggia liudianensis)等具有相关性,表明汝阳盆地在早白垩世晚期具有适宜该类恐龙生存与繁殖的环境.

In 2007, a clutch of approximately 30 fossil eggs reported from the Upper Cretaceous Gaogou Formation, Xiaguan-Gaoqiu Basin, Neixiang County, Henan Province, China was assigned to the oofamily "Crocodiloolithidae". After 11 years, another clutch of 15 eggs of the same type associated with Mosaiceratops azumai and from the same county was identified as turtle eggs (Testudoolithus), based on the needle-like crystals interpreted as aragonite from their eggshells. Our detailed study of the clutch of 15 eggs and six clutches of the same ootaxon using transmitted/polarized light microscope, followed by scanning electron microscope observations combined with electron backscatter diffraction analysis showed that their eggshells are dominated by secondary calcite; with a few pristine aragonite crystals that unequivocally support the turtle affinity of the eggs. Furthermore, superimposed cone-shaped structural units with radial ultrastructures, combined with the extremely thick eggshell challenges the assignment to the oogenus Testudoolithus. Hence, we suggest that this ootaxon could represent a new oogenus of Testudoolithidae. Although additional eggshell units were reported in the abnormal fossil turtle egg with multilayered eggshell from the Judith River Formation in Montana, U.S.A, the relatively constant eggshell thickness indicates that the eggs from Neixiang are not pathological. Therefore, this is the first report of superimposed structural units inside normal turtle eggshells, revealing the unique eggshell formation mechanism of the extinct turtle from Neixiang. Moreover, the aragonite discovered in the eggs may extend the temporal record of confirmed aragonite in turtle eggs. The crystallographic comparison between the eggs from Neixiang and the fossil turtle eggshells from Zhejiang Province and Montana revealed the transformation process from aragonite to calcite in fossil turtle eggshell.

Moganopterus zhuiana Lü et al.,2012 was erected as a member of the Boreopteridae,which was questioned by different researchers shortly after the publication.Although the new assignment to the Ctenochasmatidae is widely accepted by pterosaur researchers,some characteristics still require a detailed description.Here,the holotype of this taxon is restudied,and some ambiguous characteristics are re-identified.The diagnosis of this taxon has been revised as the following:a large ctenochasmatid pterosaur,which can be distinguished from other members of this clade by a single autapomorphy:an elongated rod-like parietal crest that extends posterodorsally,forming an angle of about 15° with the ventral margin of the skull.This taxon can be further distinguished from other ctenochasmatids on the basis of the following combination of characteristics:straight occlusal surfaces of the upper and low jaws;presence of a low premaxillary crest confined anterior to the nasoantorbital fenestra;rostrum about two thirds of the skull length;nasoantorbital fenestra occupying slightly more than 20％of the skull length;about 100 slender teeth;and a mid-cervical length/width ratio of about 7.The wingspan of M.zhuiana has been re-estimated according to a simple regression equation for wingspan versus skull length in ctenochasmatids.It confirms that M.zhuiana,although smaller than previous thought,is still the largest known ctenochasmatid.When comparing the sizes of ctenochasmatids in the Jurassic and Cretaceous,ctenochasmatids showed a rough tendency to increase their sizes.

Moganopterus zhuiana Lü et al. 2012 was erected as a member of the Boreopteridae, which was questioned by different researchers shortly after the publication. Although the new assignment to the Ctenochasmatidae is widely accepted by pterosaur researchers, some characteristics still require a detailed description. Here, the holotype of this taxon is restudied, and some ambiguous characteristics are re-identified. The diagnosis of this taxon has been revised as the following: a large ctenochasmatid pterosaur, which can be distinguished from other members of this clade by a single autapomorphy: an elongated rod-like parietal crest that extends posterodorsally, forming an angle of about 15° with the ventral margin of the skull. This taxon can be further distinguished from other ctenochasmatids on the basis of the following combination of characteristics: straight occlusal surfaces of the upper and low jaws; presence of a low premaxillary crest confined anterior to the nasoantorbital fenestra; rostrum about two thirds of the skull length; nasoantorbital fenestra occupying slightly more than 20% of the skull length; about 100 slender teeth; and a mid-cervical length/width ratio of about 7. The wingspan of M. zhuiana has been re-estimated according to a simple regression equation for wingspan versus skull length in ctenochasmatids. It confirms that M. zhuiana , although smaller than previous thought, is still the largest known ctenochasmatid. When comparing the sizes of ctenochasmatids in the Jurassic and Cretaceous, ctenochasmatids showed a rough tendency to increase their sizes.

Tooth replacement rate is an important feature related to feeding mechanics and food choices for dinosaurs. However, only a few data points are available for sauropod dinosaurs, partially due to rarity of relevant fossil material. Four somphospondylan sauropod species have been recovered from the Lower Cretaceous Aptian–Albian Haoling Formation in the Ruyang Basin, Henan Province of central China, but no cranial material has been reported except for a single crown. Here we report the discovery of the rostral portion of a left dentary with replacement teeth in its first five alveoli. Comparative anatomical study shows the partial dentary can be assigned to a member of early diverging somphospondylans. The non-destructive tooth length-based approach to estimating tooth formation time and replacement rate is adopted here. The estimated tooth replacement rate is 76 days, faster than that of Brachiosaurus (83 days) and much lower than typical late diverging lithostrotian titanosaurians (20 days). Thus, this discovery adds an intermediate tooth replacement rate in the evolution of titanosauriform sauropods and supports the idea that evolution of tooth replacement rate is clade-specific. This discovery also provides more information to understand the Ruyang sauropod assemblage, which includes one of the most giant dinosaurs to have walked our Earth (Ruyangosaurus giganteus).

A new enantiornithine bird is described on the basis of a well preserved partial skeleton from the Upper Cretaceous Qiupa Formation of Henan Province (central China). It provides new evidence about the osteology of Late Cretaceous enantiornithines, which are mainly known from isolated bones; in contrast, Early Cretaceous forms are often represented by complete skeletons. While the postcranial skeleton shows the usual distinctive characters of enantiornithines, the skull displays several features, including confluence of the antorbital fenestra and the orbit and loss of the postorbital, evolved convergently with modern birds. Although some enantiornithines retained primitive cranial morphologies into the latest Cretaceous Period, at least one lineage evolved cranial modifications that parallel those in modern birds.

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。

The trace elements and isotopic compositions of macroelongatoolithid eggshells provide insights into the palaeoenvironment of these huge eggs preservation. We analysed the geochemical characteristics of newly discovered macroelongatoolithid eggs from the early Cretaceous Zhaoying Formation in the Xixia Basin, Henan Province, China. X-ray diffraction results reveal that the minerals of these eggs are predominately composed of calcite. The major elements in eggshells are Ca, Mg, K, Na, Al, Fe and Ti, and trace elements mainly include Sr, Ba, Mn, La, As, Sc, V, Cr, Co, Ni, Cu, Pb, Zn, Cd, U, and Ir. The high Sr and Ir concentrations could be caused by food materials and drinking water of dinosaurs. delta C-13 values of eggshells varying between -7.19 parts per thousand and -5.08 parts per thousand (average -5.69 parts per thousand) indicate the C3 plants for dinosaurs with relatively high atmospheric CO2 concentration and low mean annual precipitation (MAP); further researches show that the carbon isotopic composition of atmospheric CO2 was around -4.11 parts per thousand to -2.19 parts per thousand, and the MAP was lower than 10 mm/yr. delta C-13 values varying between -5.72 parts per thousand and - 3.28 parts per thousand (average -4.53 parts per thousand) show the temperature of nesting area were about 23 degrees C and the drinking water was dominated by leaf water with few meteoric water. The palaeoenvironment in which these huge eggs were preserved could be interpreted as continental deposit with extremely arid climate in the early Late Cretaceous Xixia Basin based on the high Fe contents of eggshells, the low palaeoclimate index of surrounding rocks, and the extremely low MAP shown by oxygen isotope. (C) 2020 Elsevier Ltd. All rights reserved.

豫南南阳盆地西峡赵营村上白垩统高沟组含有较多的恐龙蛋化石,其中最为著名的是"路易贝贝"胚胎化石.对含化石地层中恐龙蛋的保存特征和古气候重建,可进一步认识白垩纪恐龙灭绝的古环境背景和原因.本文实测赵营村剖面厚约267.8 m,主要由下伏泥盆系南湾组(厚7.9 m)、上白垩统高沟组(厚259.9 m,未到顶)组成.通过地层沉积物结构构造观测和样品采集,在室内进行了元素、碳酸盐碳氧同位素组成、有机质饱和烃生标化合物等测试.结果表明,高沟组沉积物主要源于熊耳山岩浆岩的风化和短距离迁移,恐龙蛋化石主要保存于海拔200～800 m的山麓至平原过渡带的河漫滩环境,以原地埋藏为主.降雨量的变化造成河漫滩与河道频繁变化,从而导致恐龙在山麓与河漫滩之间来回迁栖.生物标志化合物分析表明,含恐龙蛋化石地层有机质主要来源于水生植物、菌藻类和陆生植物,但植被总体不发育.利用地层沉积岩Si/Al、CIA、Rb/Sr比值,以及 δ13C、δ18O等环境指标对高沟组古气候重建,该时期发生了较为快速的旋回变化,经历了暖干—暖湿—干旱—暖湿—干旱的古气候演变过程,总体上呈逐渐干旱化的趋势.通过赵营村晚白垩世早期恐龙蛋化石的埋藏、以及地层的古环境重建,说明古气候、古环境状况可能是影响恐龙生存的主要因素,大量恐龙蛋不能完全孵化以及气候的干旱化导致植被恶化可能是恐龙逐渐消亡的原因.

Anchiornis huxleyi, which is a member of the Middle–Late Jurassic Yanliao Biota, is the smallest feathered dinosaur ever known. It has been described as a critical link between feathered dinosaurs and birds. Recent studies, including those of Anchiornis, Xiaotingia, Eosinopteryx and Aurornis, challenged Archaeopteryx as the most basal bird. The new Anchiornis huxleyi specimens that are described in this paper show some minor different characters compared to previously reported Anchiornis specimens, which has revised the character list of Anchiornis and indicates a different phylogenetic point from former opinions.

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. Eggshell porosity indicates that the eggs of all oviraptorosaurs were exposed in the nest, similar to brooding birds. Although all oviraptorosaur clutches consist of radially arranged eggs in a ring configuration, clutch morphology varies in that the central opening is small or absent in the smallest species, becomes significantly larger in larger species, and occupies most of the nest area in giant species. Our results suggest that the smallest oviraptorosaurs probably sat directly on the eggs, whereas with increasing body size more weight was likely carried by the central opening, reducing or eliminating the load on the eggs and still potentially allowing for some contact during incubation in giant species. This adaptation, not seen in birds, appears to remove the body size constraints of incubation behaviour in giant oviraptorosaurs.

An alvarezsaurid dinosaur skeleton was discovered from the Late Cretaceous Qiupa Formation of Luanchuan, Henan Province of centtral 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.

以往关于窃蛋龙类“偷蛋”的“指责”已经被认为是一个冤案.但是,一直没有找到真正的凶手.最新研究表明,阿尔瓦兹龙类恐龙可能是真正的盗窃龙蛋者. 20世纪20年代,美国自然历史博物馆组织的中亚考察团在蒙古国西南戈壁的火山崖首次发现窃蛋龙类化石,亨利·奥斯本于1924年正式将其命名为食角龙蛋窃蛋龙.此后近半个多世纪,窃蛋龙一直背负着很不光彩的“盗贼”恶名.有一部分进步的窃蛋龙类牙齿退化缺失,且上颌中部具有假牙状突起,人们猜测这种假牙状突起是用来压碎恐龙蛋的,似乎找到了它们“作案”的把柄,然而并没有找到它们“偷蛋”的直接化石证据.事实上,迷你豫龙和南康龙等窃蛋龙类的肢骨比例特征及下颌特征显示:它们可能为植食性恐龙.

Small, gracile mostly tridactyl tracks from the Middle Jurassic of Henan Province represent the first example of the ichnogenus Anomoepus from this region. They represent a growing number of reports (at least eight) of this ichnogenus from the Jurassic of China. In conjunction with Changpeipus and Eubrontes, they appear characteristic of known global footprint biochrons. Anomoepus indicates the presence of ornithischian dinosaurs that are often scarce or unknown from skeletal remains in coeval deposits. When first discovered, these tracks were informally referred to as bird tracks. This interpretation reflects convergence between small Jurassic Anomoepus and avian theropod tracks that are hitherto known only from the Cretaceous and the Cenozoic. However, most Anomoepus are larger and more robust than any hitherto known Mesozoic avian tracks.

The abundance of dinosaur eggs in Upper Cretaceous strata of Henan Province, China led to the collection and export of countless such fossils. One of these specimens, recently repatriated to China, is a partial clutch of large dinosaur eggs ( Macroelongatoolithus ) with a closely associated small theropod skeleton. Here we identify the specimen as an embryo and eggs of a new, large caenagnathid oviraptorosaur, Beibeilong sinensis . This specimen is the first known association between skeletal remains and eggs of caenagnathids. Caenagnathids and oviraptorids share similarities in their eggs and clutches, although the eggs of Beibeilong are significantly larger than those of oviraptorids and indicate an adult body size comparable to a gigantic caenagnathid. An abundance of Macroelongatoolithus eggs reported from Asia and North America contrasts with the dearth of giant caenagnathid skeletal remains. Regardless, the large caenagnathid- Macroelongatoolithus association revealed here suggests these dinosaurs were relatively common during the early Late Cretaceous.

Four carcharodontosaurid teeth from the Cretaceous deposits of Ruyang County, Henan Province of central China are described in detail. The discovery of these large teeth indicates that some of the largest predatory dinosaurs coexisted with the gigantic plant-eating dinosaurs of this fauna, and these predators were likely the top consumers in the food chain. The teeth also further corroborate the biogeographic model by previous researchers that the carcharodontosaurids were broadly distributed rather than restricted to Gondwana, and this report expands the known non-Gondwanan record of the clade. Gigantic sauropod dinosaurs such as Ruyangosaurus and Huanghetitan ruyangensis were also found in the same area.

"Baby Louie" dinosaur fossil embryo, located at the bottom of Upper Cretaceous Gaogou Formation in Xixia Basin, was excavated from Zhaoying Village of Yangcheng Township in Xixia County of Nanyang City, Henan Province. Upper Cretaceous strata of Xixia Basin can be divided from bottom to top into Gaogou Formation, Majiacun Formation and Sigou Formation. "Baby Louie"is embryonic skeleton fossil of Macroelongatoolithus xixaensis. Gaogou Formation is rich in dinosaur egg fossils and little dino?saur bone fossils as well as a few fossil fragments of bivalve, gastropods, Ostracods, Charophyceae, plant pollen, and plant fossil togeth?er with abundant trace fossils. According to geological age of fossils in combination with conformable contact between Majiacun For?mation and Gaogou Formation as well as fossil assemblage of Sigou Formation, angular contact between Gaogou Formation and Low?er Devonian Nanwan Formation and stratigraphic correlation with surrounding basin layers, the authors hold that geological epoch of Gaogou Formation in Xixia Basin should be Late Cretaceous Coniacian. The lower and middle Gaogou Formation seems to be terrig? enous clastic rocks of semi-arid red continental type molasse-like formation belonging to alluvial fan and braided river sedimentation of intermittent muddy waters, whereas the upper part of Gaogou Formation seems to be alluvial fan and traction current deposit. The horizontal paleo-geographic environment of"Baby Louie"is flat and wide alluvial fan facing south at the alluvial end, which can be classified as alluvial fan facies-fan end subfacies-flowing microfacies.