Cretaceous Research最新文献_第5页

Agglutinated foraminifera and calcareous nannoplankton proxies for age determination and paleoenvironmental reconstruction of an Upper Cretaceous succession in the North Sudetic Cretaceous Basin (Germany) 德国北苏台德白垩世盆地上白垩世演替的凝集有孔虫和钙质纳米浮游生物代用物年龄测定和古环境重建

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-10-16 DOI: 10.1016/j.cretres.2025.106256

Richard M. Besen , Ramona Bălc , Mădălina-Elena Kallanxhi

The present study presents the findings of a comprehensive analysis of agglutinated foraminifera and calcareous nannoplankton from drill core Spremberg Cu Sp 101/6, situated within the North Sudetic Cretaceous Basin in Germany. These results provide refined biostratigraphic data and contribute to the paleoenvironmental reconstruction for both surface and bottom water conditions in the studied region.

Several calcareous nannoplankton taxa facilitated the identification of specific biozones, including Eiffellithus eximius (UC8), Micula staurophora (UC10), and Lithastrinus grillii (UC11). Notably, M. staurophora and L. grillii display significantly earlier occurrences when correlated with inoceramid zonation, indicating a diachronous first appearance of these taxa.

Using cluster analysis, principal component analysis, and taxonomical information, microfossil assemblages suggest that shallower, eutrophic conditions prevailed during the Cenomanian, whereas the Turonian was characterized by less diverse and poorly preserved assemblages. During the Coniacian, calcareous nannofossil assemblages indicate fluctuations between intervals of poor preservation and phases of increased assemblage diversity, probably associated with eutrophic conditions during the early Coniacian. This was followed by a transition to predominantly oligotrophic and deeper conditions during the middle to late Coniacian. Changes in the agglutinated foraminiferal assemblages likely reflect the grade of disturbance of bottom-water conditions mostly controlled by regional subsidence.

本文介绍了对德国北苏德海白垩纪盆地Spremberg Cu Sp 101/6钻孔岩心中凝集有孔虫和钙质纳米浮游生物的综合分析结果。这些结果提供了精细的生物地层资料，有助于研究区表层和底水条件的古环境重建。一些钙质纳米浮游生物分类有助于确定特定的生物带，包括Eiffellithus eximius （UC8）、Micula staurophora （UC10）和Lithastrinus grillii （UC11）。值得注意的是，M. staurophora和L. grillii的出现时间明显早于接种带，表明这两个分类群的首次出现具有历时性。利用聚类分析、主成分分析和分类信息，微化石组合表明，在塞诺曼期，较浅的富营养化条件占主导地位，而在Turonian，组合的多样性较少，保存较差。在Coniacian期间，钙质纳米化石组合表明在保存不良的间隔和组合多样性增加的阶段之间波动，可能与早期Coniacian的富营养化条件有关。随后在Coniacian中后期过渡到主要的少营养和更深的条件。凝集有孔虫组合的变化可能反映了主要受区域沉降控制的底水条件扰动程度。

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引用次数: 0

Diagenetic characterization of crocodyliform fossils from the Adamantina Formation (Upper Cretaceous, Bauru Group): Evaluating the chemical alteration of skeletal tissues through a multi-technique approach 上白垩统Bauru群Adamantina组鳄鱼形化石的成岩特征：通过多技术方法评估骨骼组织的化学变化

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-10-14 DOI: 10.1016/j.cretres.2025.106248

Fellipe P. Muniz , Annie Schmaltz Hsiou , Fabio Dias de Andrade , Gabriel Ladeira Osés , Márcia A. Rizzutto , Mírian Liza Alves Forancelli Pacheco

The Adamantina Formation hosts one of the most well-documented Late Cretaceous continental faunas in South America, with crocodyliforms standing out for their unusual richness and ecomorphological diversity. While their taxonomy and anatomy have been widely studied, the understanding of their fossilization processes has been largely overlooked. Here, we apply a multi-technique approach to analyze diagenetic alterations of the skeletal elements of crocodyliforms from the Adamantina Formation, combining information from energy dispersive X-ray fluorescence, scanning electron microscopy with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. Our results indicate significant structural and compositional changes, including loss of the organic matrix, void permineralization, ionic substitutions, and recrystallization. Although organic molecules were not unambiguously detected, some Raman spectra exhibited bands in the 1000–1800 cm⁻¹ range that resemble signals previously linked to organic compounds, but which may instead result from fluorescence induced by rare earth elements. Void-filling minerals reflect the prevailing influence of both alkaline (e.g., calcite, relict siderite) and oxidizing (iron oxyhydroxides) pore waters. All samples showed transformation of the original bioapatite into carbonated fluorapatite, highlighting the importance of the precipitation of a more thermodynamically stable phase for the long-term survival of skeletal remains. Raman spectroscopy further revealed differences in fossil apatite preservation among samples, with some showing less alteration and potentially storing original chemical information. The combination of techniques used in this study allowed a comprehensive assessment of the mode and degree of diagenetic alteration of crocodyliform remains, which might be useful when selecting samples for molecular or isotopic studies.

Adamantina组拥有南美洲记录最完整的晚白垩世大陆动物群之一，鳄鱼类以其不同寻常的丰富性和生态形态多样性而脱颖而出。虽然它们的分类学和解剖学已经被广泛研究，但对它们的石化过程的理解在很大程度上被忽视了。本文采用多技术方法，结合能量色散x射线荧光、扫描电镜与能量色散x射线能谱、微拉曼光谱和x射线衍射等信息，分析了Adamantina组鳄鱼形化石骨骼元素的成岩变化。我们的结果表明了显著的结构和组成变化，包括有机基质的损失，空隙过矿化，离子取代和再结晶。虽然有机分子没有被明确地检测到，但一些拉曼光谱在1000-1800 cm−1范围内显示出类似于以前与有机化合物相关的信号，但这可能是由稀土元素诱导的荧光引起的。填空矿物反映了碱性（如方解石、残余菱铁矿）和氧化性（氧化铁）孔隙水的普遍影响。所有样品都显示原始生物磷灰石转变为碳化氟磷灰石，强调了更热动力学稳定阶段的沉淀对骨骼遗骸长期存活的重要性。拉曼光谱进一步揭示了不同样品中化石磷灰石保存的差异，有些样品显示较少的蚀变，可能储存了原始的化学信息。本研究中使用的技术组合允许对鳄鱼形遗骸的成岩改变模式和程度进行全面评估，这可能在选择分子或同位素研究样本时有用。

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引用次数: 0

Paleoclimate variation during the Cretaceous revealed by geochemical and mineralogical analyses from continental sediments in northern Vietnam 越南北部大陆沉积物地球化学和矿物学分析揭示的白垩纪古气候变化

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-09-20 DOI: 10.1016/j.cretres.2025.106246

Pham Thi Nga , Taro Higuchi , Kentaro Oe , Nguyen Quoc Dinh , Rajat Mazumder , Tohru Ohta

Severe aridification has been recognized in low-latitude areas of Southeast Asia during the mid-Cretaceous; however, previous studies mainly focused on continental interior basins. Here, we investigate Cretaceous continental sediments from northern Vietnam, located in the Southeast Asian continental margin, where a precise study has not been conducted. The geochemical and mineralogical characteristics of mudstones collected from the Ban Hang and Yen Chau formations revealed fluctuations in climate conditions in northern Vietnam, including a slight humidification from the Early to mid-Cretaceous and aridification in the Late Cretaceous. Northern Vietnam is considered to have experienced a temperate semi-arid climate in the Early Cretaceous but shifted to a hot and sub-humid environment in the mid-Cretaceous and then returned to arid conditions in the late Period. The results indicate that the coastal area of Southeast Asia was more humid than the inland due to its proximity to the proto-Pacific Ocean. We also detected an increase in humidity in the coastal area during the mid-Cretaceous, contrasting with the inland regions where extreme aridification progressed. This contrasting paleoclimate regime was probably established by the isolation of coastal and inland areas by the tectonic re-configuration of the Southeast Asian continent. During the Cretaceous, closure of the Meso-Tethys Ocean and collisional tectonics generated a coastal mountain range, which caused the orogenic rain-shadow effects, i.e., increased precipitation in the coastal area and intensified desertification in the inland area. The present contribution indicates that the Cretaceous paleoclimate conditions in Southeast Asia were primarily constrained by the regional geographical background rather than the global climate system.

在白垩纪中期，东南亚低纬度地区发生了严重的干旱化；然而，以往的研究主要集中在大陆内部盆地。在这里，我们研究了位于东南亚大陆边缘的越南北部的白垩纪大陆沉积物，在那里没有进行过精确的研究。banhang组和Yen Chau组泥岩的地球化学和矿物学特征揭示了越南北部气候条件的波动，包括早白垩世至中白垩世的轻微湿润和晚白垩世的干旱化。越南北部被认为在白垩纪早期经历了温带半干旱气候，但在白垩纪中期转向炎热和半湿润的环境，然后在白垩纪晚期回到干旱条件。结果表明，东南亚沿海地区由于靠近原太平洋，湿润程度高于内陆地区。我们还发现，在白垩纪中期，沿海地区的湿度有所增加，与内陆地区的极端干旱化形成对比。这种对比鲜明的古气候体系可能是由于东南亚大陆的构造重构使沿海地区与内陆地区分离而形成的。在白垩纪，中特提斯洋的闭合和碰撞构造形成了沿海山脉，造成了造山雨影效应，即沿海地区降水增加，内陆地区沙漠化加剧。目前的研究表明，东南亚白垩纪古气候条件主要受区域地理背景的制约，而不是全球气候系统的制约。

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引用次数: 0

A new amber Lagerstätte from the Lower Cretaceous of Japan 日本下白垩纪发现的新琥珀Lagerstätte

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-09-15 DOI: 10.1016/j.cretres.2025.106236

Aya Kubota , Ryo Taniguchi , Yoshinori Hikida , Yasuhiro Iba

During the Early Cretaceous, terrestrial ecosystems underwent a critical transition driven by the emergence and diversification of angiosperms. Amber-rich deposits from this period are crucial for understanding the diversity, interactions, and evolution of terrestrial biota. However, their occurrences are limited both geographically and stratigraphically. Here, we report a new amber Lagerstätte from the upper Aptian (116–114 Ma) in northern Hokkaido, Japan. The abundant amber occurs within deep-sea deposits and is rich in bio-inclusions: arthropods (hymenopterans, mites), fungi, and plant remains (tracheids, stellate hairs, pollen grains), with submicron-scale morphological details. This is the first report of fossiliferous amber-rich deposits from the Aptian in Asia. It is also recognized as one of the older amber-rich localities with bio-inclusions following those in northeastern Italy (Carnian, Upper Triassic), the Levantine area (Tithonian, Upper Jurassic; Barremian), Austria (Hauterivian), the United Kingdom (lower Barremian), and southern Congo (upper Aptian). This finding fills a paleobiogeographical gap in fossil record and provides anatomical and ecological insights into a critical interval marked by the rise of modern-type forest ecosystems.

在白垩纪早期，被子植物的出现和多样化推动了陆地生态系统的关键转变。这一时期的富含琥珀的沉积物对了解陆地生物群的多样性、相互作用和进化至关重要。然而，它们的出现在地理和地层上都是有限的。本文报道了在日本北海道北部Aptian上（116-114 Ma）发现的一种新琥珀Lagerstätte。丰富的琥珀存在于深海沉积物中，富含生物包裹体：节肢动物（膜翅目动物、螨虫）、真菌和植物遗骸（管状体、星状毛、花粉粒），具有亚微米尺度的形态细节。这是亚洲阿普tian地区首次发现富含琥珀的化石矿床。它也被认为是继意大利东北部（卡尼期，上三叠世），地中海地区（梯东期，上侏罗纪，巴雷米期），奥地利（Hauterivian），英国（下巴雷米期）和刚果南部（上阿普tian）之后最古老的富含琥珀的地区之一。这一发现填补了化石记录中的古生物地理学空白，并为现代森林生态系统兴起的关键时期提供了解剖学和生态学的见解。

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引用次数: 0

Early Cretaceous freshwater bivalves from northeastern Brazil: Insights into the evolutionary history of South American freshwater mussels 巴西东北部早白垩世淡水双壳类：对南美淡水贻贝进化史的洞察

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-08-28 DOI: 10.1016/j.cretres.2025.106212

Victor R. Silva , Vitor B. Guerrini , Filipe G. Varejão , Rafael C. Silva , Katie Collins , Ismar S. Carvalho , Simon Schneider , Marcello G. Simões

We revise and describe the Early Cretaceous (Berriasian to Albian) freshwater bivalves from northeastern Brazil, including representatives of Unionida, Trigoniida, and potentially Sphaeriida. Three genera previously thought to be endemic to the Aptian to Albian Crato and Romualdo formations, Araripe Basin, Ceará State, i.e. Cratonaia, Araripenaia, and Monginellopsis, are now recorded from other interior basins. The Berriasian to Barremian Mont Serrat Conglomerate (Salvador Formation) of the Recôncavo Basin, Bahia State, hosts a diverse Unionida-dominated fauna, including Mycetopoda, Anodontites?, Cratonaia, and potentially also hyriids. Specimens tentatively assigned to the neomiodontid Musculiopsis also occur. This fauna has mixed Gondwanan and Laurasian affinities and likely thrived in ephemeral streams and/or floodplain lakes. Araripenaia is recorded from the Aptian Marizal Formation of the Tucano Basin. Supposed representatives of Sphaerium from the same strata are clam shrimps (Diplostraca). Cratonaia and Monginellopsis occur in the Aptian-Albian Itapecuru Formation of the Parnaíba Basin, Maranhão State. Articulated shells of Cratonaia, Araripenaia, and Monginellopsis are typically associated with fluvial-lacustrine deposits. Their common occurrence in Aptian-Albian strata of northeastern Brazil suggests dispersal via fluvial systems connecting the different sedimentary basins. These northeastern Brazilian assemblages are distinct from those of the Upper Cretaceous Bauru Basin in southeastern Brazil. Despite South America and North Africa being connected for most of the Early Cretaceous, no shared freshwater bivalves are known. The newly described faunas provide insight into South American Early Cretaceous freshwater mussel diversity when the proto-South Atlantic was dominated by alluvial and lacustrine settings hosting abundant but poorly known freshwater bivalves.

我们对巴西东北部早白垩世（Berriasian - Albian）淡水双壳类进行了修正和描述，包括Unionida、Trigoniida和Sphaeriida的代表。以前被认为是阿普tian到Albian克拉托和Romualdo组，Araripe盆地，cerar State特有的三个属，即Cratonaia， Araripenaia和Monginellopsis，现在从其他内陆盆地记录下来。巴伊亚州Recôncavo盆地的Berriasian - Barremian Mont Serrat砾岩（Salvador组）拥有多种以unionida为主的动物群，包括足类动物、Anodontites？克拉通那亚，也可能是混血儿。也出现了暂定为新齿纲肌肉纲的标本。这种动物混合了冈瓦纳和劳拉的亲缘关系，可能在短暂的溪流和/或洪泛区湖泊中繁衍生息。Araripenaia记录于Tucano盆地Aptian Marizal组。假定来自同一地层的球形目的代表是蛤虾（蛤虾属）。Cratonaia和Monginellopsis发生在马拉州Parnaíba盆地的Aptian-Albian Itapecuru组。克拉通、Araripenaia和Monginellopsis的铰接壳通常与河流-湖泊沉积有关。它们在巴西东北部Aptian-Albian地层中普遍存在，表明它们是通过连接不同沉积盆地的河流系统传播的。这些巴西东北部的组合与巴西东南部的上白垩纪Bauru盆地的组合不同。尽管在早白垩纪的大部分时间里，南美洲和北非是相连的，但没有已知的淡水双壳类动物。新描述的动物群提供了对南美早白垩世淡水贻贝多样性的深入了解，当时原南大西洋由冲积和湖泊环境主导，拥有丰富但鲜为人知的淡水双壳类。

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引用次数: 0

Stratigraphic sequence and age determination of the cretaceous rift-sag transition period in the Songliao basin, NE China: Based on new data from ICDP boreholes SK2 and SK3 松辽盆地白垩系断陷过渡期的层序及年龄测定——基于ICDP SK2和SK3井的新资料

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-10-22 DOI: 10.1016/j.cretres.2025.106257

Shuo Liu , Youfeng Gao , Renjie Liang , Pujun Wang , Haibo Liu

The Songliao Basin's tectonic evolution comprises three stages: the syn-rift stage, post-rift stage, and structural inversion stage. The Yingcheng Formation and the Denglouku Formation record the strata corresponding to the transitional period from the syn-rift stage to the post-rift stage. However, the stratigraphic boundary between these two formations and the sedimentation time of the Denglouku Formation remain controversial. This paper undertakes a zircon isotope chronology study on the tuff from the lower part of the Denglouku Formation, based on the continuous coring data from the International Continental Scientific Drilling Program (ICDP) boreholes SK2 and SK3 in the Songliao Basin. The LA-ICP-MS U–Pb age of the tuff at 2359.35 m depth in the lower part of the Denglouku Formation in borehole SK3 is determined to be 105.4 ± 0.6 Ma, constraining the initial sedimentation time of the Denglouku Formation, while an age of 103.4 ± 0.8 Ma from the tuff at 2970.65 m at the base of the Denglouku Formation in borehole SK2 marks the end of the first member's sedimentation. By integrating the existing chronostratigraphic data with basin-scale stratigraphic correlations from the Songliao Basin, this study re-evaluates the controversial sandy conglomerates within the fourth member of the Yingcheng Formation in the northern Songliao Basin, demonstrating their affinity to the first member of the Denglouku Formation.

松辽盆地的构造演化分为三个阶段：同裂谷期、裂谷后期和构造反转期。营城组和登娄库组记录了同裂谷期向后裂谷期过渡时期的地层。但是，这两组的地层界线和登楼库组的沉积时间仍有争议。利用国际大陆科学钻探计划（ICDP） SK2、SK3井连续取心资料，对松辽盆地登娄库组下部凝灰岩进行了锆石同位素年代学研究。SK3钻孔登娄库组下部2359.35 m处凝灰岩LA-ICP-MS U-Pb年龄为105.4±0.6 Ma，限定了登娄库组的初始沉积时间；SK2钻孔登娄库组底部2970.65 m处凝灰岩年龄为103.4±0.8 Ma，标志着登娄库组一段沉积结束。结合松辽盆地已有的年代地层资料和盆地尺度地层对比，对松辽盆地北部营城组四段有争议的砂质砾岩进行了重新评价，表明其与登娄库组一段具有亲缘关系。

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引用次数: 0

New findings of lower Aptian charophytes from the Southern High Plateaus (Eastern Meseta, Morocco): biostratigraphic and biogeographic significance 摩洛哥南部高原（东梅塞塔）下阿普提亚蕨的新发现：生物地层学和生物地理意义

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-11-07 DOI: 10.1016/j.cretres.2025.106262

Hamid Haddoumi , Jordi Pérez-Cano , Rachid Chennouf , Jemaa Amakrane , Sidi Mohamed Mamoun

Two stratigraphic sections of the Southern High Plateaus (Eastern Meseta, Morocco) were sampled for the charophyte study. Seven clavatoracean taxa are described and illustrated from the Dekar 1 and Dekar 2 formations, including Echinochara lazarii, Atopochara trivolvis var. trivolvis, Clavator grovesii var. jiuquanensis, Clavator grovesii var. corrugatus, Clavator harrisii var. harrisii, Clavator harrisii var. reyi, and Clavator harrisii var. zavialensis. This assemblage is assigned to the upper part of the Eurasian Clavator grovesii var. jiuquanensis biozone. The occurrence of intermediate populations of C. grovesii var. jiuquanensis and C. grovesii var. corrugatus associated with intermediate populations of C. harrisii var. harrisii, C. harrisii var. reyi, and C. harrisii var. zavialensis, restricts the association to the lower Aptian. These new findings suggest that this area could be important for understanding the evolution of charophytes during the early Aptian. Furthermore, the study provides significant insights into the paleobiogeographic distribution of Lower Cretaceous charophytes, reporting the first record of C. grovesii var. jiuquanensis (previously described only from Eurasia) and C. grovesii var. corrugatus (previously known from the Iberian Peninsula and the United States) in Africa, along with the first report of Echinochara lazarii in the Western Atlas Domain. Similar lower Aptian assemblages had previously been described only in the Algarve Basin (South Portugal), suggesting a strong paleogeographic connection between these areas.

对南部高原（东梅塞塔，摩洛哥）的两个地层剖面进行了蕨草研究。从Dekar 1组和Dekar 2组描述并说明了7个钉钳纲分类群，包括棘齿钉钳（Echinochara lazarii）、三角生钉钳（Atopochara trivolvis var. trivolvis）、酒泉钉钳（Clavator grovesii var. jiuquanensis）、瓦状钉钳（Clavator grovesii var. wargatus）、哈里斯钉钳（Clavator harrisii var. harrisii）、哈里斯钉钳（Clavator harrisii var. reyi）和哈里斯钉钳（Clavator harrisii var. reyi）。该组合属于酒泉生物带的上部。酒泉县和瓦楞县稻螟中间居群与哈里斯螟、雷伊螟和扎维阿尔螟中间居群的关联，限制了稻螟与阿普梯下游地区的关联。这些新发现表明，这一地区可能对了解早期阿普梯叶蕨的进化具有重要意义。此外，该研究还对下白垩世蕨类的古生物地理分布提供了重要的见解，报道了非洲首次记录的C. grovesii var. jiuquanensis（以前只在欧亚大陆发现）和C. grovesii var.瓦状蕨（以前在伊比利半岛和美国发现），以及在西部阿特拉斯域首次报道的棘齿蕨。类似的下阿普提亚组合以前只在阿尔加维盆地（葡萄牙南部）被描述过，这表明这些地区之间存在很强的古地理联系。

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引用次数: 0

First didactyl theropod track from the Lower Cretaceous Kitadani Formation, Tetori Group, Fukui, Japan 日本福井鸟居群下白垩世北达谷组第一双足兽脚亚目足迹

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-10-08 DOI: 10.1016/j.cretres.2025.106249

Yuta Tsukiji , Soki Hattori , Yoichi Azuma

A small theropod track was discovered in the Lower Cretaceous Kitadani Formation at the Kitadani Dinosaur Quarry in Fukui, Japan. Its distinctive didactyl morphology suggests that the trackmaker was a deinonychosaurian theropod. The track measures 8.0 cm in length and 4.7 cm in width, with a divarication angle of 20° between digits III and IV. These features are consistent with those of the ichnogenus Velociraptorichnus. The track exhibits a centrally positioned metatarsophalangeal pad impression along its longitudinal axis, a feature also observed in other ichnotaxa interpreted as having been made by arctometatarsalian theropods. Given that the arctometatarsalian condition is restricted to troodontids within Deinonychosauria, the trackmaker is inferred to be a troodontid. This specimen represents the first record of a deinonychosaurian track from Japan and provides new ichnological evidence for the presence of deinonychosaurian theropods in the Kitadani Formation. Furthermore, it reinforces the previous hypotheses suggesting a close relationship between the dinosaur ichnofauna of the Kitadani Formation and other dinosaur ichnofaunas of the Lower Cretaceous in East Asia.

在日本福井的北达尼恐龙采石场的下白垩世北达尼组发现了一个小兽脚亚目恐龙的足迹。它独特的双足动物形态表明，这个脚印制造者是一种恐爪龙兽脚亚目恐龙。径迹长8.0 cm，宽4.7 cm，趾III和趾IV之间的分岔角为20°。这些特征与Velociraptorichnus属一致。足迹沿其纵轴显示了一个位于中心位置的跖趾垫印，这一特征也在其他石类群中观察到，被解释为是由掌跖目兽脚亚目动物留下的。考虑到手跖骨的情况仅限于恐爪龙中的齿形类，可以推断脚印制造者是一种齿形类。该标本是日本首次发现的恐爪龙足迹，为北达谷组存在恐爪龙兽脚亚目恐龙提供了新的技术证据。进一步证实了北达尼组恐龙区系与东亚地区其他下白垩统恐龙区系关系密切的假说。

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引用次数: 0

Diversity of araucariacean pollen from the Lower Cretaceous Rio da Batateira and lower Crato formations (Araripe basin, SE Brazil), based on micromorphology of the ektexine using SEM 巴西东南部Araripe盆地下白垩统里约热内卢da Batateira和下Crato组araucariacaceae花粉的SEM显微形态分析

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-10-28 DOI: 10.1016/j.cretres.2025.106260

Christa-Ch Hofmann , Mario Coiro , Ulrich Heimhofer , Emily A. Roberts , Leyla J. Seyfullah

Here we demonstrate the micromorphological variety of Aptian pollen grains affiliated with Araucariaceae s.l. with LM and SEM. We could distinguish five micromorphological groups and in addition to well known araucariacean pollen taxa such as Araucariacites spp., Balmeiopsis and Callialasporites spp., we could also assign Exesipollenites scabratus, E. cf. tumulus, and one Inaperturopollenites taxon as araucariacean. Using LM, a hidden diversity of micromorphological features are missed within the four pollen taxa (“Araucariaceae” sp. 1 to sp. 4) that are similar to the morphogenus Araucariacites demonstrating the importance of using scanning electron microscopy in palaeopalynology. Pollen characterized by micromorphological features of group 4 comprises Callialasporites spp., Inaperturopollenites sp. and “Araucariaceae” sp. 1 and are assumed to be dispersed equivalents of previously described eurypalynous pollen cones. These pollen cones and pollen grains might represent an ancient group of Araucariaceae with overlapping characters from Podocarpaceae and Araucariaceae. In total 15 Araucariaceae pollen taxa are present in the Rio da Batateira and lower Crato formations, a number that exceeds the diversity of previously described araucariacean macrofossils and pollen of the Araripe basin. These results are evidence that despite the rapid evolution of angiosperms in the Early Cretaceous, gymnosperms, particularly Araucariaceae, still played an important role in various ancient vegetation habitats.

本文利用光谱学和扫描电镜研究了阿普天科阿普天科花粉粒的显微形态变化。除了Araucariacites spp.、Balmeiopsis和Callialasporites spp.等已知的Araucariacites花粉类群外，还可以将Exesipollenites scabratus、E. cf. tumulus和一个Inaperturopollenites分类群划归为Araucariacites。利用扫描电镜技术，在与Araucariacites形态属相似的4个花粉分类群（“Araucariaceae”sp. 1至sp. 4）中遗漏了隐藏的微形态特征多样性，这表明了扫描电镜技术在古孢粉学中的重要性。以微形态特征为特征的第4组花粉包括Callialasporites spp., Inaperturopollenites sp.和Araucariaceae sp. 1，它们被认为是先前描述的泛孢花粉球果的分散等量物。这些花粉球果和花粉粒可能代表了一个古老的类群，它们具有木足科和木足科的重叠特征。在里约热内卢da Batateira和下克拉托地层中，共有15个araucariacaceae花粉分类群，其数量超过了先前描述的Araripe盆地araucariacaceae大化石和花粉的多样性。这些结果表明，尽管被子植物在早白垩世迅速进化，裸子植物，特别是砂桃科，仍然在各种古代植被栖息地中发挥着重要作用。

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引用次数: 0

Revisiting the taxonomic status of three Araripeneurinae (Neuroptera, Myrmeleontidae) genera from the lower Cretaceous Crato formation using geometric morphometrics as a complementary tool 利用几何形态计量学作为补充工具，重新考察了下白垩世克拉托组三个Araripeneurinae （Neuroptera, Myrmeleontidae）属的分类地位

IF 1.7 3区地球科学 Q1 GEOLOGY

Cretaceous Research

Pub Date : 2026-02-01 Epub Date: 2025-09-20 DOI: 10.1016/j.cretres.2025.106245

Gabriel M. Bueno , Renato J.P. Machado , Diego Almeida-Silva , Guilherme C. Ribeiro

The Crato Formation (Lower Cretaceous, Brazil) preserves a highly diverse fossil insect fauna, including 10 genera of Araripeneurinae (Neuroptera: Myrmeleontidae), whose taxonomy has long been hampered by limited access to type specimens and ambiguous original descriptions. Here, we revisit the taxonomic status of three genera—Cratopteryx Martins-Neto & Vulcano, Caririneura Martins-Neto & Vulcano, and Paracaririneura Martins-Neto & Vulcano—by integrating traditional morphological examination and redescriptions of holotypes with geometric morphometric analysis of forewing shape. Our results provide updated and objective diagnoses for these genera, clarify their distinctiveness based on robust morphometric separation in morphospace, and support the designation of a neotype for Cratopteryx nemopteroides Martins-Neto. We demonstrate the utility of geometric morphometrics as a complementary tool for fossil insect taxonomy, providing support for the validity of the studied genera. This revision, by restoring access and providing redescriptions of previously inaccessible holotypes, restores taxonomic stability and lays a foundation for future systematic and evolutionary studies on fossil Myrmeleontidae from the Crato Formation.

Crato组（巴西下白垩纪）保存了高度多样化的昆虫化石区系，包括Araripeneurinae（神经翅目：Myrmeleontidae） 10属，其分类长期受到模式标本有限和原始描述模糊的阻碍。本文通过结合传统形态学检查和对全型的重新描述以及翼前形状的几何形态测量分析，重新审视了三个属（cratopteryx martns - neto &; Vulcano, Caririneura martns - neto &; Vulcano）和Paracaririneura martns - neto &； Vulcano)的分类地位。我们的研究结果为这些属提供了更新和客观的诊断，在形态空间中明确了它们的独特性，并支持了nemopteroides martas - neto的新种命名。我们展示了几何形态计量学作为化石昆虫分类的补充工具的效用，为所研究属的有效性提供了支持。这一修订通过恢复和重新描述以前难以获得的全型，恢复了分类稳定性，并为今后对克拉托组Myrmeleontidae化石的系统和进化研究奠定了基础。

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引用次数: 0