Palaeoworld最新文献

Early Paleogene plant biomes of the Pacific side of Eurasia 古近纪早期欧亚大陆太平洋一侧的植物生物群落

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.06.007

Olesia V. Bondarenko , Torsten Utescher

Major plant biome changes in East Asia during the early Paleogene are studied using the Integrated Plant Record vegetation analysis for the first time based on paleobotanical records. The paleobotanical record employed for the reconstruction comprises 110 paleofloras covering the early Paleocene to early Eocene, a time-span of ca. 17 Myr. Our data indicate the presence of more forested conditions over East Asia during the early Paleogene than at present. The early Paleogene vegetation cover in the study area fundamentally differed from modern and was much more homogeneous compared to the modern one. Mixed mesophytic zonal vegetation dominated on the Pacific side of Eurasia during the early Paleogene. Thermophilous mixed mesophytic forests were distributed even at very high latitudes, but at the same time, ecotone between the mixed mesophytic / broadleaved evergreen forests and broadleaved evergreen forest were confined to regions south of 50°N. The proportions of sclerophyllous plants are low in general, even in the mid-latitudes. The localities with open woodlands are all located south of ca. 45°N. The observed vegetation patterns and their changes throughout the early Paleogene in many cases can be correlated with climate patterns and the overall continental paleoclimate evolution as reconstructed from the paleobotanical record. The higher-than-present spatial homogeneity of early Paleogene vegetation coincides with shallow temperature gradients and a significantly more humid regional rainfall pattern over East Asia during the early Paleogene.

利用基于古植物记录的 "综合植物记录植被分析"（Integrated Plant Record vegetation analysis），首次研究了古新世早期东亚主要植物生物群落的变化。用于重建的古植物记录包括 110 个古植物群落，涵盖早古新世至早始新世，时间跨度约 17 年。我们的数据表明，早古新世时期东亚地区的森林覆盖率高于现在。研究区域的早古新世植被覆盖与现代植被覆盖有着本质区别，与现代植被覆盖相比，早古新世植被覆盖更为均匀。在古近纪早期，欧亚大陆太平洋一侧的混合中生地带性植被占主导地位。嗜热中生混交林甚至在高纬度地区也有分布，但同时，中生混交林/常绿阔叶林和常绿阔叶林之间的生态区仅限于北纬50°以南地区。硬叶植物的比例普遍较低，即使在中纬度地区也是如此。有开阔林地的地方都位于北纬 45 度以南。观测到的植被模式及其在整个古新世早期的变化在很多情况下都与气候模式以及从古植物记录中重建的整个大陆古气候演变相关联。古新世早期植被在空间上的同质性高于现在，这与古新世早期东亚地区较浅的温度梯度和明显湿润的区域降雨模式相吻合。

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引用次数: 0

Palaeoenvironmental implications of a turritelline-dominated assemblage from Upper Cretaceous carbonate rocks of Narmada Basin, India 印度纳尔马达盆地上白垩统碳酸盐岩中以绿松石为主的集合体对古环境的影响

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.06.003

Prantik Mondal , Arunaditya Das , Biplab Bhattacharya , Kalyan Halder

Turritelline-dominated assemblages (TDAs) occur in modern siliciclastic seas within shallow depths, under normal to below normal salinity, high nutrient flux, high ocean upwelling current and/or runoff and cool water conditions. Similar assemblages in carbonate sediments are rare in modern oceans. However, TDA in carbonate rocks are common during the Cretaceous. In this study, we report the presence of a TDA in the late Turonian Nodular Limestone Formation of the Bagh Group, Narmada Basin, central India. An unusually small species of Turritella, T. bardhani Halder, n. sp., is described from the TDA. The TDA, in terms of host rock microfacies and taphonomy, indicates shallow water to intertidal, low to moderate energy, eutrophic to mesotrophic conditions, that prevailed in restricted lagoonal to marginal lagoonal, back-reef environments. The turritellines, based on trace elements and Rare Earth Elements concentration, thrived under dysoxic conditions and experienced above-normal marine salinities. The preferences of modern TDAs do not fully represent such past ecological and lithological conditions, indicating an example of a non-uniformitarian shift in habitat.

在正常或低于正常盐度、高营养通量、高海洋上升流和/或径流以及低温水条件下，在浅海的现代硅质岩海洋中出现了以涡虫为主的集合体（TDAs）。碳酸盐沉积物中的类似组合在现代海洋中很少见。然而，白垩纪碳酸盐岩中的 TDA 却很常见。在这项研究中，我们报告了印度中部纳尔马达盆地巴格组晚期都龙纪结核石灰岩层中出现的 TDA。这是一种异常小的Ⅳ级物种。Halder，n. sp.，描述了该TDA。从宿主岩的微构造和岩石学角度来看，TDA 表明浅水至潮间带、低至中等能量、富营养化至中营养化的条件，普遍存在于有限的泻湖至边缘泻湖、后礁环境中。根据痕量元素和稀土元素的浓度，涡虫类在缺氧条件下生长旺盛，海洋盐度高于正常水平。现代 TDAs 的喜好并不完全代表过去的生态和岩性条件，这表明栖息地发生了非均匀性转变。

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引用次数: 0

Taxonomy and evolutionary implications of a new fossil stonefly family (Insecta, Plecoptera) from Middle Cretaceous Kachin amber of northern Myanmar 缅甸北部中白垩世克钦邦琥珀中一个新的石蝇科化石（昆虫纲，褶翅目）的分类和进化意义

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.06.002

Zhi-Teng Chen

Plecoptera, commonly known as stoneflies, represent an ancient order of aquatic insects with significant ecological importance in freshwater ecosystems. This study describes a new genus and species of stonefly, Crossoperla teslenkoae n. gen. n. sp., based on a female adult preserved in Middle Cretaceous Kachin amber. Morphological examination reveals the taxonomic placement of C. teslenkoae within the infraorder Systellognatha of the suborder Arctoperlaria. Distinctive wing venation patterns and genitalic structures differentiate C. teslenkoae from extant and extinct stonefly families. A new extinct fossil family, Crossoperlidae n. fam. is established for the new stonefly. The findings contribute to the understanding of stonefly evolution, palaeodiversity, and ecological adaptations.

褶翅目，俗称石蝇，是一种古老的水生昆虫，在淡水生态系统中具有重要的生态意义。本研究描述了石蝇的一个新属和新种 n. gen. n. sp.形态学检查揭示了......在分类学上属于石蝇亚目石蝇科（Arctoperlaria）的下目（Systellognatha）。独特的翅脉模式和生殖器结构将.与现存和已灭绝的石蝇科区分开来。为新石蝇建立了一个新的已灭绝化石科--Crossoperlidae n. fam.。这些发现有助于了解石蝇的进化、古多样性和生态适应性。

引用次数: 0

New fossil woods from the middle Eocene climate optimum of north-central Turkey 土耳其中北部中始新世最佳气候的新木材化石

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.06.005

Ünal Akkemik , Özlem Toprak , Dimitra Mantzouka

The middle Eocene climate optimum, a crucial greenhouse event in Earth’s life history, occurred approximately 40 Ma. Fossil wood identifications of middle Eocene age reveal important evidence for the terrestrial tropical/subtropical conditions during this period. The purpose of the present study is to identify new fossil woods from the middle Eocene of north-central Turkey and to evaluate the paleoclimate and paleovegetational history of the north-central Turkey based on new records. Seven fossil woods were collected from the middle Eocene Göynücek Volcanics of the Çekerek Formation (Sarıkaya village, close to Çekerek, Yozgat). Two new species Apocynoxylon umuttuncii Akkemik and Mantzouka, n. sp., and Ficoxylon anatolicum Akkemik and Mantzouka, n. sp., are described, together with two more coniferous species Pinuxylon cf. P. tarnocziense (Tuzśon, 1901) Greguss, 1954 and Juniperoxylon cf. J. acarcaea Akkemik, 2021a. Although dealing with a rather low number of fossil wood findings, indistinct boundaries of the tree rings, low xeromorphy ratios and high conductivity values in these two new fossil angiosperm species and less visible and indistinct boundaries in the two fossil coniferous species may reflect the warm, humid tropical conditions of the middle Eocene of north-central Turkey. The results are consistent with our former paleoecological evaluation based on the fossil woods including Actinodaphnoxylon zileensis Akkemik and Mantzouka in Akkemik et al., 2021 from the same geological unit and Palmoxylon sabaloides Greguss, 1969 from the same area.

中始新世最佳气候期是地球生命史上一个关键的温室事件，大约发生在 40 Ma。中始新世的木化石鉴定揭示了这一时期陆地热带/亚热带条件的重要证据。本研究的目的是鉴定土耳其中北部中始新世的新木材化石，并根据新记录评估土耳其中北部的古气候和古植被历史。研究人员从切凯雷克地层的中始新世戈伊努切克火山岩（位于约兹加特省切凯雷克附近的萨勒卡亚村）中采集了七种木化石。描述了两个新种 Akkemik 和 Mantzouka，n. sp.，以及 Akkemik 和 Mantzouka，n. sp.，还有两个针叶树种 cf. （）和 cf. （）。虽然发现的木化石数量较少，但这两个新的被子植物化石物种的树木年轮边界不清晰、异形比低和电导率值高，以及两个针叶树化石物种的边界不明显和不清晰，可能反映了土耳其中北部始新世中期温暖潮湿的热带条件。这些结果与我们之前根据同一地质单元和同一地区的化石树林（包括 Akkemik 和 Mantzouka）进行的古生态评估结果一致。

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引用次数: 0

Shallow-water whale-fall communities: Evidence from the middle–late Eocene basilosaurid whale bones, Wadi El-Hitan, Fayum, Egypt 浅水鲸落群落：来自埃及法尤姆 Wadi El-Hitan 中新世晚期玄武鲸骨的证据

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.06.006

Esraa S. Ibrahim , Magdy M. El Hedeny , Ahmed M. El-Sabbagh , Gebely A. Abu El-Kheir , Alaa G. Osman , Aldoushy Mahdy , Enas A. Ahmed

The present study examines the basilosaurid whale bone specimens collected from the Sandouk El-Borneta section, Wadi El-Hitan (Valley of Whales), Fayum, Egypt. These specimens are embedded in highly fossiliferous calcareous sandstones of the middle Eocene Gehannam and the upper Eocene Birket Qarun formations. These whale bones display some post-mortem alterations, representing good signs of at least three distinct stages in what is called the whale fall. The co-occurrence of shark, ray, and crocodile fossil specimens with the examined whale bones may indicate the first mobile-scavenger stage. Borings of the siboglinid polychaete genus Osedax represent the most common worm type that deeply bioeroded the whale bones, contributing to their rapid degradation, and representing the enrichment-opportunist stage. These fossil traces of the bone-eating worm Osedax represent the first record in the Eocene Epoch regionally and inter-regionally, filling the gap between the Late Cretaceous and the Oligocene occurrences. Subsequently, the studied whale bones served as hard substrates for some calcareous tube-dwelling encrusting polychaetes, balanoid barnacles, sheet‐like cheilostome bryozoans, and scleractinian corals. Furthermore, a bioerosion structure produced by polychaete annelids was also observed. The presence of these sclerobionts assemblage confirms the well-developed final reef stage with prolonged exposure and colonisation of these whale bones prior to final burial. Based on the recorded post-mortem alterations, together with other sedimentological and palaeontological data, the studied whale bones were deposited in a shallow open marine bay to sheltered gulf environments, which were characterised by low depositional energy, low to moderate rate of sedimentation, and high surface water productivity.

本研究考察了从埃及法尤姆Wadi El-Hitan（鲸鱼谷）Sandouk El-Borneta地段采集的基龙类鲸骨标本。这些标本镶嵌在中始新世 Gehannam 和上始新世 Birket Qarun 地层的高化石钙质砂岩中。这些鲸骨显示了一些死后的变化，是鲸鱼陨落过程中至少三个不同阶段的良好迹象。鲨鱼、鳐鱼和鳄鱼化石标本与经检验的鲸骨同时出现，这可能表明第一阶段为移动清道夫阶段。鞘翅目多毛类的钻孔代表了最常见的蠕虫类型，它们对鲸骨进行了深度生物侵蚀，导致鲸骨迅速退化，代表了富集-机会主义阶段。这些食骨蠕虫化石痕迹是始新世区域内和区域间的首次记录，填补了晚白垩世和渐新世之间的空白。随后，所研究的鲸骨成为一些钙质管栖包壳多毛类、巴兰藤壶、片状螯足类和硬骨珊瑚的硬基质。此外，还观察到由多毛环毛虫产生的生物侵蚀结构。这些硬骨生物群的存在证实了这些鲸骨在最终埋葬前经过长期暴露和定殖，最终形成了发达的珊瑚礁阶段。根据所记录的死后变化以及其他沉积学和古生物学数据，所研究的鲸骨沉积在浅海开放海湾至遮蔽海湾环境中，这种环境的特点是沉积能量低、沉积速率低至中等、表层水生产力高。

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引用次数: 0

New data and redescription of Kellnerius jamacaruensis Santana et al., 2013, a Palaemonidae shrimp from the Araripe Basin in northeastern Brazil 来自巴西东北部 Araripe 盆地的虾科虾 Kellnerius jamacaruensis Santana et al.

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.05.005

Olga Alcântara Barros , Paulo Victor de Oliveira , Antônio Álamo Feitosa Saraiva

The preservation of shrimp in the fossil record is difficult due to their rapid decomposition. In this study, we provide new taxonomic insights into Kellnerius jamacaruensis from the Lower Cretaceous Romualdo Formation in the Araripe Basin, northeastern Brazil. A comprehensive taxonomic review, including a more meticulous preparation of the holotype and additional fossil material, enabled the disclosure of previously unknown anatomical features, reaffirming its classification within the family Palaemonidae.

由于虾类的快速分解，很难将其保存在化石记录中。在这项研究中，我们对巴西东北部 Araripe 盆地下白垩世 Romualdo 地层的虾类分类学有了新的认识。我们对其进行了全面的分类审查，包括对主模式和其他化石材料进行了更细致的制备，从而揭示了以前未知的解剖学特征，再次确认了其在帕拉伊蒙科中的分类。

引用次数: 0

The Early to Late Cretaceous (Albian–Cenomanian) transition in Putumayo, Colombia: A biostratigraphic and carbon isotope stratigraphic correlation for northwestern South America 哥伦比亚普图马约早白垩世向晚白垩世（阿尔卑斯-塞诺曼）的过渡：南美洲西北部的生物地层和碳同位素地层相关性

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.05.011

Javier Luque , Jonatan Bustos , Manuel Páez-Reyes , Alejandro Beltrán-Triviño , Angie Rodríguez , Alexandra Delgado , Johan M. Sánchez , Julián Caraballo , Mikel A. López-Horgue

Despite the rich geological and paleontological record of Colombia, the Putumayo region near Ecuador remains one of the least explored regions in the equatorial Neotropics, mainly due to its thick vegetation, deep rock weathering, soil formation and ground cover, geographic remoteness, and inaccessibility of well-exposed outcrops. This has resulted in limited comparisons with neighboring basins and thus the generation of more comprehensive biostratigraphic correlations with western and northern South America, as well as other paleobiogeographic regions (e.g., Tethys, Western Interior Seaway). Here, we present 67 occurrences of uppermost Lower Cretaceous to lowermost Upper Cretaceous ammonoids and other macrofossils (e.g., bivalves, decapod crustaceans, osteichthyan fish remains, plant remains), as well as a δ¹³C_org chemostratigraphic curve derived from 105 samples from the middle Albian of the uppermost Caballos Formation and the upper Albian to lower Cenomanian lower Villeta Formation, collected in situ from a stratigraphic section exposed along the Mocoa–San Francisco Road, Putumayo, Colombia, here called the San Francisco section. The chemostratigraphic, carbon-isotope curve for the region shows a great similarity with the shape of the accepted curve for the late Albian Oceanic Anoxic Event 1d, which is characterized by a worldwide long positive δ¹³C excursion anomaly. The new biostratigraphic and isotopic data serve as a point of reference to compare the Putumayo Basin with neighboring basins (e.g., Marañon Basin in Perú, Oriente Basin in Ecuador, Upper Magdalena Valley Basin in Colombia), and thus the generation of more comprehensive upper Lower Cretaceous and lower Upper Cretaceous biostratigraphic and chemostratigraphic correlations for northwestern South America.

尽管哥伦比亚拥有丰富的地质和古生物记录，但靠近厄瓜多尔的普图马约地区仍然是赤道新热带地区探索最少的地区之一，这主要是由于该地区植被茂密、岩石风化程度深、土壤形成和地面覆盖、地理位置偏远以及无法获得暴露良好的露头。这导致与邻近盆地的比较有限，因而无法与南美洲西部和北部以及其他古生物地理区域（如特提斯山脉、西内陆海道）建立更全面的生物地层关联。在此，我们介绍了 67 个地点出现的下白垩世最上至上白垩世最下层的氨类动物和其他大型化石（如双壳类动物、十足类甲壳）、这些样本采集自哥伦比亚普图马约省莫科阿-圣弗朗西斯科公路沿线出露的一个地层剖面，这里称为圣弗朗西斯科剖面。该地区的化学地层碳同位素曲线与公认的晚白垩世大洋缺氧事件 1d 的曲线形状非常相似，后者的特点是全球范围内出现了长δC 正偏移异常。新的生物地层学和同位素数据可作为普图马约盆地与邻近盆地（如秘鲁马拉尼翁盆地、厄瓜多尔奥连特盆地、哥伦比亚上马格达莱纳河谷盆地）进行比较的参照点，从而为南美洲西北部建立更全面的上白垩世和下白垩世生物地层学和化学地层学关联。

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引用次数: 0

Quantitative insights into osteocyte density developmental patterns in fossilized bone — A new method 对化石骨中骨细胞密度发育模式的定量研究--一种新方法

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.05.010

Denis Horvath , Xu-Ri Wang , Martin Kundrát

This study presents a new methodology that combines quantitative image analysis, clustering, and statistical techniques to examine the 2D distribution of osteohistological features in an extinct stem-group bird. The driving force of our research was the need to map ontogenetic changes in the spatial density of osteocyte lacunae in the type specimen of Musivavis amabilis from the Lower Cretaceous of China. We particularly focused on developing tools to reveal quantitative aspects of the dynamics in the formation of avascular bone in this active flier. We achieve this goal by proposing an algorithm with the following methodological steps: 1) We obtain relevant coordinate details for pixel locations selected by thresholding the original image with shading as a criterion. 2) We estimate density using the Gaussian kernel estimator and refined it through observations and regression analysis. 3) After slicing the image, we apply k-means clustering to obtain one-dimensional representations of lacunar density. 4) We proceed by implementing weighted averaging employing the k-nearest neighbor approach. Having applied these steps, we are able to quantitatively disclose growth processes previously unnoticed and reveal dynamics in the formation of lacunar bone tissue in the enantiornithine birds capable of power flight.

本研究提出了一种结合定量图像分析、聚类和统计技术的新方法，以研究一种已灭绝的茎类鸟类骨组织特征的二维分布。我们研究的动力是需要绘制中国下白垩统鸟类骨细胞裂隙空间密度的本体变化图。我们特别注重开发工具，以定量揭示这种活跃的飞禽无血管骨骼形成的动态变化。为实现这一目标，我们提出了一种包含以下方法步骤的算法：1) 我们以阴影为标准，对原始图像进行阈值化处理，从而获得像素位置的相关坐标细节。2) 我们使用高斯核估计器估计密度，并通过观察和回归分析对其进行改进。3) 对图像进行切片后，我们采用 K 均值聚类，以获得裂隙密度的一维表示。4) 接下来，我们采用 k 近邻法进行加权平均。应用这些步骤后，我们能够定量地揭示以前未曾注意到的生长过程，并揭示能够进行动力飞行的反鸟类的裂隙骨组织的形成动态。

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引用次数: 0

The disappearance of European dirk-toothed cats 欧洲岩齿猫的消失

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.05.003

Clàudia Tura-Poch , Saverio Bartolini-Lucenti , Qi-Gao Jiangzuo , Maria Prat-Vericat , Bienvenido Martínez-Navarro , Lorenzo Rook , Joan Madurell-Malapeira

Saber-toothed cats dominated the latest Pliocene to Early Pleistocene ecosystems in the Old World, potentially competing with early hominins for food resources. However, the Pleistocene fossil records of the medium-sized Megantereon are often fragmented and scarce, leading to contentious debates regarding its evolutionary history.

Previously, it was commonly believed that Megantereon became locally extinct in Europe during the Early Pleistocene, albeit without a precise timeline. In this study, we present findings from an unpublished Megantereon neurocranium discovered in the Iberian Vallparadís Section. This discovery is correlated with the Jaramillo magnetostratigraphic subchron (ca. 1.0 Ma; MIS30). Additionally, we propose a connection between the disappearance of European Megantereon and the climatic shifts associated with the ‘Early-Middle Pleistocene Transition’, particularly the increase in aridity and expansion of open landscapes observed during the protracted glacial stage MIS30.

剑齿虎主宰着旧大陆上新世晚期到更新世早期的生态系统，有可能与早期类人猿争夺食物资源。然而，中型剑齿虎在更新世的化石记录往往支离破碎，数量稀少，导致人们对其进化史争论不休。

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引用次数: 0

New record of Brachyoxylon wood from the Lower Cretaceous of Qingyuan, southeastern China and its palaeoclimatic implications 中国东南部清远下白垩统 Brachyoxylon 木的新记录及其古气候影响

IF 1.7 3区地球科学 Q2 PALEONTOLOGY

Palaeoworld

Pub Date : 2025-02-01 DOI: 10.1016/j.palwor.2024.05.004

Jian-Guo Hui , Su-Xin Yin , Xiao-Liang Cai , Chong Dong , Yuan-Dong Liu , Ning Tian , Gong-Le Shi

Early Cretaceous was a key period for the evolution of terrestrial ecosystems. In southeastern China, the late Early Cretaceous (Aptian–Albian) floras are relatively well known and characterized by diverse Cheirolepidiaceae, but the early Early Cretaceous floras in southeastern China are poorly known mainly because of the lack of plant fossils. Here we report petrified woods from a new early Early Cretaceous locality in Qingyuan, southern Zhejiang Province, southeastern China. The new fossil woods collected from the Xishantou Formation (earliest Berriasian, earliest Early Cretaceous) are assigned to Brachyoxylon zhejiangense Tian, Zhu, and Wang based on the anatomy of the secondary xylem. The new material of Brachyoxylon zhejiangense from Qingyuan lacks distinct growth rings or resin canals and has mixed type pitting on the radial walls of the tracheids, araucarioid cross-field pitting, and uniseriate rays. It is the earliest record of Brachyoxylon in southeastern China. Brachyoxylon zhejiangense has been regarded as the wood of the extinct conifer family Cheirolepidiceae and grew in arid to semi-arid environments. Evidence also suggests Cheirolepidiaceae played an important role in the vegetation of southeastern China throughout the Early Cretaceous.

早白垩世是陆地生态系统演化的关键时期。在中国东南部，早白垩世晚期（安息-阿尔卑斯）的植物区系比较著名，其特征是多种多样的箭竹科植物，但中国东南部早白垩世早期的植物区系却鲜为人知，主要原因是缺乏植物化石。在此，我们报告了中国东南部浙江省南部庆元新发现的早白垩世植物化石。根据次生木质部的解剖结构，我们将采集自西山头地层（最早的白垩纪，最早的早白垩世）的新木化石归属于田氏、朱氏和王氏。清远的新材料缺乏明显的生长环或树脂管，在管胞的径向壁上有混合型点蚀，有raucarioid横场点蚀和单列射线。它被认为是已灭绝的针叶树科箭竹属的木材，生长在干旱到半干旱的环境中。证据还表明，在整个早白垩世，箭竹科植物在中国东南部的植被中发挥了重要作用。

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引用次数: 0