Recently, Prof. WANG Yongdong, from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, and Associate Professor ZHOU Ning from the Department of Geology, Northwest University, in collaboration with other colleagues from Anhui University of Science and Technology, as well as Chengdu University of Science and Technology, conducted a systematic palaeobotanical study on well-preserved Pagiophyllum maculosum Kendall fossils from the Lower Jurassic in the Zigui Basin, western Hubei Province, South China. This study marks the first discovery of this species in China, yielding materials with leafy shoots bearing cuticles, male and female cones. The results has been published in the international journal Review of Palaeobotany and Palynology.Pagiophyllum is a form genus of extinct conifers with scale-like, spirally arranged leaves, widely distributed from the Late Permian to the Late Cretaceous. Due to its leaf morphology resembling several conifer families (e.g., Cheirolepidiaceae, Cupressaceae, Araucariaceae), its taxonomic placement has long been uncertain. Although some species have been assigned to the extinct family Cheirolepidiaceae, most fossils are preserved as isolated leafy shoots lacking cuticular details and reproductive structures, hindering definitive natural classification and understanding of their ecological adaptations.Recently, Prof. WANG Yongdong, from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, and Associate Professor ZHOU Ning from the Department of Geology, Northwest University, in collaboration with other colleagues from Anhui University of Science and Technology, as well as Chengdu University of Science and Technology, conducted a systematic palaeobotanical study on well-preserved Pagiophyllum maculosum Kendall fossils from the Lower Jurassic in the Zigui Basin, western Hubei Province, South China. This study marks the first discovery of this species in China, yielding materials with leafy shoots bearing cuticles, male and female cones. The results has been published in the international journal Review of Palaeobotany and Palynology.Initially reported only from the Middle Jurassic of Yorkshire, UK, Pagiophyllum maculosum lacks definitive records of cuticles and reproductive organs owing to poor preservation. Here, the research team utilize optical, fluorescence, and scanning electron microscopy, alongside micro-CT, to elucidate the morphology and anatomy of its vegetative shoots, female and male cones, and epidermal structures. The study shows that the leaves of P. maculosum are triangular to ovoid, helically and imbricately arranged (Figs. 1-2). The abaxial leaf surface bears stomatal rows with sunken stomata surrounded by 4-6 subsidiary cells; epidermal cells are irregularly polygonal (Figs. 3-4). The female cone is elliptical, approximately 2.5 cm long, consisting of an estimated 36-40 helically arranged bract-scale complexes (Figs.2). The male cone is subspheroidal, about 6.5 mm in diameter, with peltate microsporophylls producing typical Classopollis-type pollen (Fig.4). Based on these morphological and anatomical features, the research team presents a whole-plant reconstruction of P. maculosum (Fig.5).Different Pagiophyllum species exhibit leaf morphological characteristics that are convergent with those of the families Cupressaceae, Taxodiaceae, Araucariaceae, and Cheirolepidiaceae. This has led to a complex taxonomic history, with Pagiophyllum species being assigned to different families. To assess the morphological similarities among the related leaf specimens, a hierarchical clustering analysis was performed based on a set of discrete character states (Fig.6). The analysis was conducted based on a morphological matrix of 18 characters for 29 fossils and 6 extant species from Taxodiaceae and Araucariaceae. The clustering analysis confirms that the leaf architecture of Pagiophyllum maculosum is clearly assignable to the Brachyphyllum-type morphospace. Its strong morphological affinity with Brachyphyllum and Elatides supports its inclusion within a coherent eco-morphological group. This classification is consistent with earlier studies that place P. maculosum within the Cheirolepidiaceae. Therefore, this fossil material provides direct evidence for the natural taxonomic placement of this form genus and offers new insights into the whole-plant morphology of Jurassic Cheirolepidiaceae.Notably, P. maculosum exhibits typical xeromorphic features, including thick cuticles, sunken stomata, and reduced free leaf parts. Furthermore, the plant assemblage from the same horizon is dominated by gymnosperms such as ginkgoaleans, bennettitaleans, and conifers, with ferns being exceptionally rare. This dominance of gymnosperms, coupled with the xeromorphic traits of P. maculosum, suggests an arid or semi-arid climate during the depositional period. These findings provide important evidence for understanding Early Jurassic paleoclimate and the ecological adaptations of cheirolepidiaceous conifers.This research was jointly funded by the National Natural Science Foundation of China, and the National Key Research and Development Program of China.Reference: Ning Zhou*, Yongdong Wang*, Yuanyuan Xu, Pengcheng An, Ziheng Wu. Whole-plant reconstruction of Pagiophyllum maculosum (Cheirolepidiaceae) from the Early Jurassic of China: Insights from new fossil material. Review of Palaeobotany and Palynology, 348 (2026) 105540. https://www.sciencedirect.com/science/article/pii/S0034666726000424.Fig. 1. Fossil specimens of Pagiophyllum maculosum from the Lower Jurassic in Zigui of Hebei Province, ChinaFig. 2. Female cone of P. maculosumFig.3. Fluorescence micrograph of P. maculosum leaf cuticlesFig. 4. P. maculosum (A–D) Scanning electron micrograph of the cuticle, showing epidermal cells and sunken stomata; (E, F) Light microphoto of Classopollis pollenFig. 5. Restoration of P. maculosum with leafy shoots, male cone, female cone, seed scale and Classopollis-type pollenFig.6. Hierarchical clustering based on a set of discrete character states for the potential fossil relatives and extant conifers, with extant species indicated by an asterisk (*). Different colors represent distinct clusters based on morphological similarity
Recently, Associate Professor WANG Yaqiong from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), together with Senior Researcher Robin J. Smith from the Lake Biwa Museum, Japan, Senior Researcher Byung-Do Choi from Daegu National Science Museum, South Korea, and researcher from Nanjing University, conducted a systematic study of ostracod fossils from the Lower Cretaceous Lisangou Formation in the Guyang Basin, Inner Mongolia. The research team identified a freshwater ostracod assemblage consisting of fifteen species from ten genera of three superfamilies. The study provided the first precise biostratigraphic age constraint for the Lisangou Formation, indicating a late Aptian age. Furthermore, the ontogeny of Cretaceous Darwinuloidea was recognized and documented for the first time.The North China Craton (NCC) is one of the important ancient geological units in East Asia. During the Late Mesozoic, the NCC underwent a series of major tectonic processes, including intense lithospheric thinning, extensional basin development, and large-scale magmatism, known as the “destruction of the North China Craton”. These processes not only profoundly reshaped the regional geological framework but also had a significant impact on the evolution of terrestrial ecosystems.Most previous studies on the evolution of terrestrial life and its responses to the NCC destruction predominantly focused on fossils from Konservat-Lagerstätten, with less emphasis on more ubiquitous fossil groups that are abundant, widely distributed, and preserved under relatively generic conditions. While fossils from Konservat-Lagerstätten offer detailed anatomical structures that are crucial for studying the morphology and evolution of significant fossil groups, these assemblages are typically confined to specific burial environments, locales, and time periods, thus complicating continuous, high-resolution studies of regional biological evolution, biodiversity, and biogeographical transitions over extended timescales. Research on Early Cretaceous non-exceptional fossil groups in the NCC offers a more comprehensive perspective on the relationship between terrestrial life evolution and the NCC destruction. The rift basins along the northern margin of the NCC preserve the most complete Early Cretaceous terrestrial sedimentary successions rich in non-exceptional fossil group - ostracods. These ostracod-bearing deposits provide a unique opportunity to explore the relationship between terrestrial ecosystem evolution and the destruction of the NCC from a broader and more general perspective.Recently, Associate Professor WANG Yaqiong from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), together with Senior Researcher Robin J. Smith from the Lake Biwa Museum, Japan, Senior Researcher Byung-Do Choi from Daegu National Science Museum, South Korea, and researcher from Nanjing University, conducted a systematic study of ostracod fossils from the Lower Cretaceous Lisangou Formation in the Guyang Basin, Inner Mongolia. The research team identified a freshwater ostracod assemblage consisting of fifteen species from ten genera of three superfamilies. The study provided the first precise biostratigraphic age constraint for the Lisangou Formation, indicating a late Aptian age. Furthermore, the ontogeny of Cretaceous Darwinuloidea was recognized and documented for the first time.The result was published in Palaeoworld.In recent years, the research group have undertaken extensive field studies in several Cretaceous basins along the northern margin of the NCC where the destruction was most severe, gathering substantial fossil ostracod collections. This study provides a comprehensive revision of the ostracod assemblage from the Lisangou Formation in the Guyang Basin. The ostracod assemblage of the Lisangou Formation includes several typical freshwater taxa, including Cypridea, Lycopterocypris, Candona, Rhinocypris, Timiriasevia, and Alicenula?. Some of these taxa have important biostratigraphic significance for the Early Cretaceous terrestrial deposits of East Asia. Based on ostracod biostratigraphic correlations, the first well-constrained biostratigraphic age is suggested for the Lisangou Formation, placing it in the late Aptian.This study provided the first record of juvenile stages (A-1 to A-3 instars) of Cretaceous Darwinulidae Alicenula? custella and identified potential male individual in Alicenula? sp. A. The family Darwinulidae has garnered significant interest over the past three decades due to its potential status as one of only three “ancient asexual” groups in the animal kingdom. It has been suggested that the group has been reproducing asexually for over 200 million years due to the lack of male fossils in Mesozoic sediments. Therefore, this study not only provides new fossil evidence for understanding the long-term evolutionary history and systematic complexity of Darwinulidae but also challenges the hypothesis that this group maintained asexual reproduction for more than 200 million years.This study also identified at least two darwinuloidean mass-mortality events coinciding with their reproductive period provides compelling evidence that short-lived environmental catastrophes episodically disrupted an otherwise stable fluvial–lacustrine system during the deposition of the Lisangou Formation.This study advances our understanding of Early Cretaceous fossil ostracods from the destruction area of the NCC, and provides essential material for investigating the potential links between terrestrial biodiversity and the craton destruction.This research was supported by the National Natural Science Foundation of China.Reference: Yaqiong Wang*, Huazheng Zhu, Robin J. Smith, Byung-Do Choi, 2026. Lower Cretaceous Ostracoda (Crustacea) of the Lisangou Formation in the Guyang Basin, North China: Implications for Biostratigraphy and Palaeoenvironment. Palaeoworld 35, 201140. https://doi.org/10.1016/j.palwor.2026.201140.Fig 1. Lower Cretaceous lithostratigraphic units of the Guyang Basin and stratigraphic columns showing lithologies and position of ostracod samples from the Lisangou Formation in the Lisangou-Yangduiyaozi outcrop (A) and two sections (B and C) newly exposed due to road construction. Photographs from the studied sections B and C showing the positions of the ostracod samples. Sample numbers in black indicate those that yielded specimens in the present work. Lower Cret. = Lower Cretaceous, Fm.= Formation.Fig 2. Selected non-Cypridea species from the Lisangou FormationFig 3. Alicenula? custellaFig 4. Size-range plot of carapace dimensions of Alicenula? custella, Darwinula stevensoni and Vestalenula cylindrica and line drawings of the carapace outlines of these three species from ontogeny stages A-3 to adult. The size and outline data of D. stevensoni and V. cylindrica are from Smith and Kamiya (2008).
A new study led by Dr. LUO Cihang, under the supervision of Prof. WAGN Bo and Prof. ZHANG Haichun at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), now reports amber from the Middle Devonian Hujiersite Formation of Xinjiang, northwestern China. The study was conducted in collaboration with the team of Prof. XU Honghe and Dr. YANG Huiyuan from the team of Prof. CUI Xingqian at Shanghai Jiao Tong University, together with other international collaborators. The newly discovered Hujiersite amber is approximately 385 million years old. It extends the confirmed fossil record of amber by about 65 million years and challenges the traditional view that amber was produced only by seed plants. The finding provides direct fossil evidence for the early evolution of plant resin production, terpene-based resin biosynthesis, and chemical defense mechanisms in early land plants. Amber is fossilized plant resin. In living plants, resin plays important roles in sealing wounds and protecting tissues against microbes, wildfires, and wood-boring organisms. Once fossilized, resin may preserve organic molecules for hundreds of millions of years and, in some cases, entrap tiny organisms such as insects, spiders, and plant fragments. For this reason, amber has long been regarded as a “time capsule” for ancient terrestrial ecosystems. Amber (resinite) are also important in coal petrology and petroleum geology. They are hydrogen-rich organic components that can undergo thermal evolution and generate liquid hydrocarbons at relatively low maturity levels. Their study therefore provides useful evidence for understanding hydrocarbon generation and assessing the petroleum potential of organic-rich strata. Despite its scientific importance, amber is extremely rare in Paleozoic rocks. Classical accounts of amber have generally regarded fossil resin as a product of seed plants, including gymnosperms and angiosperms. Until now, the earliest widely accepted amber record was from the Late Carboniferous of the United States, about 320 million years ago. The origin and earliest evolution of amber have therefore remained poorly constrained.A new study led by Dr. LUO Cihang, under the supervision of Prof. WAGN Bo and Prof. ZHANG Haichun at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), now reports amber from the Middle Devonian Hujiersite Formation of Xinjiang, northwestern China. The study was conducted in collaboration with the team of Prof. XU Honghe and Dr. YANG Huiyuan from the team of Prof. CUI Xingqian at Shanghai Jiao Tong University, together with other international collaborators. The newly discovered Hujiersite amber is approximately 385 million years old. It extends the confirmed fossil record of amber by about 65 million years and challenges the traditional view that amber was produced only by seed plants. The finding provides direct fossil evidence for the early evolution of plant resin production, terpene-based resin biosynthesis, and chemical defense mechanisms in early land plants.The amber samples were collected from a cutinitic coal seam in the Ancient Petroleum Reservoir Section of the Hujiersite Formation, northwestern Junggar Basin, Xinjiang. This region has yielded the Hujiersite Flora, an important Middle Devonian plant assemblage that includes lycopsids, zosterophylls, iridopteridalean, and progymnosperms. These fossils make the Hujiersite Formation a key locality for understanding the structure and evolution of Devonian terrestrial vegetation. From about 10 kilograms of coal, the research team manually extracted hundreds of tiny amber particles under ultraviolet light. Most particles are only 0.1–0.5 millimetres in diameter, with the largest reaching about 1.5 millimetres. Under natural light, they range from light yellow to dark brown and vary from translucent to opaque. Under ultraviolet light, they show a distinct blue fluorescence, sharply contrasting with the surrounding black coal matrix.Because some organic matter in coal can resemble resin in appearance or fluorescence, the team further analysed the samples using Fourier-transform infrared spectroscopy (FT-IR) and gas chromatography–triple quadrupole mass spectrometry (GC-MS/MS). FT-IR spectra showed that the Hujiersite samples share key absorption features with modern and fossil resins, including signals associated with aliphatic C–H bonds, carboxyl-related C=O and O–H bonds, and methyl and methylene C–H bonds. These results indicate that the overall chemical structure of the samples is consistent with resin or amber. The spectra also lack several features typical of some angiosperm ambers, such as the 887 cm⁻¹ peak common in fabalean ambers and the 1360–1400 cm⁻¹ triplet and 1050 cm⁻¹ peak characteristic of dipterocarpaceous ambers. Instead, the Hujiersite amber shows closer spectral similarity to gymnosperm resins, including those of Pinaceae, Cupressaceae, and Araucariaceae. Organic geochemical analyses further confirmed the resinous nature of the samples. The Hujiersite amber contains abundant sesquiterpenoids, diterpenoids, and naphthalenic acids. Several abietane-type diterpenoids and their derivatives, which are commonly associated with conifer-type resins, were identified. By contrast, the samples lack typical angiosperm resin markers such as oleanane-type triterpenoids. Taken together, the FT-IR and geochemical data demonstrate that these particles are real fossil resin, namely amber, and that their chemical composition is most similar to gymnosperm, especially conifer-type resins.The age of the Hujiersite amber is especially important. It predates the origin and radiation of seed plants, meaning that it was not produced by typical seed plants. Instead, it was most likely derived from other vascular plants. Based on the composition of the Hujiersite Flora, possible source plants include progymnosperms and arborescent lycopsids. This suggests that some Middle Devonian vascular plants had already evolved the capacity to produce complex terpene-rich resins.The discovery also sheds new light on the ecological context in which resin production may have evolved. Devonian was a critical interval in the expansion of land plants and the increasing complexity of terrestrial ecosystems. During this time, plants became larger, rooting systems deepened and became more complex, secondary wood evolved, and large leaves began to appear. At the same time, early land plants faced physical injury, wildfires, and pathogen attacks. Evidence for extensive arthropod herbivory on Devonian vascular plants remains limited, suggesting that the earliest evolution of resin may have been driven less by herbivorous arthropods and more by wound sealing, recovery after fire or mechanical damage, and defence against fungal or microbial invasion.The Hujiersite amber not only pushes back the earliest confirmed record of amber, but also highlights the need to re-examine Paleozoic coal seams and fine-grained deposits for minute resin particles. Early amber may have been extremely small, locally distributed, and easily overlooked. By combining microscopic observation, FT-IR spectroscopy, and molecular organic geochemistry, this study establishes a robust approach for identifying tiny deep-time amber particles and provides key fossil evidence for the early evolution of plant chemical defence, resin biosynthesis, and terrestrial ecosystems.This work was supported by the National Natural Science Foundation of China, the Strategic Priority Research Program of the Chinese Academy of Sciences, and other funding sources.Reference: Luo Cihang, Yang Huiyuan, Xu Honghe, Yang Zixiao, Wang Shengyu, Engel M. S., Liu Bingcai, Jarzembowski E. A., Boudinot B. E., Cui Xingqian, Zhang Haichun, Wang Bo. 2026. The earliest amber from the Middle Devonian of China. https://doi.org/10.1126/sciadv.aeh1266.Fig.1 Middle Devonian Hujiersite amber from Xinjiang, China. The amber occurs as minute particles in coal, mostly 0.1–0.5 mm in diameter, and shows strong blue fluorescence under ultraviolet light.Fig.2 FT-IR spectra of Hujiersite amber and representative fossil and modern resins. Fourier-transform infrared spectroscopy shows that Hujiersite amber shares key absorption features with modern and fossil resins and displays spectral signals closer to gymnosperm resins.Fig.3 Chemical composition of Hujiersite amber. GC-MS/MS analysis reveals abundant sesquiterpenoids, diterpenoids, and naphthalenic acids, supporting the identification of the samples as real amber.
Recently, the PhD candidate SONG Siyu, supervised by Professor ZHENG Daran (Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences), has preliminarily recovered the Early Cretaceous terrestrial biodiversity of the QOB based on fossils from the Fengjiashan (Shangxian Basin), Baiwan (Baiwan Basin), and Nanzhao formations (Mashiping Basin) collected in the QOB, and further discussed their palaeobiogeographical and palaeoecological implications. The results were published online in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.As the control center of the modern ecosystem of China, the evolution of the Qinling Orogenic Belt (QOB) influenced the development of East Asian terrestrial ecosystems during the Late Mesozoic. The Early Cretaceous Jehol Biota, distributed along the Shangdan Suture Zone in the QOB, provides key clues for reconstructing the Early Cretaceous terrestrial ecosystems in central China, yet it has lacked research for nearly three decades.Recently, the PhD candidate SONG Siyu, supervised by Professor ZHENG Daran (Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences), has preliminarily recovered the Early Cretaceous terrestrial biodiversity of the QOB based on fossils from the Fengjiashan (Shangxian Basin), Baiwan (Baiwan Basin), and Nanzhao formations (Mashiping Basin) collected in the QOB, and further discussed their palaeobiogeographical and palaeoecological implications. The results were published online in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.This study reveals new fossils of dinosaur footprints, bivalves, clam shrimp, gastropods, insects, and megaplants, reconstructs the Jehol Biota in the QOB, and establishes a regional stratigraphic framework. Key findings include abundant invertebrate and plant fossils from the Shangxian Basin in Shaanxi Province, as well as the first report of the Early Cretaceous dinosaur footprint and angiosperm fossils from Henan Province. The invertebrate fossil assemblages include the bivalve Arguniella-Sphaerium assemblage, the clam shrimp Eosestheria-Diestheria assemblage, the gastropod Probaicalia vitimensis-Ptychostylus-Reesidella robusta assemblage, and the middle Jehol Entomofauna. These indicate that the Lower Cretaceous in the QOB could be correlated with the Yixian and Jiufotang formations in western Liaoning, and that the Jehol Biota reached the QOB during its middle evolutionary stage.Within the QOB, the Jehol Biota occur eastward in the Shangxian, Baiwan, and Mashiping basins along the Shangdan Suture Zone. The clam shrimp Eosestheria-Diestheria assemblage co‑occurs in the Shangxian and Baiwan basins, whereas the Jehol Entomofauna is present in all three basins. This distribution pattern suggests the existence of a potential paleo‑drainage system connecting basins in the QOB, which provided suitable palaeoecological conditions for biological flourishing and bridged the southward dispersal of the Jehol Biota in central China.This research was supported by the National Natural Science Foundation of China and the Strategic Priority Research Program (B) of the Chinese Academy of Sciences.Reference: Song, S., Zhang, X., Teng, X., Li, T., Yu, T., Li, J., Xue, Y., Liu, P., Fang, R., Zhao, X., Zheng, D.*, 2026. Early Cretaceous Jehol Biota in the Qinling Orogenic Belt: palaeobiogeographical and palaeoecological implications. Palaeogeography, Palaeoclimatology, Palaeoecology, 698, 113939. https://doi.org/10.1016/j.palaeo.2026.113939.Fig.1 Clam shrimp fossils from the Fengjiashan Formation of the Shangxian BasinFig.2 Insect and megaplant fossils from the Baiwan Formation of the Baiwan BasinFig.3 Dinosaur footprint, insect and megaplant fossils from the Nanzhao Formation of the Mashiping BasinFig.4 Regional correlation of the Lower Cretaceous in the Qinling Orogenetic Belt
Recently, an international research team led by Professor ZHANG Hua of the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), published a study in Earth and Planetary Science Letters that employs magnesium isotopes (δ26Mg) as a novel tracer to constrain inter‑ocean connectivity during the P–Tr transition and its influence on ecosystem resilience. The first author is Associate Professor HU Zhongya of Tongji University, and the corresponding author is Professor ZHANG Hua.The Permian–Triassic (P–Tr) transition, approximately 252 million years ago, witnessed the most severe mass extinction event in Earth’s history, with more than 80% of marine species eliminated and ecosystems virtually collapsed. The crisis is widely attributed to large‑scale volcanic eruptions, including the Siberian Traps and acidic volcanism in the Tethyan realm, which injected massive CO2 and volatile substances into the atmosphere, triggering rapid global warming, ocean acidification, and intense carbon‑cycle perturbations. Rising temperatures further reduced oxygen solubility and enhanced water‑column stratification, weakening oceanic circulation and deep‑water ventilation, leading to widespread marine anoxia and even local euxinia.However, a long‑standing question remains: did the severity of this global catastrophe vary among ocean basins due to differences in circulation intensity and connectivity? This issue is critical for understanding the spatiotemporal patterns of the extinction and the subsequent biotic recovery.Recently, an international research team led by Professor ZHANG Hua of the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), published a study in Earth and Planetary Science Letters that employs magnesium isotopes (δ26Mg) as a novel tracer to constrain inter‑ocean connectivity during the P–Tr transition and its influence on ecosystem resilience. The first author is Associate Professor HU Zhongya of Tongji University, and the corresponding author is Professor ZHANG Hua.Magnesium is a major constituent of seawater, second only to sodium, and has a long residence time of approximately 13 million years in the modern ocean. This vast marine Mg reservoir imparts a strong geochemical “inertia” to the open ocean – even under global environmental perturbations, the Mg isotope composition of the open ocean remains remarkably stable. In contrast, published records show that short‑term (<1 Myr) significant variations in seawater δ26Mg are almost exclusively associated with restricted basins. Therefore, Mg isotopes have recently emerged as a powerful proxy for identifying transient basin restriction.During the P–Tr transition, the marine Mg cycle was highly dynamic, influenced by enhanced continental weathering, widespread dolomitization, and reverse weathering. These processes are all accompanied by significant Mg isotope fractionation, providing a theoretical basis for using δ26Mg to trace paleo‑ocean connectivity.The research team systematically analysed Mg isotopes from three major paleo‑oceans – the Paleo‑Tethys, Neo‑Tethys, and Panthalassa. Sampling sections included the Saiq section in Oman and the Naluch Nala section in the Salt Range of Pakistan (Neo‑Tethys), as well as the Kamura and Taho sections in Japan (Panthalassa). All sections preserve complete P–Tr successions with well‑constrained conodont biostratigraphy and carbon isotope correlations.The results reveal a fundamental divergence: seawater δ26Mg remained stable (−0.4‰ to −0.3‰) in the Neo‑Tethys and Panthalassa across the P–Tr transition, whereas it increased by more than 0.5‰ in the Paleo‑Tethys. Previous work by the same group (Hu et al., 2021) demonstrated that the pronounced δ26Mg rise in the Paleo‑Tethys reflects intensified dolomitization under global warming – light 24Mg was preferentially incorporated into dolomite, enriching the residual seawater in heavy 26Mg.This stark inter‑basin contrast indicates that different ocean basins responded in fundamentally different ways to the same global climate perturbation. The Neo‑Tethys maintained effective water exchange with the Panthalassa, and its seawater chemistry was buffered by the vast Panthalassa reservoir. In contrast, the Paleo‑Tethys was relatively restricted, so the local dolomitization signal was amplified and clearly recorded in its Mg isotope composition.To further quantify the buffering capacity of different basins, the team constructed a box model coupling the Mg cycle and water exchange. The model integrates Mg fluxes from riverine input, dolomitization, high‑temperature and low‑temperature alteration, and incorporates inter‑basin exchange parameters.Simulations show that the residence time of Mg in seawater is the key parameter controlling the amplitude of δ26Mg variation. At Early Triassic seawater Mg concentrations of 10–50 mmol/kg, the residence time is estimated at 2–10 Myr. For a shorter residence time (~2 Myr), a roughly three‑fold reduction in exchange is sufficient to produce the observed isotope shift; for a longer residence time (~5 Myr), nearly two orders of magnitude of restriction are required to generate a similar change.More importantly, the model quantitatively evaluates the buffering capacities of the different basins. In the relatively restricted Paleo‑Tethys, enhanced dolomitization over ~0.75 Myr consumed ~3.15 × 1018 mol of Mg, depleting the basin’s Mg reservoir by ~20%. In contrast, imposing the same relative increase in dolomitization flux on the vast Panthalassa/Neo‑Tethys system would result in a depletion of <5%, producing a δ26Mg change of <0.1‰ – consistent with the observed stability. These results demonstrate that the open ocean’s large Mg reservoir provides strong chemical buffering, whereas restricted basins are highly sensitive to environmental perturbations.Stable seawater chemistry is crucial for the survival and recovery of marine organisms. Palaeoecological evidence indicates that shallow‑water carbonate platforms in the Neo‑Tethys maintained well‑oxygenated conditions after the extinction, hosting diverse benthic assemblages dominated by crinoids, bivalves, gastropods, brachiopods, and ostracods. These communities suggest that the Neo‑Tethys, being effectively connected to the Panthalassa, provided a relatively stable chemical environment that served as a refugium for surviving taxa.In contrast, the restricted setting of the Paleo‑Tethys amplified multiple environmental stresses: enhanced dolomitization consumed alkalinity, potentially accelerating local ocean acidification; limited circulation further exacerbated anoxia; and elevated nutrient inputs from continental weathering accumulated in the semi‑closed basin, promoting eutrophication and widespread oxygen deficiency. The occurrence of pyrite in shallow‑water carbonates supports persistent suboxic to anoxic conditions in the Paleo‑Tethys.This study provides the first inter‑basin geochemical evidence for oceanic differentiation during the P–Tr transition, revealing that the marine system did not respond homogeneously to the global crisis but instead exhibited a fundamental structural divergence. The findings deepen our understanding of the recovery mechanisms following the largest mass extinction in Earth’s history and introduce a new isotopic tool for paleo‑oceanographic circulation reconstruction.This work was supported by the National Natural Science Foundation of China and the China Scholarship Council.Reference: Zhongya Hu, Weiqiang Li, Robert J. Newton, Sylvain Richoz, Yasufumi Iryu, Satoshi Takahashi, Takumi Maekawa, Zhiguang Xia, Shouye Yang, Shu‑Zhong Shen, Hua Zhang*. 2026. Magnesium isotopes constrain connectivity and environmental resilience among ocean basins during the Early Triassic. Earth and Planetary Science Letters 690: 120191. https://doi.org/10.1016/j.epsl.2026.120191.Fig.1 Comparison of δ²⁶Mg variations in typical dolomite sections from the Paleo‑Tethys, Neo‑Tethys and Panthalassa oceansFig.2 (A–C) Geochemical variations during the P–Tr transition (from literature); (D) Reconstructed seawater δ²⁶Mg from dolomite records (this study); (E–G) Element and isotope mass‑balance modeling testing the buffering capacity of Panthalassa vs. Paleo‑Tethys
Recently, a research team led by Professor CAI Chenyang from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), collaborated with research institutions across the United Kingdom, the United States, the Czech Republic, Spain, Italy and other countries. Leveraging large-scale genome sequencing, construction of an ultra-large molecular matrix and multi-dimensional statistical validation, the team assembled a phylogenomic dataset with broad taxonomic coverage for insect evolution, precisely resolving the evolutionary position of Zoraptera on the insect Tree of Life. The findings were published online in the international journal Proceedings of the Royal Society B.Zoraptera, commonly known as angel insects, represents one of the most enigmatic insect orders. These minute, soft-bodied insects exhibit both winged and apterous morphs and live gregariously. Distributed mainly across tropical regions worldwide, they dwell under bark, in decaying wood and leaf litter, with fewer than 50 extant species recorded globally. Discovered more than a century ago, the phylogenetic placement of Zoraptera has long remained a central contentious puzzle in insect evolutionary research. Over the past decade, morphological and molecular analyses have unanimously placed Zoraptera within Neoptera, yet conflicting evolutionary hypotheses persist regarding its relatedness to other polyneopteran lineages. This long-standing debate, dubbed the "century-old problem", highlights the immense challenge of resolving its evolutionary affinities.Recently, a research team led by Professor CAI Chenyang from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), collaborated with research institutions across the United Kingdom, the United States, the Czech Republic, Spain, Italy and other countries. Leveraging large-scale genome sequencing, construction of an ultra-large molecular matrix and multi-dimensional statistical validation, the team assembled a phylogenomic dataset with broad taxonomic coverage for insect evolution, precisely resolving the evolutionary position of Zoraptera on the insect Tree of Life. The findings were published online in the international journal Proceedings of the Royal Society B.The researchers sampled 89 extant species covering all major polyneopteran clades, alongside 23 distant outgroups. Highly conserved single-copy orthologous genes were filtered, assembled and concatenated to build an ultra-large polyneopteran phylogenetic matrix with the most comprehensive taxon sampling and balanced lineage representation to date. Based on this extensive gene dataset, the team systematically evaluated diverse molecular evolutionary models, quantified and corrected phylogenetic biases induced by across-site compositional heterogeneity, and compared topological perturbations arising from different partitioning schemes and heterogeneity-correcting models.The results demonstrate that the widely accepted mainstream Haplocercata hypothesis—positing Zoraptera and Dermaptera as sister groups forming the basal polyneopteran lineage—only holds when compositional heterogeneity across sequence sites is ignored. Support for this hypothesis declines markedly once site-heterogeneous models capable of mitigating such systematic errors are applied. Under the optimal evolutionary model, Zoraptera consistently emerges as the earliest-diverging lineage at the root of Polyneoptera, while Dermaptera and Plecoptera form the clade Dermoplectopterida, the sister group to all remaining polyneopterans. Topology tests and cross-model comparisons jointly confirm the robustness of the polyneopteran phylogenetic framework proposed herein, laying a critical foundation for reconstructing the ancestral morphological and biological traits of polyneopterans and elucidating their early evolutionary radiation.The team adopted a multi-layered independent validation framework to cross-verify the conclusions. First, multispecies coalescent models yielded an identical topology to the maximum-likelihood tree inferred from the ultra-large matrix. Second, the jackknife resampling test was systematically applied for the first time to an ultra-large insect genomic matrix, repeatedly confirming that the recovered evolutionary framework is robust to perturbations of the matrix and analytical approaches. The highly stable polyneopteran phylogeny established in this study provides a core quantitative analytical framework for reconstructing ancestral polyneopteran body plans and deciphering patterns of their early radiation.This research was funded by the National Key R&D Program of China.Reference: Yehao Wang, Erik Tihelka, Petr Kočárek, Michael S. Engel, Jesus Lozano-Fernandez, Zi-Wei Yin, Omar Rota-Stabelli, Diying Huang, Davide Pisani, Philip C.J. Donoghue and Chenyang Cai* (2026) Phylogenomics resolves the century-old ‘Zoraptera problem’: Zoraptera as the earliest diverging lineage of Polyneoptera. Proc. R. Soc. B 291: 2025.3174. https://doi.org/10.1098/rspb.2025.3174.Fig.1 Zorapterans and their habitatsFig.2 Impacts of across-site compositional heterogeneity on polyneopteran phylogeny; the left panel shows previous hypotheses, and the right panel presents the novel topology recovered in this studyFig.3 Shifts in statistical support for the two competing hypotheses and comparisons of model fitFig.4 Systematic jackknife resampling tests applied to an ultra-large insect genomic matrix for the first time; congruent topological relationships within Polyneoptera recovered consistently via both coalescent and maximum-likelihood analyses
Recently, Associate Professor WANG Yaqiong from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), and Associate Professor ZHONG Yuting from Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, together with collaborators from Liupanshui Normal University and Nanjing University, conducted zircon SIMS U–Pb dating of tuff layers from the Lower Cretaceous succession in the Liuhe Basin, Jilin Province. High-precision ages were obtained for the Lamenzi, Dashatan, and Baodaqiao formations, yielding ages of 127.1 ± 0.9 Ma, 124.6 ± 1.2 Ma, and 122.1 ± 1.4 Ma, respectively. The result was published in Cretaceous Research.The North China Craton (NCC) is a key geological unit in East Asia. Its large-scale destruction during the Late Mesozoic, characterized by lithospheric thinning, large-scale magmatism and structural deformation, is widely considered to be closely related to the subduction of the Paleo-Pacific Plate. This deep geodynamic process not only triggered widespread magmatic activity and rifting but also profoundly influenced the evolution of terrestrial ecosystem.Recently, Associate Professor WANG Yaqiong from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), and Associate Professor ZHONG Yuting from Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, together with collaborators from Liupanshui Normal University and Nanjing University, conducted zircon SIMS U–Pb dating of tuff layers from the Lower Cretaceous succession in the Liuhe Basin, Jilin Province. High-precision ages were obtained for the Lamenzi, Dashatan, and Baodaqiao formations, yielding ages of 127.1 ± 0.9 Ma, 124.6 ± 1.2 Ma, and 122.1 ± 1.4 Ma, respectively. The result was published in Cretaceous Research.These results establish, for the first time, a robust chronostratigraphic framework for the Lower Cretaceous strata of the Liuhe Basin, providing new temporal constraints for dating fossil-bearing horizons of the Jehol Biota sensu lato and for understanding the evolution of Early Cretaceous rift basins in East Asia.The Liuhe Basin is a small rift basin located in the northeastern part of the North China Craton (NCC), preserving fossil assemblages of the Jehol Biota sensu lato (including gastropods, bivalves, fishes, and turtles). However, the depositional ages of these fossil-bearing strata have long remained poorly constrained because of the lack of reliable geochronological data, limiting our understanding of basin evolution and regional tectonic-ecological interactions.In this study, zircon SIMS U–Pb dating was performed on tuff layers interbedded within sedimentary successions of the Lamenzi, Dashatan, and Baodaqiao formations. The results indicate that the Lamenzi Formation was deposited during late Hauterivian, the Dashatan Formation during early Barremian, and the Baodaqiao Formation during the late Barremian to early Aptian. Combined with previously published ostracod biostratigraphic data, the study further constrains the ages of the Xiahuapi Dianzi and Hengtongshan formations to Aptian, while the Heiwaizi Formation may extend into early Albian.This study also documents that the sedimentary evolution of the Liuhe Basin records a transition from volcanic-dominated deposition to clastic sedimentation at ~122 Ma, marking a shift from syn-rift magmatism to post-rift conditions. Regional comparison indicates that this transition exhibits an eastward-younging trend across rift basins along the northern NCC, consistent with progressive lithospheric extension driven by rollback of the paleo-Pacific plate.The newly established geochronological framework not only refines the Lower Cretaceous stratigraphic timescale of East Asia but also provides important temporal constraints for investigating how deep Earth geodynamic processes influenced surface basin evolution and terrestrial ecosystem development. Furthermore, this study supports the hypothesis that the spatiotemporal evolution of the Jehol Biota sensu lato on the NCC may have been closely linked to the destruction of the craton, providing a new basis for understanding the coupling relationships among tectonic activity, environmental change, and biological evolution in East Asia during the Early Cretaceous.This research was supported by the National Key Research and Development Program of China and the National Natural Science Foundation of China.Reference: Yu-Ting Zhong, Ya-Qiong Wang*, Jia-Jun Mo, Huazheng Zhu, 2026. Chronostratigraphic constraints on the Lower Cretaceous volcano-sedimentary succession of the Liuhe Basin: implications for the Jehol Biota sensu lato and destruction of the North China Craton. Cretaceous Research, 186: 106429. https://doi.org/10.1016/j.cretres.2026.106429Fig. 1 A. Tectonic map showing distribution of Cretaceous basins in NE Asia; active rift basins distributed in northern NCC (modified from Meng et al., 2022, figure 1). B. Simplified geological map of the Liuhe Basin, showing the distribution of major stratigraphic units and sampling locations (modified from the 1: 250,000 geological map of the Hailong area).Fig. 2 A–C. Overview photographs of the sampled sections; D–F. Field occurrences of tuff samples 2025TF-5, 2025TF-6, and 2025TF-7, respectively; G–H. Photomicrographs of sample 2025TF-5 under plane-polarized light and cross-polarized light, respectively; I. Photomicrograph of sample 2025TF-7 under plane-polarized light; J. Stratigraphic column showing lithology, thickness, and sampling horizons of individual formations (thickness based on Xu et al., 2019, table 1). Fsp: feldspar; Qtz: quartz.Fig. 3 Stratigraphic correlation of Lower Cretaceous sequences in northern NCC, showing volcanic and volcaniclastic rocks in the lower part and clastics in the upper (modified from Zhou et al., 2021, figure 4) (ages data based on Zhou et al., 2021; Meng et al., 2022; Zhong et al., 2025, references therein and this study); subduction process of paleo-Pacific plate during the Early Cretaceous, and its controls on destruction of the NCC (modified from Zhu et al., 2017, figure 5) (Geochronological chart based on International Chronostratigraphic Chart v 2024/12, Cohen et al., 2013).
Recently, a research team led by Prof. LI Tao from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), in collaboration with scientists from the University of Bristol, Nanjing University, and Shanghai Jiao Tong University, innovatively integrated coral elemental ratios with a quantitative biomineralization model. They established a new quantitative correction method for seawater Ba concentration based on the Ba/Ca ratios of cold-water corals, significantly advancing the application of cold-water coral geochemistry in paleoenvironmental reconstruction. The relevant findings have been published in the internationally renowned journal Earth and Planetary Science Letters.Cold-water corals are widely distributed in the global deep ocean. The barium-to-calcium (Ba/Ca) ratio in their skeletons serves as a key proxy for tracing seawater Ba concentration, and thus for reconstructing past ocean productivity and deep ocean circulation. However, existing calibration curves exhibit significant genus offsets and data scatter, mainly due to the Rayleigh fractionation effect during coral biomineralization, which leads to non-equilibrium partitioning of elements such as Ba and Sr between the skeleton and seawater, causing the skeletal record to deviate from the true seawater signal.Recently, a research team led by Prof. LI Tao from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), in collaboration with scientists from the University of Bristol, Nanjing University, and Shanghai Jiao Tong University, innovatively integrated coral elemental ratios with a quantitative biomineralization model. They established a new quantitative correction method for seawater Ba concentration based on the Ba/Ca ratios of cold-water corals, significantly advancing the application of cold-water coral geochemistry in paleoenvironmental reconstruction. The relevant findings have been published in the internationally renowned journal Earth and Planetary Science Letters.By integrating elemental composition data from nearly one hundred cold-water coral specimens of different genera collected from various ocean regions, including the Southern Ocean, the North Atlantic, and the equatorial Atlantic, along with the corresponding physicochemical parameters of the ambient seawater, the team found that under the same seawater Ba concentration, different coral genera exhibit significant and systematic differences in Ba/Ca ratios. Moreover, these differences show a strong positive correlation with Sr/Ca ratios, indicating that the Rayleigh fractionation effect is the key factor controlling the inter‑genus offsets. Based on this, the team introduced a quantitative biomineralization model (Fig. 1) to correct the Ba/Ca ratios using paired Sr/Ca data, successfully establishing a unified and robust cold-water coral Ba/Ca–seawater Ba concentration calibration curve. This significantly improves the paleoceanographic reconstruction capability of the cold-water coral Ba/Ca proxy.The team further conducted cross‑validation using cold-water coral samples collected from different water depths on the Burdwood Bank seamount in the Drake Passage, Southern Ocean (Fig. 2). The results show that without correction, the seawater Ba concentrations reconstructed from Ba/Ca ratios of different coral genera at the same water depth exhibit large scatter and obvious inter‑genus offsets, deviating significantly from the measured seawater values. However, after correction using paired Sr/Ca ratios and the biomineralization model, the data from different genera converge toward the same seawater Ba concentration, and the reconstructed vertical profile of seawater Ba concentration is in much better agreement with the measured values, substantially improving the accuracy of seawater Ba concentration reconstruction.This research lays a solid foundation for the widespread application of the cold-water coral Ba/Ca proxy in reconstructing past seawater Ba concentrations, and is expected to provide key technical support for revealing the coupled relationship between ocean productivity changes and deep ocean circulation evolution during the glacial‑interglacial cycles of the late Pleistocene.This study was supported by the National Natural Science Foundation of China and the Natural Science Foundation of Jiangsu Province.Reference: Feng, Q., Li, T.*, Chen, S., Robinson, L.F., Kershaw, J., Stewart, J.A., Liu, Q., Wang, M., Chen, T., 2026. A revised calibration of cold-water coral Ba/Ca versus seawater Ba concentration using paired Sr/Ca and a biomineralization model. Earth and Planetary Science Letters 690.https://doi.org/10.1016/j.epsl.2026.120142.Fig.1 Quantitative biomineralization model for elemental ratios in cold-water corals.Fig.2 Comparison of reconstruction results from cold-water corals on the Burdwood Bank seamount in the Southern Ocean.
Under the supervision of Prof. WANG Yongdong of Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), the Ph.D. student CHEN Hongyu at NIGPAS, in collaboration with Prof. Dieter Uhl and Dr. XIE Aowei from the Senckenberg Research Institute and Natural History Museum, Germany, Dr. ZHANG Li from NIGPAS, as well as colleagues from Nanjing Center of China Geological Survey, Chengdu University of Technology has performed investigations of Ixostrobus male cones based on new material from the Qaidam Basin, NW China. This work provides a taxonomic revision based on the global fossil record, explores the spatio-temporal distribution patterns of the genus, and achieves insights into the morphological characteristics. The findings have been published in the international journal Review of Palaeobotany and Palynology.Gymnosperms are one of the most significant taxa of the Mesozoic flora worldwide. Reproductive organs, which often exhibit relatively stable morphological characteristics, provide valuable materials for investigating the taxonomic relationships and evolutionary patterns of this plant group. Ixostrobus Raciborski, a form genus, is considered as the male cone of Czekanowskiales, widely reported from the Mesozoic flora. However, because of the usually poor preservation, especially the male reproductive organs heavily affected by phenology, the understanding of their key morphological characteristics remains limited. Besides, the reports on Ixostrobus are rather scattered in literature in different languages and regions, presenting some difficulties for a comprehensive comparison of these fossil records.Under the supervision of Prof. WANG Yongdong of Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), the Ph.D. student CHEN Hongyu at NIGPAS, in collaboration with Prof. Dieter Uhl and Dr. XIE Aowei from the Senckenberg Research Institute and Natural History Museum, Germany, Dr. ZHANG Li from NIGPAS, as well as colleagues from Nanjing Center of China Geological Survey, Chengdu University of Technology has performed investigations of Ixostrobus male cones based on new material from the Qaidam Basin, NW China. This work provides a taxonomic revision based on the global fossil record, explores the spatio-temporal distribution patterns of the genus, and achieves insights into the morphological characteristics. The findings have been published in the international journal Review of Palaeobotany and Palynology.Recently, well-preserved fossil specimens of Ixostrobus have been collected from the Lower Jurassic Tianshuigou and Yinmagou formations in the northern margin of the Qaidam Basin, Qinghai Province. Based on this, the researchers conduct in-depth and detailed investigations on systematic morphology, and formally revised its generic diagnosis to clarify the key diagnostic traits and improve the accuracy of morphological descriptions.This study clarifies that the main diagnostic characteristics of Ixostrobus are represented by an axis bearing only microsporophylls without any bracts or other appendages, with pollen sacs and scales at the distal end of microsporophyll, and the pollen sacs borne on the adaxial side of microsporophyll.Based on investigations on newly collected fossil specimens of Ixostrobus cones from the Qaidam Basin in China and examination of all reported taxa, several previously assigned specimens are revised (Figs.1, 2), a new record of I. heeri is documented from the local flora (Fig.3), and a new species, I. bilobus Chen, Wang et Zhang sp. nov., distinguished by its bilobed scale, is recognized (Fig.4).A comprehensive re-appraisal of previously reported global species is conducted through direct examination of specimens and assessment of the original fossil records. Among the 18 species documented as Ixostrobus so far, 13 species are proposed to be valid, i.e., I. bilobus, I. daohugouensis, I. grandis, I. groenlandicus, I. heeri, I. laxus, I. longicalcaratus, I. longus, I. punctatus, I. schmidtianus, I. siemiradzkii, I. tunguscanum, I. whitbiensis. Among the valid species, 5 species, i.e., I. grandis, I. laxus, I. longus, I. punctatus, and I. tunguscanum, are indeed poorly preserved, which require more collections and further investigation.Geologically, Ixostrobus ranges from the Early Triassic to the Early Cretaceous, with peak in species diversity during the Early Jurassic period (Fig. 5). Geographically, Ixostrobus are widely distributed across the Northern Hemisphere, with significant occurrences in Europe (Poland, Hungary, UK, Greenland), Russia, Iran, Afghanistan, as well as Central and East Asia, indicating a primary occurrence within the warm temperate zone of eastern Laurasia at middle to high latitudes (Fig. 5).This represents the first re-appraisal of the genus Ixostrobus, and substantially advances our understanding of the Mesozoic gymnosperm diversity evolution. These findings elevate Ixostrobus to a pivotal reference taxon for reconstructing the systematics, diversification dynamics, and extinction patterns of Mesozoic gymnosperms.This study is co-sponsored by the National Natural Science Foundation of China, the Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project of China, the China Postdoctoral Science Foundation, the Basic Research Program of Jiangsu, the China Scholarship Council, and the Government of Ireland Postdoctoral Fellowship Programme.Reference information: Chen, H.Y. (陈泓宇), Wang, Y.D.* (王永栋), Zhang, L., Zhu, Y.B., Xie, A.W., An, P.C., Uhl, D., 2026. Re-appraisal of the Mesozoic male cone Ixostrobus Raciborski (Czekanowskiales) based on new material from the Qaidam Basin, NW China: New insights into systematics, diversity and spatio-temporal distribution. Review of Palaeobotany and Palynology 352, 105605. https://doi.org/10.1016/j.revpalbo.2026.105605.Fig.1 Ixostrobus siemiradzkii from the Qaidam Basin, and the illustration of holotype.Fig.2 Ixostrobus groenlandicus from the Qaidam Basin, and the illustration of holotype.Fig.3 Ixostrobus heeri from the Qaidam Basin, and the illustration of holotype.Fig.4 Ixostrobus bilobus sp. nov. from the Qaidam Basin.Fig.5 Global stratigraphic ranges and palaeogeographic distributions of the valid Ixostrobus species.
Recently, PhD candidate XUAN Qiang (Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences), under the supervision of Prof. HUANG Diying (NIGPAS), together with Prof. ZHANG Zhiqiang (Manaaki Whenua – Landcare Research, New Zealand), reported evidence of queueing behaviour in larval mites from the Cretaceous Burmese amber. In this study, adjacent individuals within the queue are connected by fine silk threads, thereby physically reinforcing the queue structure, revealing a previously unknown silk-mediated mechanism of group alignment. The mites were identified as a new genus and species within the family Erythraeidae, named Protofilum ordinatum gen. et sp. nov. The scientific results were recently published online in Proceedings of the Royal Society B: Biological Sciences.In arthropods, queueing behaviour represents a stereotypical and visually striking form of collective locomotion. This behaviour is most commonly observed in highly social insects, such as ants, termites, and lepidopteran larvae. Additionally, some non-social or sub-social arthropods can also form queues under specific ecological conditions, for example, migratory spiny lobsters in autumn and juvenile tarantulas when dispersing from their burrows. However, the fossil record of queueing behaviour in arthropods is extremely sparse. Only a few Palaeozoic marine arthropod fossils have been interpreted as possible “queues”, such as the Cambrian putative crustacean Synophalos and Ordovician and Devonian trilobites, but little is known about their function and formation mechanism. In terrestrial ecosystems, no analogous fossil record has been discovered to date, leaving the early evolution of queueing behaviour in terrestrial arthropods completely unexplored.Recently, PhD candidate XUAN Qiang (Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences), under the supervision of Prof. HUANG Diying (NIGPAS), together with Prof. ZHANG Zhiqiang (Manaaki Whenua – Landcare Research, New Zealand), reported evidence of queueing behaviour in larval mites from the Cretaceous Burmese amber. In this study, adjacent individuals within the queue are connected by fine silk threads, thereby physically reinforcing the queue structure, revealing a previously unknown silk-mediated mechanism of group alignment. The mites were identified as a new genus and species within the family Erythraeidae, named Protofilum ordinatum gen. et sp. nov. The scientific results were recently published online in Proceedings of the Royal Society B: Biological Sciences.In this fingernail-sized piece of amber, 13 larval mites are aligned head-to-tail, with the body axis of all individuals pointing in the same direction, forming an almost straight queue with only minor local deflections. These mites all possess extremely long legs, and leg-to-leg contact between adjacent individuals suggests that tactile feedback played an important role in maintaining the queue. Furthermore, the research team discovered fine thread-like structures, only 1–3 micrometres in diameter, preserved on the legs of the individuals. These threads form physical connections between adjacent individuals and may have functioned as mechanical “tethers”: when direct contact was temporarily interrupted, the silk connections could enhance cohesion between individuals, thereby stabilising the structure of the moving queue.Even more remarkably, one mite was captured in the act of spinning silk. Using high-resolution laser confocal microscopy, the team identified the silk-producing organ located on the mid-dorsal region of the cheliceral base. An elliptical glandular opening with distinctly sclerotised margins is visible, and residual filamentous secretions are preserved at the opening in some individuals. This study represents the first fossil evidence of silk utilisation in mites.The research team suggests that the queueing migratory behaviour of the fossil mites might have facilitated the superparasitism of larval mites and subsequent mate-finding in adults. Superparasitism refers to the common phenomenon where multiple larval mites parasitise the same arthropod host. Because mites have limited locomotory abilities and rely primarily on host-mediated dispersal, the establishment of a new population largely depends on the chance of encountering a mating partner. If only a single larva is transported to a new area, the probability of encountering a mate after moulting is extremely low. In contrast, superparasitism allows multiple conspecific larvae to disperse together via the same host, significantly increasing their mating opportunities after metamorphosis. In this context, queueing migration may have facilitated the coordinated location of hosts by larval mites, allowing multiple individuals to simultaneously reach and attach to the same host. The silk threads could then have acted as “safety lines”, reducing the risk of being dislodged during parasitism and host movement. This behaviour may have increased the likelihood of conspecific larval co-dispersal, thereby enhancing reproductive success and population persistence. This interpretation is further supported by another amber specimen, in which three conspecific larval mites are preserved in a linear arrangement together with a dipteran host.This paper reports queueing migratory behaviour in mite larvae from the mid-Cretaceous Burmese amber. This discovery not only represents the first fossil evidence of such behaviour from the Mesozoic, but also the earliest known fossil evidence of queueing migratory behaviour in terrestrial arthropods. This finding pushes back the evolutionary origin of queueing behaviour in terrestrial arthropods by nearly 100 million years, while also revealing unexpected behavioural complexity in early small-bodied arthropods. Together with previously reported fossil queues, this study demonstrates that queueing behaviour has evolved independently in both marine and terrestrial ecosystems in response to different ecological pressures, highlighting its adaptive significance in the evolutionary history of arthropods.This study was supported by the National Key Research and Development Program of China (2024YFF0807601) and the National Natural Science Foundation of China (42288201).Reference: Xuan, Q., Zhang, Z.-Q., Cai, C., Li, S., & Huang, D. 2026. Silk-mediated queueing migration in Cretaceous mites. Proceedings of the Royal Society B: Biological Sciences, 293: 20260271. https://doi.org/10.1098/rspb.2026.0271.Fig. 1 Migratory queue of fossil larval mites from mid-Cretaceous Burmese amber.Fig. 2 Silk-mediated connections between adjacent mites and the silk-producing apparatus.Fig. 3 Morphological details in P. ordinatum gen. et sp. nov.Fig. 4 Queueing behaviour in fossil and extant arthropods
