As the index fossils in Middle to Late Ordovician, the classification and phylogeny of lituitids have been long debated. There have been several cladistic analyses of the phylogeny of different groups of 'nautiloid' cephalopods, including classification at lower taxonomic levels, generic affinities and their evolutionary path at higher taxonomic levels. However, a systematic and comprehensive analysis is still pending, and many taxa have never been investigated. Lituitid cephalopods are distinguished from other Ordovician cephalopods by their specific conch shape and ornaments. Most of them have a coiled or cyrtoconic part at the early growth stage, and then develop the uncoiled or fully straight conch at the late stage. As the index fossils in Middle to Late Ordovician, the classification and phylogeny of lituitids have been long debated. Recently, Dr. FANG Xiang and colleagues from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), and researchers from Universitat Zürich, University of Helsinki, Charles University in Prague and Mahasarakham University, conducted phylogenic analysis on Lituitida (Cepahlopoda), based on the large amount materials from South China. This work has been published in Journal of Systematic Palaeontology. The first cladistic analysis of the order Lituitida based on published was presented, as well as some new, material. Three clades are recovered within the ingroup of lituitids, Sinoceras, Ancistroceras and Lituites; the former group correspond to the family Sinoceratidae, and the latter two to the Lituitidae. "The topology shows that the Sinoceratidae represents the basal branch, while the Lituitidae represents a monophyletic, derived clade", Dr. FANG Xiang says, "Furthermore, we describe new material of four species (three of which are newly defined) in four genera of the order Lituitida from the well-exposed, Middle to Upper Ordovician of Hubei (South China). Tyrioceras longicameratum from South China is the first reported occurrence of Tyrioceras in China, which has significant palaeogeographical implications." This research is supported by Chinese Academy of Sciences Strategic Priority Research Program and National Natural Science Foundation of China. Reference: Fang, X.*, Pohle, A., Kroger, B., Aubrechtová, M., Burrett, C., Zhang, Y.B., Zhang, Y.D., 2021. Phylogeny of Middle–Late Ordovician lituitid cephalopods based on cladistic analysis. Journal of Systematic Palaeontology, 19(9): 633–350. https://doi.org/10.1080/14772019.2021.1944354. Cladistic analysis on Lituitida (Cephalopoda) Rhynchorthoceras yizanense sp. nov. from Datianba Formation, Sangzhi, Hunan Province Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The study provides a fundamental revisions to the traditional Permian terrestrial depositional history and chronostratigraphy of the North China block, and provide a new timeline and important insights for the history of continental collision, floral turnovers, and paleoclimate change as recorded in the North China block. The study provides a fundamental revisions to the traditional Permian terrestrial depositional history and chronostratigraphy of the North China block, and provide a new timeline and important insights for the history of continental collision, floral turnovers, and paleoclimate change as recorded in the North China block. The North China block occupied northerly tropical to subtropical paleolatitudes, marginal to the Paleo-Asian Ocean (PAO), during the critical Cisuralian (298.9-273.0 Ma) transitions from an icehouse to a greenhouse world. The late Carboniferous to Permian marine and marginal-marine to terrestrial sequences in North China preserve highly diverse and abundant plant fossils in addition to their significant economic hydrocarbon resources. These characteristics provide a unique opportunity to investigate the interactions among terrestrial biotic evolution, regional tectonics, and global climate change during a critical period of geologic history. However, poor constraints on age and correlation have hampered a deep understanding of those events in the North China block. In the absence of diagnostic marine fossils from key intervals, stratigraphic correlation within and beyond North China has relied on uncalibrated palynostratigraphy and phytostratigraphy and magnetostratigraphy. Detrital zircon geochronology by U-Pb in situ analyses from Permian volcaniclastic sandstones generally lacked the necessary precision or stratigraphic range to place reliable constraints on depositional ages. Recently, the Late Paleozoic research group from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), Nanjing University and other researchers from China, USA and Canada, report high-precision U-Pb zircon geochronology by the chemical abrasion–isotope dilution–thermal ionization mass spectrometry (CA-ID-TIMS) method focused on bentonitic tuffs from the Permian succession in North China. New high-precision U-Pb geochronology necessitates major revisions to the temporal framework for the Permian terrestrial system in North China. The research results were recently published in the international academic journal Geology. The Upper Shihhotse Formation spans the latest Asselian to the early Kungurian, as opposed to its previous Wordian to Wuchiapingian age assignments. A major depositional gap during the late Cisuralian to Guadalupian in the northern North China block may have been caused by convergent tectonics associated with the closure and/or subduction of the PAO. The great loss of highly diverse and abundant Cathaysian floras and the widespread invasion of the Angaran floras under arid climate conditions in the North China block happened during the late Cisuralian to Guadalupian, but its exact timing is uncertain due to the long hiatus. The Cisuralian global aridification may have been associated with extensive LIP volcanism and the rise of atmospheric CO2 in the waning stages of the LPIA. The research was supported by the Strategic Priority Research Programs (B) of the Chinese Academy of Sciences. Reference: Q. Wu, J. Ramezani, H. Zhang*, J. Wang, F. Zeng, Y. Zhang, F. Liu, J. Chen, Y. Cai, Z. Hou, C. Liu, W. Yang, C. M. Henderson, S. Shen*,2021, High-precision U-Pb age constraints on the Permian floral turnovers, paleoclimate change and tectonics of North China. Geology 49, 677–681. https://doi.org/10.1130/G48051.1 Figure 1. Compilation of Permian global events in parallel with Earth system changes in the North China block. Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
A new report was recently published in the international journal Global and Planetary Change on the pattern of vegetation turnover during the end-Triassic mass extinction on the basis of fern communities from South China. A new report was recently published in the international journal Global and Planetary Change on the pattern of vegetation turnover during the end-Triassic mass extinction on the basis of fern communities from South China. The end-Triassic mass extinction (ETME) is one of the five most severe extinction events in Earth history and caused the disappearance of ca. 80% of all species. The terrestrial ecosystems were also greatly affected by this extinction, but the severity of the land plant diversity loss is not well understood. Although compared with palynology data, plant macrofossils usually have a limited stratigraphic resolution, but tracked their species diversity and lived environment can provide a more intuitive and effective method for studying the extinction rate and evolution mode of terrestrial vegetation. Recently, an international research team leading by Prof. WANG Yongdong from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), Dr. ZHOU Ning, Prof. ZHANG Xingliang, from the Department of Geology of Northwest University, China and Prof. Wolfram Kürschner from Department of Geosciences, University of Oslo have investigated the diversity and ecology of fern during the Triassic-Jurassic (Tr–J) transition in the Sichuan Basin of South China and focused for the first time on the impact of the end-Triassic mass extinction event on the fern communities. The researchers collected fossil fern records, approximately 67 species ascribed to 16 genera of eight families, from 16 localities of the Rhaetian Xujiahe Formation to the lowermost Jurassic Zhenzhuchong Formation. The results indicate that a gradual decline at both the genus and species levels of macro-microflora of ferns at ETME with no obvious mass extinctions in the Sichuan Basin. However, the fern and palynological data show a clear vegetation turnover after the end-Triassic in the Sichuan Basin demonstrated that the response of vegetation changes in places far away from CAMP volcanism. The multivariate statistical approaches (principal coordinates analysis, cluster analysis, network analysis) for fern macro-remains and spores data infer a warm and humid climate during the Rhaetian. The significant increase of typical dry-resistant taxa across the Tr-J boundary, indicating a dryer environment at the earliest Jurassic. This study was jointly supported by the Strategic Priority Research Program (B) of the Chinese Academy of Sciences, the National Natural Science Foundation of China, State Key Programme of Basic Research of Ministry of Science and Technology, China and SKLPS State Key Lab Funding of NIGPAS. Reference: Ning Zhou, Yuanyuan Xu, Liqin Li, Ning Lu, Pengcheng An, Mihai Emilian Popa, Wolfram Michael Kürschner*, Xingliang Zhang, Yongdong Wang*, 2021. Pattern of vegetation turnover during the end-Triassic mass extinction: Trends of fern communities from South China with global context. Global and Planetary Change. Volume 205, October 2021, 103585. https://doi.org/10.1016/j.gloplacha.2021.103585. The diversity changes of fern species during Triassic–Jurassic transition in the Sichuan Basin and the scatter diagrams illustrating the agreement between the fern macro-remains and spores in the northeastern Sichuan basin. Left：Cluster dendrogram and PCoA biplots showing the diversity of (A) fern macro-remains (species level) and (B) fern spores (genera level) ; Right: Networks of co-occurring of (A) fern macro-remains (species level) and (B) fern spores (genera level) based on correlation analysis. Sketch drawing of some fern species from the Upper Triassic in the Sichuan Basin A. Dictyophyllum nilssoni；B. Marattia muensteri； C. Hausmannia emeiensis；D. Danaeopsis fecunda Sketch drawing of some fern species from the Upper Triassic and Lower Jurassic in the Sichuan Basin A. Coniopteris tiehshanensis；B. Todites kwangyuanensis；C. Cynepteris lasiophora；D. Phlebopteris xiangyuensisContact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The research expanded our understanding of the morphological diversity and geographical distribution of mixopterids. Eurypterids (Arthropoda: Chelicerata), normally known as sea scorpions, are an important extinct group of Paleozoic chelicerate arthropods. As a star animal in the Silurian sea (about 430 million years ago), its evolutionary history and paleoecological significance have always attracted attentions of both researchers and the public. Mixopterids are a remarkable group of eurypterids characterized by extremely specialized prosomal appendages. These limbs were presumably used for prey-capture, like the ‘catching basket’ formed by the spiny pedipalps of whip spiders. However, in contrast to their popularity, our knowledge of these bizarre animals is limited to only four species in two genera which all based on a few fossil specimens from the Silurian Laurussia 80 years ago. Recently, postgraduate WANG Han, Prof. WANG Bo and other researchers from China, German and England described a new mixopterid, Terropterus xiushanensis gen. et sp. nov. from the Lower Silurian of South China. Their finding represents the first mixopterids in Gondwana, and also the oldest mixopterids. The research expanded our understanding of the morphological diversity and geographical distribution of mixopterids. The research results were recently published as a cover paper in the international academic journal Science Bulletin. Terropterus is relatively large, estimated to have been nearly a meter in length. It bears particularly enlarged prosomal limb III, characterized by a unique arrangement of spines on it. The well-preserved appendages and other body parts fossils provided new evidences for expanding morphological diversity of Mixopteridae. By morphological comparison and phylogenetic analysis, researchers suggested more complex evolutionary relationships of this group than previously thought. Terropterus, a large arthropod with "sharp weapon", may have been playing an important role of top predators in Early Silurian shallow marine of South China. Meanwhile, the first Gondwanan mixopterid- along with other eurypterids from China and some undescribed specimens- suggests an under-collecting bias in this group. Future work, especially in Asia, may reveal a more cosmopolitan distribution of mixopterids and perhaps other groups of eurypterids. This research was supported by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Mr. YANG Dinghua (from NIGPAS) made the artist’s reconstruction. Reference: Wang Han *, Dunlop J., Gai Zhikun, Lei Xiaojie, Jarzembowski E. A., Wang Bo *, First mixopterid eurypterids (Arthropoda: Chelicerata) from the Lower Silurian of South China, Science Bulletin, https://doi.org/10.1016/j.scib.2021.07.019Fig.1 Cover image of Science Bulletin. (Reconstruction drawing by Dinghua Yang) Fig.2 Terropterus xiushanensis. (a, c, d, e, f: appendages; b: reconstruction drawing, dorsal and ventral views; g: genital operculum and the genital appendage) Fig. 3 Result of the phylogenetic analysis. (The position of Terropterus xiushanensis is highlighted in blue) Contact: LIU Yun, PropagandistEmail: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Anthrophyopsis Nathorst 1878 is an extinct but representative Late Triassic gymnosperm genus with uncertain systematic affinities and poorly understood morphology and anatomy. Since its earliest report by Nathorst in 1878, this fossil has been documented worldwide. However, the taxonomic statuses and the leaf morphological variation of this fossil plant remain questionable. Anthrophyopsis Nathorst 1878 is an extinct but representative Late Triassic gymnosperm genus with uncertain systematic affinities and poorly understood morphology and anatomy. Since its earliest report by Nathorst in 1878, this fossil has been documented worldwide. However, the taxonomic statuses and the leaf morphological variation of this fossil plant remain questionable. Recently, an international research team led by Prof. WANG Yongdong (Nanjing Institute of Geology and Palaeontology, Chinese Academy of Science(NIGPAS) ), collaborated with Prof. Mihai E. Popa from University of Bucharest of Romania, and Prof. ZHANG Tingshan’s team (Southwest Petroleum University of China), has published a new study in international journal Review of Palaeobotany and Palynology. In this research, we carried out a comprehensive systematic study of Anthrophyopsis and investigated the significance of its tempo-spatial distribution pattern. The team collected several well-preserved fossil material belonging to Anthrophyopsis from the Upper Triassic Xujiahe Formation in Guangyuan City of northern Sichuan Basin, South China. The newly collected specimens show leaves with incisions which even can generate a unipinnate leaf architecture (Figs. 1, 2). Wang says, “these specimens show various outlines with depths of incision for different leaves, pointing to transitional shapes between entire and lobed margins.” This enables a detailed and updated morphological diagnosis emendation of this fossil at genus and species level. Based on this, a new reconstruction of its type species Anthrophyopsis crassinervis was carried out with emphasis of its heteromorphic leaf morphologies (Fig. 3). The re-investigation on the global fossil record shows that among 16 species of Anthrophyopsis documented worldwide, only three of them are valid species (including Anthrophyopsis crassinervis, A. tuberculata and A. venulosa). Other four species need further revision, and nine species are invalid. In addition, Anthrophyopsis has a short stratigraphic range and confined to Upper Triassic sequences, from the Carnian to the Rhaetian, and it has a distinct stratigraphic significance. Anthrophyopsis possibly originated from the South China Block during the Carnian, migrated along the northern frame of the Tethys realm, and finally arrived in Middle East and Europe. The short stratigraphic range of Anthrophyopsis in the Southern Floristic Province (SFP) implies a climate differentiation between the SFP and the Northern Floristic Province (NFP) during the Late Triassic (Fig.4). The limited occurrences of valid Anthrophyopsis species in the Southern Floristic Province of China during the Late Triassic indicate that this genus represents a sensitive stratigraphic and palaeoclimatic marker. This study was co-sponsored by the National Natural Science Foundation of China, Strategic Priority Research Program (B) of the Chinese Academy of Sciences and the State Key Laboratory of Palaeobiology and Stratigraphy. Reference: Xu Yuanyuan, Mihai E. Popa*, Zhang Tingshan, Lu Ning, Zeng Jianli, Zhang Xiaoqing, Li Liqin, Wang Yongdong*, 2021. Re–appraisal of Anthrophyopsis (Gymnospermae): New material from China and global fossil records. Review of Palaeobotany and Palynology, 292(3): 104475. DOI: 10.1016/j.revpalbo.2021.104475. Fig.1 Anthrophyopsis crassinervis from Guangyuan area of northern Sichuan Basin, South China, showing showing almost entire margin with crenation Fig.2 Anthrophyopsis crassinervis from Guangyuan area of northern Sichuan Basin, South China, showing thick midrib with secondary vein meshes and leaf margin with deep incisions
Fig. 4 Palaeogeographic map showing the distribution of genus Anthrophyopsis around the world during the Late Triassic and its suggested migration routes. Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The western Liaoning region is known as one of the most significant fossil localities for the Jurassic osmundaceous rhizome remains in the Northern Hemisphere. Recently, a new species of osmundaceous rhizome, Claytosmunda zhangiana sp. nov. was reported with associated fungal remains represented by fungal hyphae in this spectacular osmundaceous rhizome. The research team led by Prof. WANG Yongdong (Nanjing Institute of Geology and Palaeontology, CAS), Dr. TIAN Ning (Shenyang Normal University), and Dr. JIANG Zikun (Chinese Academy of Geological Sciences) has carried out a systematic study on a structurally preserved permineralized osmundaceous rhizomes from the Jurassic of western Liaoning. This new finding results were published in the international journal Review of Palaeobotany and Palynology. The results not only further enriches the record of fossil diversity of Mesozoic osmundaceous rhizomes in China, but also contributes to further understanding the evolution of plant–fungal interactions in the Jurassic forest understorey ecosystem. The fossil material was collected from the Middle Jurassic Tiaojishan Formation in western Liaoning Province, NE China, ca. 160 Ma. Prof. WANG says, “the fossil specimen is represented by a rhizomatous stem consisting of a pith, a dictyoxylic siphonostele, a two-layered cortex, and a mantle of petiole bases”. A remarkably specialized heterogeneous petiolar sclerotic ring, whose abaxial side is occupied by a dumbbell-shaped thick-walled fiber arch, characterizes this new fossil species. This results helps for exploring the anatomical diversity of petiolar sclerotic rings of the Mesozoic and extant osmundaceous plants. Additionally, five major types of petiolar sclerotic rings are recognized. Specifically, the fungal remains, represented by branched hyphae and a kind of saprophytes, are found within the fern rhizome. This represents the first report of fungal remains associated with osmundaceous rhizomes in China. This study was jointly supported by National Natural Science Foundation of China, the Strategic Priority Research Program (B) of the CAS, the Liaoning Revitalization Talents Program, and the State Key Laboratory of Palaeobiology and Stratigraphy (NIGPAS, CAS). Reference: Tian, N.*, Wang, Y.D.*, Jiang, Z.K., 2021. A new permineralized osmundaceous rhizome with fungal remains from the Jurassic of western Liaoning, NE China. Review of Palaeobotany and Palynology, 290: 104414. Doi: 10.1016/j.revpalbo.2021.104414 (*corresponding author).
Fig.1 Claytosmunda zhangiana sp. nov. from the Middle Jurassic of western Liaoning Province, NE China Fig.2 Anatomical details of the petiole bases of Claytosmunda zhangiana sp. nov. Fig.3 Sketch drawing of the petiole bases of Claytosmunda zhangiana sp. nov. Fig.4 Fungal hyphae found within the permineralized osmundaceous rhizome
The late Neoproterozoic to the Early Cambrian is a key turning point in the evolution of the earth's environment and life. Great changes have taken place in the whole biosphere, atmosphere and hydrosphere. After the Neoproterozoic Glaciation, the sulfur isotope of seawater sulfate showed the largest positive anomaly in geological history. The values of δ34S fluctuates between 30‰ and 35‰, and sometimes even reach 45‰. This phenomenon was first discovered in Yudomski Formation in Siberia, which is called Yudomski Event. During this period, the sulfur isotope of sulfate in seawater changed dramatically, and its process was also recorded by sulfate deposition, the huge evaporite belt extended from Oman in the Middle East to Iran, Pakistan, northern India, and even to Sichuan Basin. Recently, MENG Fanwei, Associate Professor of Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences (NIGPAS), cooperated with Professor Krzysztof Bukowski of AGH University of technology in Poland and Professor Naveed Ahsan of Punjab University in Pakistan to continuously analyze the gypsum deposition of Salt Range Formation from late Neoproterozoic to Early Cambrian in Salt Range area in northern Pakistan of India plate, The abnormal event was first found in the strata in northern Pakistan, which is also the first systematic study of the event in Pakistan. The research results were recently published in the European academic journal Geological Quarterly. It is found that the sulfur isotope of gypsum in Salt Range Formation ranges from 35‰ to 30‰ from Late Proterozoic to Early Cambrian, and gradually decreases to about 30‰ with the formation from bottom to top. The same sulfur isotope anomaly has been found in Tarim Basin, northwestern China, which supports this previous speculation about the affinity between the Indian plate and the Tarim Basin. The study of sulfur isotopes of evaporites in Salt Range area in northern Pakistan of the Indian plate not only reveals that the global consistency of the Yudomski event, but also for the correlation of evaporite stratigraphy within the globe and the recovery of world paleogeography, as well as the sources of hydrocarbon sources formed at the same time. This study is also a report of the results of the investigation of salt range and other areas in northern Pakistan by NIGPAS from February 21 to March 6, 2018.This work was financially supported by the National Natural Science Foundation of China, the Basic Frontier Scientific Research Program of the Chinese Academy of Sciences, AGH University of Science and Technology and by the Bureau of International Co-operation, Chinese Academy of Sciences. Reference: Fanwei Meng, Zhili Zhang, Krzysztof Bukowski*, Qingong Zhuo, Naveed Ahsan, Saif Ur-Rehman and Pei Ni, 2021. A strongly positive sulphur isotopic shift in late Ediacaran-early Cambrian seawater: evidence from evaporites in the Salt Range Formation, north ern Pakistan. Geological Quarterly, 65: 30. http://dx.doi.org/10.7306/gq.1598. Fig, 1 Gypsum in Salt Range Formation, northern Pakistan Fig. 2 The sulfur isotope data of gypsum in Salt Range Formation
How did the camouflage skills of insects originate and evolve? The new reports of mantle behavior in two major groups of insects (the rodent and hemiptera toadstool families) in the Mesozoic advance the record of their mantle behavior to before the great radiation of flowering plants. How did the camouflage skills of insects originate and evolve? The new reports of mantle behavior in two major groups of insects (the rodent and hemiptera toadstool families) in the Mesozoic advance the record of their mantle behavior to before the great radiation of flowering plants. Animals have evolved several strategies in prey-predator interactions due to selective pressures, such as mimicry and camouflage. Both mimicry and camouflage enable animals to effectively reduce the probability of detection by prey and predators. As the most diverse animal group, insects have evolved such strategies through various pathways including utilizing specialized morphologies. Plant-like mimesis and debris-carrying camouflage are rather common adaptations within insects. Plant-like mimesis, an effective way to hide by mimicking leaves, sticks or bark, is rife among resting katydids, walking sticks and leaf insects. Debris-carrying camouflage is most common in Neuroptera and Hemiptera, in which larvae match their life-supporting environment by decorating themselves with exogenous debris. Although several fossil insects have been reported showing plant-like mimesis and debris-carrying camouflage from the Mesozoic, the abundance of taxa involved is much rarer than in modern groups, and more investigation is needed. Recently, Mr. XU Chunpeng, supervised by Prof. WANG Bo from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), cooperated with researchers from Wuhan University and University of Kansas, have reported a pygmy mole cricket (Tridactylidae) mimicking spike mosses or leafy liverworts from mid-Cretaceous Kachin amber (approximately 99 million years ago). The behavioural mimicry interpretation is further confirmed by Siamese Neural Network analysis. Additionally, the research reported a diverse insect assemblage with debris-carrying camouflage from mid-Cretaceous Kachin amber, comprising six nymphs of Psocodea and a nymph of Gelastocoridae. These researches have been published on Gondwana Research and Historical Biology. The new find pygmy mole cricket Phyllotridactylus wangi displays mimicry with some coeval spike mosses or leafy liverworts which are spore-bearing plants and quite diverse in mid-Cretaceous Kachin amber. Phyllotridactylus wangi exhibits a morphological resemblance to these leafy liverworts and spike mosses in gross morphology, including the shape of leaves. The most striking feature is the remarkable inflation of the metafemur, which resembles leaf lobes of some spike mosses laterally or dorsolaterally. Additionally, the inflation made by the mesofemur and mesotibia also resembles the central “leaflets” of spike mosses or leafy liverworts. Critically, Mesozoic plant mimesis in Tridactylidae is supported by Siamese Network analysis. In order to analyze the resemblance of P. wangi with model plants, the researchers developed a new approach to utilize the Siamese Network of Deep Learning, which can measure the dissimilarity between two images by calculating the “distance” between image pairs and provide a dissimilarity value. The deep learning algorithms are used to quantify the mimicry of fossil insects in this study for the first time, providing a new model for quantifying the mimesis of fossil insects and novel insights into exploring the early evolution of mimicry. "After pre-training the Siamese Network by part of TLL (a similar image dataset) and fine-tuning it by part of LIMD (a dataset contains image pairs of extant insects and their model mimicry plants), the remainder part of LIMD is input and a dissimilarity threshold value of mimic definition for extant insects is calculated" , Prof. WANG Bo says, "we fine-tuned the dissimilarity threshold value of mimic definition for extant insects based on the FIMD (a dataset contains image pairs of fossil insects and their model mimicry plants), and calculated the dissimilarity threshold value of mimic definition for fossil insects". Among these specimens, six nymphs of Psocodea and a nymph of Gelastocoridae exhibit debris-carrying behaviour. Psocodean nymphs are belonged to three Morphotypes, which might stick sand and organic material with their setae on their backs. Gelastocorid nymph shows a very flat form, being both dorsally and ventrally covered with unequal-sized sand grains and plant debris. It has a flat abdominal tergum forming a defined space for the trash packet components, which can facilitate carrying debris more stably on the dorsal surface. These finds are the oldest fossil records of Psocodea and Gelastocoridae with debris-carrying camouflage, extending the geological range of this behaviour within Psocodea and Gelastocoridae by approximately 80 million years. Together with previously known records, these fossils demonstrate that most extant debris-carrying insects (eight groups with direct camouflage) had evolved exogenous camouflage by the mid-Cretaceous. Mimicry and camouflage are important in insects to avoid detection by both prey and predators. By the Cretaceous, many new predaceous arthropods (including some spiders, lacewing larvae, and ants) and vertebrates (including lizards, birds, and mammals) were present. These results suggest that elaborate mimicry and camouflage were already widespread among insects in the mid-Cretaceous ecosystems during the rise of angiosperms, probably responding to similar selective pressures as those experienced by their extant counterparts. We thank WANG Ning and GE Chang for kindly providing the specimens, and YANG Dinghua for reconstructions of fossil specimens.
References: Xu, C., Wang, B., Fan, L., Jarzembowski, E.A., Fang, Y., Wang, H., Li, T., Zhuo, D., Ding, M., Engel, M.S. (2021). Widespread mimicry and camouflage among mid-Cretaceous insects. Gondwana Research. https://doi.org/10.1016/j.gr.2021.07.025. Fan, L., Xu, C., Jarzembowski, E. A., Cui, X. (2021). Quantifying plant mimesis in fossil insects using deep learning. Historical Biology, 1-10. https://doi.org/10.1080/08912963.2021.1952199. Figure 1: Pygmy mole cricket Phyllotridactylus wangi gen. et sp. nov. (b, d, f) and potential model plants (a, c, e, g) from mid-Cretaceous Kachin amber. Figure 2: Psocodean nymphs (a–f) and gelastocorid nymph (g, h) from mid-Cretaceous Kachin amber. Figure 3: Geological range of insect groups that display plant mimesis and debris-carrying camouflage behaviour. Figure 4: Ecological reconstruction of gelastocorid nymphs and a tridactylid. Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Well-developed Devonian deposits are widely spread in west and east marginal areas of the Junggar Basin, North Xinjiang, which acts are representative areas of Devonian flora of North China. The Devonian strata of the eastern and western sides of the Junggar Basin belong to different palaeoblocks paleogeographically, and scholars have been conducting more in-depth studies on plant fossils of the West Jungga.However, few knowledge of plant fossils from the Devonian of East Junggar hinders understanding to its flora and further comparison. Hence, it is necessary to carry on stratigraphical and palaeotological study to the Devonian of East Junggar, for the significances of early land plant evolution and palaeogeography. Recently, the Devonian Investigation Group (DIG) of Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), led by Prof. XU Honghe, conducted a systematic palaeontological study based on materials from the Upper Devonian of East Junggar, Fuyun, Xinjiang. The related research results were published online in the international journal Review of Palaeobotany and Palynology. In this study, the lycopsid Gilboaphyton (Protolepidodendrales) is discovered as a new species. Gilboaphyton fuyunensis, which is characterized by pseudo-spirally longitudinal–hexagonal to fusiform leaf base, slender and entirely marginal leaf with two lateral up turned segments occurring at its one third portion from the base. Using palynological result the study dated and correlated the plant fossil-bearing strata. The research also visualized the spatio-temporal distribution pattern of Gilboaphyton base on its global occurrence data. It is suggested that Gilboaphyton was probably originated in southeastern Laurentia in the Early-Middle Devonian, and spread to the Siberia and Gondwana blocks towards northeast and southwest respectively in the Late Devonian to Early Carboniferous. The similar spatio-temporal distribution of Gilboaphyton and Archaeosigillaria suggest that the two genera might belong to the same plant. Reference: Bing-Cai Liu, Jiao Bai, Yao Wang, Ning Yang, Hong-He Xu *, 2021. On the discovery of Gilboaphyton (Lycopsida) from the Upper Devonian of East Junggar, Xinjiang, and its global distribution. Review of Palaeobotany and Palynology. 292, 104473. https://doi.org/10.1016/j.revpalbo.2021.104473. Fig 1. Fieldwork photo of Devonian investigation Group NIGP-CAS fieldwork in East Junggar, Xinjiang Fig 2. Gilboaphyton fuyunensis Liu et Xu and spores from the Upper Devonian Kaxiweng Formation, Fuyun, Xinjiang, China. Fig 3. Occurrences of Gilboaphyton (pink disks) and Archaeosigillaria (yellow disks) species plotted on the Early-Middle Devonian (A) and Late Devonian–Early Carboniferous (B) palaeogeographic maps.
The oil shale of the Tongchuan Formation has high potential for oil production. The results of this analysis also provide an important basis for the formation and preservation environment restoration of the oil shale of the Tongchuan Formation, and the related research results have been recently published in the international journal Geological Journal. The oil shale of the Tongchuan Formation has high potential for oil production. The results of this analysis also provide an important basis for the formation and preservation environment restoration of the oil shale of the Tongchuan Formation, and the related research results have been recently published in the international journal Geological Journal. The Ordos Basin is the second largest sedimentary basin in China, located in the western part of the North China Craton. The Tongchuan and Yanchang formations are two dominant sedimentary sequences in the Ordos Basin, occurring in the Middle Triassic and Upper Triassic series, respectively. The organic-rich shales in the Yanchang Formation have been considered to be the main hydrocarbon source rock in the Ordos Basin, a great deal of research works have been done on its sedimentary environment. Similarly, thick organic-rich shales are also developed in the Middle Triassic Tongchuan Formation, which immediately underlies the Upper Triassic Yanchang Formation. The earliest known appearance of a Mesozoic-type of tropical, multi-levelled lacustrine ecosystem is also reported from these shales. Up till now, studies of the depositional environment of the Tongchuan shales have been lacking, although it is of significance for understanding the formation and preservation of organic-rich shales and lacustrine fossils. Recently, the research team led by Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS) carried out a systematic studies focused on high-resolution carbon (δ13Corg) and sulphur (δ34Spy) isotope analysis as well as undertook total organic carbon (TOC)/pyrite contents and pyrite morphology investigation, and framboidal pyrite size measurements in Tongchuan Formation shales of the Bawangzhuang section of the southern Ordos Basin. Remarkably high TOC (23 ± 9%) and pyrite (7 ± 3%) contents were obtained from the shales, which indicate a large amount of organic carbon and pyrite burial and high primary productivityduring shale deposition. These TOC values are even higher than those from the Yanchang Formation (6%–14%), indicating the Middle Triassic Tongchuan Formation also have high oil-generating potential. And the low varying δ13Corg values (31.8‰ to 28.1‰; average value of 29.1 ± 0.7‰) in Tongchuan Formation suggest balanced and consistent carbon cycles and the high TOC content is probably produced by abundant photoplankton during shale deposition. Dr. ZHAO Xiangdong say, “framboids are the dominant pyrite morphology in the pyrite crystals and show large and variable mean diameters (7.0 ± 1.7 μm to 14.3 ± 6.8 μm) across the section, indicating oxic–dysoxic bottom water during shale deposition.” δ34Spy with narrow and less variable values, ranging from 4.1‰ to 4.9‰. Integrated with pyrite content and morphological patterns, consistent δ34Spy values probably demonstrate a relatively open environment for the formation of sedimentary pyrite, and thus a shallow chemocline that was quite close to the water-to-sediment interface during shale deposition. Overall, the organic-rich shales of the Tongchuan Formation were probably deposited under oxic–dysoxic bottom-water conditions. Shallow chemocline depth combined with moderately high sedimentation rate and high primary productivity may have played crucial roles in the deposition and formation of the organic-rich shales in the Tongchuan Formation. The shallow chemocline also facilitates the fossil preservation in a lacustrine environment. Relevant research work was jointly funded by the Chinese Academy of Sciences, the National Natural Science Foundation of China, and the China National Petroleum Company. Reference: Zhao, X., Wang, W., Xie, G., Pan, S., Jarzembowski, E. A., & Zheng, D. (2021). Depositional environment of Middle Triassic organic-rich shales in the Ordos Basin, Northwest China. Geological Journal, 1–12. https://doi.org/10.1002/gj.4215 Figure 1: Field photographs of the Bawangzhaung section. Figure 2: Petrographic photographs of the Bawangzhuang section. Figure 3: Geochemical profiles at the Bawangzhuang section. Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
