Recently, the Early Land Plant Evolution working group of Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), led by Prof. XU Honghe, made new progress in Late Devonian plant assemblage and floral evolution of West Junggar during the Devonian. The research result was published in Review of Palaeobotany and Palynology. The West Junggar paleo-terrain, comprised of a series of active volcanic arcs and aligned with the Kazakhstan Paleoblock, played an important role as a land bridge in global plant dispersal during the Devonian Period. Its well-developed Middle to Upper Devonian deposits yielded abundant macro- and micro- plant fossils, fostering numerous paleobotanical and palynological studies. Over the past two decades, the Middle Devonian Hujiersite Flora and the Late Devonian Zhulumute Flora were studied in detail, for providing a unique window of Devonian flora in West Junggar. Recently, the Early Land Plant Evolution working group of Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), led by Prof. XU Honghe, made new progress in Late Devonian plant assemblage and floral evolution of West Junggar during the Devonian. The research result was published in Review of Palaeobotany and Palynology. “In this study, we recognized a new Late Devonian plant assemblage based on the macro- and micro plant fossils from the Hongguleleng Formation in West Junggar, Xinjiang, China”, says XU. The Hongguleleng Flora is comprised of macroplants, cf. Hoxtolgaya, Leptophloeum rhombicum, Frenguellia eximia and Helicophyton sp., and palynomorphs dominated of retusoid and laevigate trilete spores. This Flora shows similarities with coeval ones in Laurussia, Gondwana and South China, suggesting biogeographical affinities and potential plant dispersal. “We summarized the fossils records from Mid-Late Devonian of West Junggar shows that at least two floral turnovers were documented in West Junggar during the Devonian, occurred respectively at the end of the Givetian Age and Frasnian-Famennian boundary”, XU adds. The rarefaction indicates that Zhulumute and Hongguleleng floras have potentially unreported species and needs to be further explored. This study was supported by National Key R&D Program of China and the Chinese Academy of Sciences. This study is one of series contributions to the Deep-time Digital Earth Big Science Program. Reference: Liu B.C., Wang K., Zong R.W., Bai J., Wang Y., Yang N., Wang Y., Xu H.-H. 2024. A new Late Devonian plant assemblage in West Junggar, Xinjiang, China and its floral evolution during the Devonian. Review of Palaeobotany and Palynology. 325, 105112. https://doi.org/10.1016/j.revpalbo.2024.105112.
Fig. 1 Macro- and micro plant fossils from the Upper Devonian Hongguleleng Formation, West Junggar, Xinjiang.
Fig. 2 Geologic ranges of Mid to Late Devonian macroplants in West Junggar and its flora evolution. Fig. 3 Rarefaction curves of Hujiersite, Zhulumute and Hongguleleng floras. Shaded area represents 95% confidence intervals.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Biomineralized columns, stacked in layers like a sandwich gave Cambrian brachiopod shells their strength and flexibility 520 million years ago. To gain insights into the evolution and diversity of this intricate biomineralized columnar architecture, Dr. ZHANG, Zhiliang from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS) and colleagues from China and Sweden examined exquisitely well-preserved fossils from some of the oldest families of linguliform brachiopods. The study was published in the international academic journal eLife. Biomineralized columns, stacked in layers like a sandwich gave Cambrian brachiopod shells their strength and flexibility 520 million years ago. To gain insights into the evolution and diversity of this intricate biomineralized columnar architecture, Dr. ZHANG, Zhiliang from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS) and colleagues from China and Sweden examined exquisitely well-preserved fossils from some of the oldest families of linguliform brachiopods. The study was published in the international academic journal eLife. The Cambrian, a geological period around half a billion years ago, witnessed one of the most intense bursts of animal evolution in Earth’s history. During this time, the majority of marine animal groups that we would recognise in the oceans today, emerged and diversified around the globe. One of the key advancements during this explosion of life in the Cambrian was the development of biomineralized shells. Biomineralization, refers to mineralisation that is biologically controlled, produces organic-inorganic composite skeletons and shells, the construction of which would have played a vital role in the survival and fitness of early animals. This linking of living soft organic tissues with solid earth minerals is a process that has changed the nature of Earth’s fossil record. Brachiopods, known as ‘lamp shells’ are one of the most successful biomineralized animal groups, having survived for over 500 million years. Most animal groups only have the ability to secrete a single mineral, yet brachiopods are unique animals in that they have the ability to secrete two different minerals, calcium phosphate and calcium carbonate. Although many living brachiopod species have calcium carbonate shells, the calcium phosphatic linguliform brachiopods were one of the earliest shell-bearing animal groups to appear in the fossil record. “Linguliform brachiopod shells are generally composed of an organic matrix combined with calcium phosphate (apatite) minerals. Linguliform shells are intricately composted of microscopic cylindrical columns, however the development and role of these microscopic columns in brachiopod evolution is unclear”, says Dr. ZHANG. The fossil samples include Eoobolidae, Lingulellotretidae and Acrotretidae were taken from the Cambrian Series 2 Shuijingtuo Formation of southern Shaanxi and western Hubei in South China – a region that is widely considered to be one of the centres for the origination and early dispersal of linguliform brachiopods. Their study reveals that the microscopic columns were stacked on top of each other to form a secondary layer of the shell, in what the authors refer to as the “stacked sandwich model” (because of the resemblance to the cross section of a sandwich). This stacked sandwich columnar architecture increases the shell’s toughness, flexibility, and ability to resist fractures, by filling the space in between the columns with organic material – resembling the columns and reinforced concrete often used in the construction of buildings. “Thus, we hypothesize that this efficient and economical shell architecture has likely played a significant role in the evolution of linguliform brachiopods”, says Dr. ZHANG, “it may account for the flourish of phosphatic-shelled Acrotretides in the latter half of the Cambrian, and the continued diversification of brachiopods during the Great Biodiversification Event 50 million years later.” Reference: Zhiliang Zhang *, Zhifei Zhang, Lars E. Holmer, Timothy P. Topper, Bing Pan, Guoxiang Li. 2024. Evolution and diversity of biomineralized columnar architecture in early Cambrian phosphatic-shelled brachiopods. eLife 12:RP88855, 1–32. https://doi.org/10.7554/eLife.88855. Scanning electron microscopy image of biomineralized columnar architectures and the underlying epithelial cells in early Cambrian brachiopod fossils. Image credit: Z.L. Zhang. Biomineralized columnar architectures of Cambrian Series 2 phosphatic-shelled brachiopods. Image credit: Z.L. Zhang. Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
A research group led by Prof. HUANG Diying from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences has systematically studied fossil water striders from the mid-Cretaceous of northern Myanmar (about 100 million years ago) in recent years. Now they have presented the first fossil record of a group of water striders in copulation. Fossilized mating insects are an irreplaceable tool for understanding the evolution of mating behaviors and life history traits in the deep-time record of insects. A research group led by Prof. HUANG Diying from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences has systematically studied fossil water striders from the mid-Cretaceous of northern Myanmar (about 100 million years ago) in recent years. Now they have presented the first fossil record of a group of water striders in copulation. The findings were published in Proceedings of the Royal Society B on April 3. According to the researchers, instances of copulation are particularly rare in fossil insects, especially aquatic species, thus limiting our understanding of relevant behavioral strategies across geological time periods. Based on a comprehensive analysis of the functional morphology and behavioral ecology of the fossilized water striders, the researchers revealed the mating behavior and potential sexual conflicts of Cretaceous water striders. Gerromorpha includes water striders and their relatives that are conspicuously adapted to motion, feeding, and mating on the water surface. They occupy a wide range of niches including freshwater, coastal, and even pelagic environments. The specialized morphology and diverse behavior of gerromorphans have become hot research topics in evolutionary biology, ecology, and even interdisciplinary studies, and have provided a theoretical basis for the development of biomimetic technology on water surfaces. The common gerromorphan mating system is characterized by strong sexual conflict, manifested as copulatory struggles between the sexes, along with a range of male behaviors such as harassment, coercive violation, and intimidation, while females resist costly mating attempts. The fossil record of gerromorphan insects is limited. For example, only one Mesozoic example of Gerridae has been found in French amber. In the specimen reported in this study, seven adults of Burmogerris rarus gen. et sp. nov., comprising three paired individuals and a single adult male, as well as four recognizable water strider nymphs are enclosed in an amber piece. Of these, two pairs were captured in mating situations, with smaller males riding on the backs of the females. In addition, two pairs and a single male appear to have been preserved in the same layer near the upper surface of the amber. “We speculate that the small-sized male B. rarus is unlikely to be territorial, while this species maintains a high population density in the Myanmar amber forest,” said Dr. FU Yanzhe from the research group. Morphological studies using confocal laser microscopy and fluorescence microscopy revealed sexual dimorphism in the protibiae of the new fossils: specifically, protibiae are slightly curved in males while they are straight in females. In addition, male protibiae have 15–17 discontinuous clusters of pegs along the innermost edge, forming a comb-like structure that is absent in females. “By comparing the male’s protibial combs with species in the related family Veliidae, we suggest that the specialized protibial comb of the new fossils functions as a grasping apparatus, likely representing an adaptation to overcome female resistance during struggles,” said Prof. HUANG. These paired fossils probably represent a stage of precopulatory struggle or postcopulatory contact guarding. Males used such contact guarding to prolong mating and thus avoid sperm competition. Since guarding could lead to prolonged association between males and females, the probability of being trapped by resin during mating increased. The researchers suggested that B. rarus males were more likely to actively search for females rather than adopt a sit-and-wait strategy. The new discovery in Myanmar amber has significant implications for understanding the early evolution of mating behavior in water striders. Drawing from insights into the paleoecology of the Myanmar amber biota and an analysis of the morphology, including body size, wings, legs, and claws, of the new fossils, this study suggests that B. rarus most likely inhabited small, slow-flowing water bodies, such as tidal pools, near the coast in the Burmese amber forest窗体顶端. The paired water striders Burmogerris rarus, from Myanmar amber
Photomicrographs of Burmogerris rarus
Ecological reconstruction
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Cestoda, commonly known as tapeworms, is a large class of the platyhelminth phylum with about 5000 species described to date. Recently, LUO Cihang, a PhD candidate, supervised by Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS), collaborated with other scientists from Yunnan University, and Germany, UK, , Myanmar, reported an enigmatic fossil from mid-Cretaceous Kachin amber (about 100 million years ago), on Geology on March 22, 2024. Cestoda, commonly known as tapeworms, is a large class of the platyhelminth phylum with about 5000 species described to date. Recently, LUO Cihang, a PhD candidate, supervised by Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS), collaborated with other scientists from Yunnan University, and Germany, UK, , Myanmar, reported an enigmatic fossil from mid-Cretaceous Kachin amber (about 100 million years ago), on Geology on March 22, 2024. This study thus probably provides not only the first partial body fossil of a tapeworm, but also arguably the most convincing body fossil of a flatworm, providing new evidence for the early evolution of tapeworm. Cestoda infect all major groups of vertebrate animals including humans and livestock, and can be found in almost all marine, freshwater, and terrestrial ecosystems. Their size is variable, ranging from less than 1 millimetre to more than 30 meters in length. Tapeworms are usually characterized by adults with a scolex (grasping head), a short neck, and a segmented body formed of multiple sets of genital organs (proglottids). Their scolex typically has hooks, suckers, or hooked tentacles, which can help them clung to the alimentary tract of their hosts. Most tapeworms have an obligatory parasitic life cycle involving two or three hosts. They have no mouth and digestive tract, and absorb nutrients directly from the gut of their hosts. The Order Trypanorhyncha is the most speciose tapeworm group in the marine realm, and it comprises one of the most ubiquitous and readily recognized parasites of marine fish. Trypanorhynch tapeworms are characterized by a scolex bearing 2 or 4 bothria, and a unique tentacular apparatus with four evaginable tentacles adorned with hooks as extensions of tentacle sheaths inside the scolex. Their larvae infect a wide variety of marine invertebrates (like crustaceans), as well as teleosts, and their adults are found in the stomach and intestine of sharks and rays. Molecular clock analyses calibrated by means of host fossil data estimate that trypanorhynch tapeworms had probably originated around the Triassic/Jurassic boundary (about 200 million years old), but their own fossils have never been found. In summary, the fossil records of tapeworms are extremely sparse due to their soft tissue and endoparasitic habitats, which greatly hampers our understanding of their early evolution. This fossil displays unique external (armature pattern) and internal (partially invaginated tentacle and rootless hooks) features which are most consistent with the tentacles of extant trypanorhynch tapeworms that parasitize marine elasmobranchs (mainly sharks and rays). Remarkably, nearly all extant trypanorhynchs are endoparasites of marine elasmobranchs, thus our study provides an exceptional example of a marine endoparasite trapped in amber, and sheds new lights on the taphonomy of amber. WANG says, “we reported the first body fossil of a tapeworm.” Tapeworms are thought to originate from the mid-Paleozoic based on their molecular framework, but their fossil record is extremely scarce due to their endoparasitic lifestyle. Although supposed tapeworm eggs were reported from a Carboniferous shark coprolite, the only widely accepted fossil record before the Quaternary is restricted to eggs discovered in a shark coprolite from the Permian, suggesting that the relationship between tapeworms and elasmobranch vertebrates was established at least by then. Although a tapeworm embryo was reported inside an egg, but it is putative due to the lack of confirmed characters. The new fossil is most consistent with the tentacle anatomy of a trypanorhynch tapeworm including the hook morphology, and thus represents the first body fossil of a tapeworm from the geological past. The new fossil presented the most convincing body fossil of a platyhelminth. Body fossils of the platyhelminth phylum are rare, with only a few examples. The oldest putative record comes from the Devonian of Latvia: circlets of hooks with sucker discs were found on placoderm and acanthodian fish. Although the arrangement of hooks is consistent with extant monogeneans, no other body structure was found. Two cysts that resemble trematode metacercariae were reported from mid-Cretaceous Kachin amber, however, no valid morphological details were given to support this. Lastly, the body fossil of Rhabdocoela discovered in Eocene Baltic amber has been plausibly reinterpreted as air bubbles. Therefore, this find represents the most convincing body fossil of a platyhelminth that has yet been found. The research indicated amber can preserve the internal structure of helminths. Using high resolution micro-CT, this study discovered that inside the fossil is a folded longitudinal structure appearing to run in a spiral around the longitudinal axis and it extends to the anteriormost part. This is in accordance with the invaginated tentacle of a trypanorhynch. Meanwhile, the rootless hooks are also the same as those of trypanorhynchs. Previous research has indicated that the internal structure can be preserved intact as in extant forms, but these studies are all focused on arthropods. “Our results highlight that amber can preserve the internal structure of helminths like tapeworms on geologic time scales”, says WANG. The research results provided a remarkable example of a marine endoparasite trapped in amber. Some gleicheniacean trichomes and one scale insect nymph are preserved together with the partial worm fossil in the same amber specimen, clearly indicating a terrestrial or onshore environment at the time of entrapment in resin. Moreover, there are many sand grains uniformly distributed inside the amber, implying that entrapment of the fossil occurred in a sandy environment. Furthermore, previous evidence shows that Kachin amber was deposited in a near-shore environment. Therefore, a possible scenario can be proposed: the elasmobranch host of the tapeworm was stranded by a tide or storm, for example. The trypanorhynch had an extruded tentacle in the dying host, and its host was bitten by a higher-level terrestrial predator or scavenger; when the host was ingested by the predator, the tentacle was pulled apart from the trunk, dislodged from the intestine and came stuck to some nearby resin. “Our study further supports the hypothesis that Kachin amber was probably deposited in a paralic paleoenvironment, and also highlights the importance of amber research in paleoparasitology”, add WANG. This research was supported by the National Natural Science Foundation of China, the Second Tibetan Plateau Scientific Expedition and Research, and the Deep-time Digital Earth (DDE) Big Science Program. Reference: Luo Cihang, Palm H.W., Zhuang Yuhui, Jarzembowski E.A., Nyunt T.T., Wang Bo, 2024. Exceptional preservation of a marine tapeworm tentacle in Cretaceous amber. Geology. https://doi.org/10.1130/G52071.1. The fossil tapeworm from mid-Cretaceous Kachin amber (~99 Ma; million years ago) and the comparison with the tentacle of an extant trypanorhynch tapeworm. (A) Microscopic image of fossil tapeworm. (B) Micro-CT image of fossil tapeworm. (C) Scanning electron microscopy image of an extant trypanorhynch tapeworm. The comparison of the internal structure of the fossil (A) with the tentacle of an extant trypanorhynch tapeworm (B). Abbreviation: ivt—invaginated tentacle. A hypothetical ecological reconstruction of the fossil trypanorhynch tapeworm (drawn by YANG Dinghua.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Recently, the Late Paleozoic research group from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), and researchers from Nanjing University confirmed the occurrence of high-temperature wildfire events and enhanced soil erosion associated with intense volcanism during the P–T transition based on the PAHs and Hg contents at the Dalongkou section in the northern mid-latitude Northwest China, which provides important evidence for understanding the evolution of terrestrial ecosystems during the P–T transition. The results were recently published on Palaeogeography, Palaeoclimatology, Palaeoecology. The Permian–Triassic (P–T) mass extinction was the most severe mass extinction event of the Phanerozoic and caused catastrophic changes in the marine and terrestrial ecosystems. This environmental deterioration has been triggered by emissions of massive greenhouse and poisonous gases from the Siberian Traps large igneous province and intensive large-scale continental arc volcanism. However, the response of terrestrial ecosystems in different regions to the P–T mass extinction remains unclear. Recently, the Late Paleozoic research group from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), and researchers from Nanjing University confirmed the occurrence of high-temperature wildfire events and enhanced soil erosion associated with intense volcanism during the P–T transition based on the PAHs and Hg contents at the Dalongkou section in the northern mid-latitude Northwest China, which provides important evidence for understanding the evolution of terrestrial ecosystems during the P–T transition. The results were recently published on Palaeogeography, Palaeoclimatology, Palaeoecology. This study leveraged a combined approach to report a multi-proxy geochemical study of combustion-related PAHs and Hg concentrations in sedimentary rock samples from the classic and well-studied P–T terrestrial Dalongkou section. PAH records re？ect an obvious vegetation changeover accompanied by frequent high-temperature combustion events and enhanced soil erosion, the Hg enrichments and organic carbon-isotope provide robust evidence for volcanic activities during the P–T transition. Prof. ZHANG Hua from NIGPAS says, “based on biostratigraphic distributions and charcoal abundance, we hypothesize that terrestrial ecosystems experienced substantial crises and changes owing to volcanism and frequent wildfire combustion events on land during the P–T transition.” Terrestrial responses were resolved in multiple intervals. These stages exhibit a close relationship between severe climatic conditions, wildfire combustion events, and floral changeover, reflecting a progressive trend toward a drier climate triggered by volcanic activities. ZHANG add, “consequently, we proposed that increased high-temperature combustion events under worse climatic conditions contributed to terrestrial vegetation change during the latest Permian.” This work was funded by the National Natural Science Foundation of China and the Strategic Priority Research Programs of the Chinese Academy of Sciences. Reference: Jiao, S. L., Zhang, H.*, Cai, Y. F., Jin, C. F., Shen, S. Z., 2024. Polycyclic aromatic hydrocarbons (PAHs) evidence for frequent combustion events on land during the Permian–Triassic transition in Northwest China. Palaeogeogr. Palaeoclimatol. Palaeoecol. https://doi.org/10.1016/j.palaeo.2024.112152.
Figure 1 GC-MS chromatograms and structures of PAHs from the Dalongkou section.
Figure 2 Stratigraphic variations organic carbon-isotope, Hg concentration, DBF concentration, ∑pyPAHs concentration, clumped isotope-derived paleotemperature records, charcoal abundance and reflectance, and spore-pollen in the Dalongkou section.
Figure 3 Conceptual reconstruction of environment changes in terrestrial–marine systems during the end-Permian mass extinction.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
A recent investigation of fossil plants reveals the plant–insect interactions across the Triassic–Jurassic boundary in the Sichuan Basin, South China. This study was completed by an international research team led by Prof. WANG Yongdong from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Science (NIGPAS), with collaboration with Prof. Stephen McLoughlin from the Swedish Museum of Natural History, and published in an international journal of Frontiers in Ecology and Evolution. A recent investigation of fossil plants reveals the plant–insect interactions across the Triassic–Jurassic boundary in the Sichuan Basin, South China. This study was completed by an international research team led by Prof. WANG Yongdong from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Science (NIGPAS), with collaboration with Prof. Stephen McLoughlin from the Swedish Museum of Natural History, and published in an international journal of Frontiers in Ecology and Evolution. Plants and insects are the most diverse and ecologically important organisms in the terrestrial biosphere. Their interactions are also among the richest biotic relationships, and offer significant insights into the evolution of terrestrial ecosystem complexity through the geological record. The fossil plants of the late Rhaetian Xujiahe Formation and the earliest Jurassic Zhenzhuchong Formation floral assemblages provides the first data on foliar herbivory generated by terrestrial arthropods across the Triassic–Jurassic transition in the eastern Tethys (East Asia) region. “The damage types from the two studied fossil assemblages are collectively attributed to seven functional feeding and egg-laying categories (i.e., hole feeding, margin feeding, surface feeding, skeletonization, piercing and sucking, oviposition, and galling)", says XU Yuanyuan from the research team. Most feeding strategies are spread across the major plant groups and persist through theTriassic–Jurassic boundary, with the exception of skeletonization (a category of external foliage feeding), which was restricted to the latest Triassic within dipteridacean ferns. The survey reveals that the respective frequency and diversity of interactions between plants and insects prior to and following the end-Triassic mass extinction event are almost the same, despite a substantial turnover of floral components. This suggests that insect herbivores were largely able to transfer to alternative (but commonly related) plant groups during the dramatic floristic turnover and environmental changes at the end of the Triassic. Sporadic occurrences of foliar modifications, such as marginal cusps on pinnules of Pterophyllum and prominent ridges on the rachises of some ferns and bennettites are interpreted as adaptations for defense against insect herbivores. XU says, “A few differences in taxonomic composition and herbivory representation between the latest Triassic Xujiahe flora and the earliest Jurassic Zhenzhuchong flora are more likely to be related to collection and preservational biases rather than reflecting palaeoecological changes”. This preliminary assessment of herbivory across the Triassic–Jurassic boundary requires complementary studies within the Sichuan Basin, South China, to verify the regional patterns of vegetation and herbivory change in the subtropics of East Asia, and also encourage equivalent investigations from other parts of the world to clarify the global patterns of plant–insect interactions and floristic change across this major event in Earth’s history. This study is financially supported by the National Natural Science Foundation of China, the Swedish Research Council and CSC. Reference: Yuanyuan Xu, Yongdong Wang*, Liqin Li, Ning Lu, Yanbin Zhu, Zhuanli Huang, & Stephen McLoughlin*, 2023. Plant-insect interactions across the Triassic–Jurassic boundary in the Sichuan Basin, South China. Frontiers in Ecology and Evolution, 11: 1338865. https://doi.org/10.3389/fevo.2023.1338865. Figure 1. Diversity of damage types among the various plant groups and the proportion of functional feeding groups represented within the uppermost Triassic and Lower Jurassic assemblages. Figure 2. Examples of various damage types on different plant groups from Member VII of the Xujiahe Formation. Figure 3. Examples of various damage types on different plant groups from the Bed 2 of the Zhenzhuchong Formation. Figure 4. Examples of physical defenses on some leaf fragments. (A, B) Showing prominent teeth on the apices of pinnules of Pterophyllum ctenoides. (C) Showing obvious thickening ridges (wrinkles) on the rachis of Pterophyllum ctenoides.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
On January 24, 2024, a research team led by Professor ZHU Maoyan from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NGIPAS), published their latest research finding of ~1.63-billion-year-old multicellular fossils from North China, on the prestigious journal Science Advances. On January 24, 2024, a research team led by Professor ZHU Maoyan from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NGIPAS), published their latest research finding of ~1.63-billion-year-old multicellular fossils from North China, on the prestigious journal Science Advances. These exquisitely preserved microfossils were considered as currently the oldest record of multicellular eukaryotes. The study is another breakthrough after their finding of decimeter-sized eukaryotic fossils in the Yanshan area, North China, and extends back the emergence of multicellularity in eukaryotes by about 70 million years. All complex life on Earth, including diverse animals, land plants, macroscopic fungi and seaweeds, are multicellular eukaryotes. Therefore, multicellularity is key for eukaryotes to acquire organismal complexity and large size, and often regarded as one major transition in Earth’s life history by scientists. However, it is still poorly understood when eukaryotes first evolved this innovation in their deep evolutionary history. Fossil records with convincing evidence show that eukaryotes with simple multicellularity already appeared at 1.05 billion years ago, including red and green algae, and putative fungi. Older records claimed to be multicellular eukaryotes, but most of them are controversial due to their simple morphology and lack of cellular structure. “The newly discovered multicellular fossils are from the late Paleoproterozoic Chuanlinggou Formation of ~1635 million year old. They are unbranched uniseriate filaments made up of two to more twenty large cylindrical or barrel-shaped cells, with diameter of 20-194 μm, and incomplete length up to 860 μm. These filaments show a certain degree of complexity based on their morphological variation”, says MIAO Lanyun from theresearch team. Filaments can be constant or tapering throughout the entire length, or only tapering at one end. Morphometric analyses demonstrate their morphological continuity which suggest they should represent a single biological species, instead of discrete species. They are named as Qingshania magnifica, 1989, a form taxon with similar morphology and size, and also described from the Chuanlinggou Formation. One particularly important feature of Qingshania, is the round intracellular structure (diameter 15-20 μm) in some cells. These structure are comparable to asexual spores known in many eukaryotic algae, indicating Qingshanialikely reproduced by spores. In modern life, uniseriate filaments widely occur in both prokaryotes (bacteria and archaea) and eukaryotes. The combination of large cell size, large range of filament diameter, morphological variation and intracellular spores, demonstrate the eukaryotic affinity of Qingshania, as no known prokaryotes can be such complex. Filamentous prokaryotes are commonly very small, about 1-3 μm in diameter, and distribute in more than 147 genera of 12 phyla. Some cyanobacteria and sulfur bacteria may reach large size up to 200 μm thick, but these large prokaryotes are very simple in morphology with disc-shaped cells and do not reproduce via spores. The best modern analogues are some green algae, although filaments also occur in other groups of eukaryotic algae (red algae, brown algae, yellow algae, charophytes, etc.), as well as fungi and oomycetes. MIAO add, “this indicates Qingshania was most likely photosynthetic algae, probably belonging to extinct stem group of Archaeplastids (a major group consisting of red algae, green algae and land plants, as well as Glaucophytes), although its exact affinity is still unclear.” In addition, they have conducted Raman spectroscopic investigation to test the eukaryotic affinity of Qingshania, from the perspective of chemical composition, and used 3 cyanobacterial taxa as comparison. Raman spectra revealed 2 broad peaks characteristic of disordered carbonaceous matter, and the estimated burial temperatures using Raman parameters range from 205 to 250 °C, indicating low degree of metamorphism. Principal component of analysis (PCA) of Raman spectra sorted Qingshania and cyanobacterial taxa into two distinct clusters , indicating Qingshania has different organic matter from those of cyanobacterial fossils, further supporting the eukaryotic affinity of Qingshania. At present, the oldest unambiguous eukaryotic fossils are unicellular forms from late Paleoproterozoic sediments (~1.65 billion years ago) in North China and Northern Australia. Qingshania appeared only slightly later than them, indicating eukaryotes acquired simple multicellularity very early in their evolutionary history. As eukaryotic algae (Archaeplastids) originated after the last eukaryotic common ancestor (LECA), the discovery of Qingshania further supports the early appearance of LECA in late Paleoproterozoic (which is consistent with many molecular clock studies), rather than at late Mesoproterozoic of about 1 billion years ago, if Qingshaniawas truly algal in nature. Professor Andrew Knoll from Harvard University and Professor QU Yuangaofrom the Institute of Deep-sea Science and Engineering, CAS, joint the study. This study was jointly funded by the National Key Research and Development Program of China, the National Natural Science Foundation of China and the Innovation Cross-Team of the CAS. References:Miao, L., Yin, Z., Knoll, A.H., Qu, Y., Zhu, M.*, 2024. 1.63-billion-year-old multicellular eukaryotes from the Chuanlinggou Formation in North China. Science Advances. https://www.science.org/doi/10.1126/sciadv.adk3208.
Multicellular fossil Qingshania from the Chuanlinggou Formation. Scale bar equals 100 μm for F-H and K, and 50 μm for the rest (Miao et al., 2024b). Multicellular fossil Qingshania with a round intracellular structure interpreted to be spore. Scale bar equals 50 μm for A, C, D and F (Miao et al., 2024b). Morphometric analyses of Qingshania (A-D), filament size frequency distribution (F), and comparison with modern large eukaryotic and prokaryotic filaments (A, B, E). Chaetomorpha and Urospora are green algae; Oscillatoriais a cyanobacterium; Beggiatoa and Thioploca are sulfur bacteria (Miao et al., 2024b). Raman analyses of Qingshania and 3 cyanobacterial taxa (Miao et al., 2024b). Principal component analysis (PCA) of Raman spectra of Qingshania and 3 cyanobacterial taxa (Miao et al., 2024b). Simplified eukaryotic tree (A) and representative early eukaryotic fossils (B). In eukaryotic tree, grey dash lines represent stem group eukaryotes. Solid lines denote crown group eukaryotes (LECA plus its descendants). Grey bars at nodes display the estimated age range of divergence of major branches from a molecular clock study (Parfrey et al., 2011, PNAS). Scale bar in the green algal fossil equals 500 μm; the rest are 50 μm (Miao et al., 2024b).
Contact: LIU Yun, Propagandist Email:yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Recently, Dr. JIANG Hui supervised by Professors WANG Bo and ZHANG Haichun from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), led a collaborative cicada study with scholars from several countries. Their research aimed to clarify the early evolutionary history of Cicadoidea fossils, the phylogenetic relationships between Mesozoic fossils and extant Cicadoidea, the macroevolution of body structure adaptations, and their relationship with environmental changes. The related findings were recently published in Nature Communications. Recently, Dr. JIANG Hui supervised by Professors WANG Bo and ZHANG Haichun from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), led a collaborative cicada study with scholars from several countries. Their research aimed to clarify the early evolutionary history of Cicadoidea fossils, the phylogenetic relationships between Mesozoic fossils and extant Cicadoidea, the macroevolution of body structure adaptations, and their relationship with environmental changes. The related findings were recently published in Nature Communications. Cicada, here referring to the superfamily Cicadoidea, is well-known for its evolution of sound production system, exceptional long-term subterranean habits, and symbolic attributes and utility in research that widely exists in culture, life, and science. Extant Cicadoidea includes the globally widespread Cicadidae, commonly known as true/singing cicadas, and relictual Tettigarctidae, found only in Australia and colloquially known as hairy cicadas. Currently, the earliest fossil of Cicadoidea was found in the Triassic. All Mesozoic (approximately 252 to 66 million years ago) Cicadoidea fossils have traditionally been classified into Cicadidae and Tettigarctidae based on a few distinct and conservative morphological features. However, this direct assignment of Mesozoic fossils to modern taxa may overlook the role of unique and transitional features provided by fossils in tracking their early evolutionary paths. This study explores the phylogenetic relationships of fossil and extant Cicadoidea groups for the first time. It reveals that Mesozoic Cicadoidea fossils include stem cicadoids, stem tettigarctids, and stem cicadids. Some Mesozoic fossils previously classified as Tettigarctidae might actually be closer to modern Cicadidae phylogenetically. The clades of Cicadidae and Tettigarctidae might have diverged at or by the Middle Jurassic. Due to preservation issues, the classification of insect fossils often relies on the preserved partial morphological features. This study conducted a morphological analysis of the partial structures of adults and nymphs, such as wings, non-wing body parts, and nymphal legs, to compare subtle continuous morphological changes with classification and phylogenetic outcomes. The research found that specialized homologous structures in insect fossils might contain previously overlooked identifiable transitional variations. An in-depth examination of these continuous morphological changes can provide a more precise understanding of the impact of spatiotemporal changes on morphological evolution and further clarify patterns of macroevolution. For example, changes in the head and labium might reflect resistance adaptations due to feeding pressures from host plant changes. Additionally, changes in the thoracic notum, and alterations in wing venation and outline, may indicate the evolution of flight muscles and capabilities. Changes in the head and thorax can also be quantified and compared. Producing sounds is a vital communication method for many animals. Modern Cicadidae species can produce the loudest sounds among insects, reaching nearly 120 decibels via tymbal mechanisms. In contrast, Tettigarctidae communicate with subtler vibrational signals transmitted through the substrate, lacking the ability to produce loud sounds. The varied sound-producing mechanisms between Cicadidae and Tettigarctidae ignite curiosity about the initial evolution of their acoustic structures and behaviours. In this study, tymbals were identified in all Mesozoic cicadoid stem groups, preserved in both male and female specimens. This is the first identification of tymbal structures in Cicadoidea fossils, capturing this communication method in the fossil record. The majority of relatively intact fossils lacked elements for intricate sound production and auditory systems, suggesting mid-Cretaceous cicadoids may have relied on substrate-transmitted vibrations for communication, rather than producing or perceiving high-decibel songs. Additionally, there are instances where the discovery of tymbal muscles and an abdominal cavity in a fossil, alongside preserved tracheae, flight muscles, and Marplesian tubes, suggests the possibility of an inherent abdominal cavity and resonating abilities similar to those found in the abdomens of modern singing cicadas. Consequently, the study posits another hypothesis: certain mid-Cretaceous Cicadoidea groups may have generated sounds louder than substrate-transmitted vibrations. Anyway, compared to modern singing cicadas, the species of Cicadoidea might have been relatively silent for the majority periods of Mesozoic. This study also reports the oldest known Cicadoidea nymph and exuviae fossils from mid-Cretaceous Kachin amber. The prominently powerful fossorial forelegs of these nymphal fossils, akin to modern cicadas, suggest similar behaviours and robust capabilities for digging, soil transportation, and subterranean living. Cicada nymph and adult fossils show distinct ecological niches and survival strategies, with a notable shift from underground root feeding to above-ground stem feeding. Evidence of root feeding is infrequently found in fossils. However, cicada nymph fossils with specialized digging forelegs suggest this behaviour. This subterranean lifestyle presumably conferred a survival benefit, enabling extended underground habitation for cicada nymphs. This study also examines the occurrence of root feeding among arthropods in the fossil record. Given the adult and nymph Cicadoidea fossils from Kachin amber and the multitude of adult fossils from the Middle Jurassic Daohugou deposit, it's evident that mid-Mesozoic Cicadoidea demonstrated distinct life stage niches, facilitated biomass transfer from underground to above-ground, and influenced ecosystems in a manner akin to their modern cicadas. This work is jointly funded by the National Natural Science Foundation of China and the Chinese Academy of Sciences. Reference: Jiang Hui, Szwedo J., Labandeira C.C., Chen Jun, Moulds M.S., Mahler B., Muscente A.D., Zhuo De, Nyunt T.T., Zhang Haichun, Wei Cong, Rust J., Wang Bo (2024) Mesozoic evolution of cicadas and their origins of vocalization and root feeding. Nature Communications, 15: 376. https://doi.org/10.1038/s41467-023-44446-x. Adults, final instar nymph, and exuviae of Cicadoidea fossils in Kachin amber of Myanmar. Digital reconstructions from micro-CT data reveal a diverse array of morphologies throughout the evolution of Cicadoidea. Specialized fossorial forelegs of fossil and extant cicada nymphs. Phylogenetic and morphological analyses-based relative relationships discrimination and reconstruction. Life reconstruction of cicadas in the Mesozoic forest.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The research team revised the taxonomic characteristics of Xiajiajienia based on morphological features and discussed its potential taxonomic position within the Dicksoniaceae from a phylogenetic perspective. The results of this study have recently been published in the international peer-reviewed journal Cretaceous Research. The family Dicksoniaceae, one of the most important floristic elements of the Mesozoic, had two flourishing periods which is in the Middle Jurassic and the Early Cretaceous. Although there are still arguments about the classification of some taxa, fossil genera that yield cup-shaped or bivalvate indusia in sori have been considered members of the family Dicksoniaceae. Xiajiajienia Sun, Zheng, and Mei is a unique fossil taxon within the fern family Dicksoniaceae. It was originally described by Professor SUN Ge et al. on the basis of fossils discovered in Xiajiajie, Jilin and Huangbanjigou, Liaoning provinces, leading to the establishment of a new genus. In recent years there have been few reports on Xiajiajienia due to the lack of fossil specimens. Some of the sterile organs of the fossil specimens have been assigned to Cycadophyte, specifically as part of the genus Rehezamites by Pott, McLoughlin, Lindstrom, Wu and Friis. Led by Professor WANG Yongdong of the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), an international team recently conducted a systematic investigation on newly discovered material of the Xiajiajienia mirabila from the Jehol biota in wetsrn Liaoning Province. The research team revised the taxonomic characteristics of Xiajiajienia based on morphological features and discussed its potential taxonomic position within the Dicksoniaceae from a phylogenetic perspective. The results of this study have recently been published in the international peer-reviewed journal Cretaceous Research. The genus Xiajiajienia has marginal borne sori with bivalvate indusia in the fertile pinnule which were consistent with the diagnosis of Dicksoniaceae; but has unlobed drepaniform sterile pinnules, which were distinguishable from other genera in Dicksoniaceae. The newly found fossil specimen of Xiajiajienia was preserved as the impression with counterpart, and was collected from Huangbanjigou of Jianshangou Bed of the Jehol Biota, with fine preservation of delicate structures of sterile and fertile pinnules. The specimens provide the evidence of a "partially fertile pinna" that existed in Xiajiajienia. Fertile segments are slightly contracted and reduced. Sori are marginally borne, with distinct bivalvate indusia. Sterile pinnules are unlobed, drepaniform to long tongue-shaped, strongly decurrent. Based on the characteristics of the fertile pinnules, the research team discussed the phylogenetic position of Xiajiajienia using phylogenetic analysis methods combined with the constraints of the Molecular Scaffold of modern ferns and assessed its relationship to Dicksoniaceae, Dennstaedtiaceae, Lindsaeaceae, as well as other ferns with similar morphological characteristics of sorus. The results show that Xiajiajienia is more closely related to the Dicksoniaceae, and some fossil species of the genus Dicksonia L'Héritier than to the common Mesozoic fern Coniopteris Brongniart. In addition, based on the palaeoclimate reconstructions of the Jehol Biota in previous studies, the research team hypothesized that the growth environment preference of Xiajiajienia was a mild climate with seasonal variations, similar to that of certain modern Dicksonia species, with some regional moisture requirements. This work is jointly funded by the National Natural Science Foundation of China , the Strategic Priority Research Program (B) of the Chinese Academy of Sciences , the State Key Laboratory of Palaeobiology and Stratigraphy, the ICDP Integrated Understanding of the Early Jurassic Earth System and Timescale (JET) projects (IGCP 632, IGCP 655 and IGCP 739), and the China Scholarship Council. Reference: ZHANG, L., WANG, Y., RUHL, M., ZHU, Y. and LI, H. 2023. Re-investigations of the fossil fern Xiajiajienia mirabila (Dicksoniaceae) based on new material from the Lower Cretaceous of western Liaoning, China. Cretaceous Research, 149, 105543. https://doi.org/10.1016/j.cretres.2023.105543. Figure 1. Three types of pinnae of Xiajiajienia mirabila, partly fertile pinna (A-B), sterile pinna (C), and fertile pinna (D), all at a scale of 1 cm; subfigs. E, F, and G are partial enlargements of the sterile pinna of Figs. A, B, and C, respectively, showing their drepaniform and unlobed morphology, at scales of 2 mm, 2 mm, and 5 mm, respectively. Figure 2. Fertile pinnules and sori comparisons between Xiajiajienia mirabila and modern Dicksonia (D.lanata), showing characteristics of marginal borne sori with bivalvate indusia in the fertile pinnule. Figure 3. Sketch reconstructions of Xiajiajienia mirabila. A, the sterile pinna; B, the sterile pinnules; C, sorus, spore, and possible sporangium; D, fertile pinna (fully); and E, fertile pinna (partly). Figure 4. Majority-rule consensus tree of Xiajiajienia and its related groups by a cladistic analysis of reproductive structure characters.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Dany Azar, from the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences (NIGPAS) and the Lebanese University, has reported in Current Biology on December 4, 2023, which have found the earliest known fossil mosquito in Lower Cretaceous amber from Lebanon. What’s more, the well-preserved insects are two males of the same species with piercing mouthparts, suggesting they likely sucked blood. Dany Azar, from the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences (NIGPAS) and the Lebanese University, has reported in Current Biology on December 4, 2023, which have found the earliest known fossil mosquito in Lower Cretaceous amber from Lebanon. What’s more, the well-preserved insects are two males of the same species with piercing mouthparts, suggesting they likely sucked blood. “Lebanese amber is to date the oldest amber with intensive biological inclusions and it is a very important material as its formation is contemporaneous with the appearance and beginning of radiation of flowering plants, with all what follows of co-evolution between pollinators and flowering plants” said D. Azar. Among modern-day mosquitos, only females are hematophagous, meaning that they use piercing mouth parts to feed on the blood of people and other animals. “Molecular dating suggested that the family Culicidae arose during the Jurassic, but previously the oldest record was mid-Cretaceous,” said André Nel of the National Museum of Natural History of Paris (Muséum National d’Histoire Naturelle de Paris). “Here we have one from the early Cretaceous, about 30 million years before.” The Culicidae family of arthropods includes more than 3,000 species of mosquitoes. Female mosquitoes are notorious for their blood-feeding ways, which has made them a major vector for spreading infectious diseases. Hematophagy in insects is thought to have arisen as a shift from piercing-sucking mouthparts used to extract plant fluids. For example, blood-sucking fleas likely arose from nectar-feeding insects. But the evolution of blood-feeding has been hard to study in part due to gaps in the insect fossil record. In the new study, researchers describe two male mosquitos with piercing mouthparts, including an exceptionally sharp, triangular mandible and elongated structure with small, toothlike denticles. The new findings suggest that male mosquitoes in the past fed on blood as well, according to the researchers. They also help to narrow the “ghost-lineage gap” for mosquitoes, they say. They report that the mosquitos’ preservation in amber extends the definitive occurrence of the mosquito family of insects into the early Cretaceous. It also suggests the evolution of hematophagy was more complicated than had been suspected, with hematophagous males in the distant past. In future work, Nel says they want to learn more about the 'utility' of having hematophagy in Cretaceous male mosquitos. They’re also curious to explore “why this no longer exists,” he says. This work was supported by the National Natural Science Foundation of China.. Reference: Dany Azar, Andre Nel, Diying Huang, Michael S. Engel, The earliest fossil mosquito, Current Biology (2023), https://doi.org/10.1016/j.cub.2023.10.047. Dorsal view of male mosquito in amber. Detail of mouthparts using a confocal microscope; scale bar, 10 μm Age recovery of fossil mosquito in Lower Cretaceous amber from Lebanon
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
