Chitinozoans are organic-walled microfossils widely recorded in Ordovician to Devonian (about 400 million years ago) marine sediments and usually shaped like “bottles”, however, with a hitherto-unknown biologic affinity and used to be considered as metazoan eggs. Recently, researchers from China, Estonia and USA suggested that chitinozoans are more likely to be fossils of individual microorganisms rather than eggs. The results were published online on July 31, 2019 in Proceedings of the Royal Society B. Chitinozoans are organic-walled microfossils widely recorded in Ordovician to Devonian (about 400 million years ago) marine sediments and usually shaped like "bottles". Their biological affinity remains unknown, but most commonly, they are interpreted as eggs of marine metazoans. Recently, researchers from China, Estonia and USA suggested that chitinozoans are more likely to be fossils of individual microorganisms rather than eggs. The results were published online in Proceedings of the Royal Society B on July 31, 2019. Since their first description in the 1930s, multiple hypotheses have been put forward trying to explain their biological origin and ecology, including classification as protists, metazoans or egg capsules of metazoans. With the first report of some cocoon-like preservation in Desmochitina, chitinozoans have almost exclusively been interpreted as eggs of unknown marine metazoans, possibly some wormlike animals, during the last three decades. No further discussions related to their affinity have been advanced since then, even though the egg hypothesis makes no allowance for, nor does it explain, some of the morphological structures found in Chitinozoa. However, in a recent study conducted by Dr. LIANG Yan from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) and her collaborators, the researchers re-evaluated the egg hypothesis from the perspective of morphological variation of chitinozoans. They conducted a detailed case study focusing on single highly variable species Hercochitina violana sp. nov. in order to allow for a more quantitative analysis. The scientists compiled a dataset of measurements of 378 randomly selected species representing all 57 chitinozoan genera currently known, as well as a dataset of coefficients of variation (CV) in eggs from 45 extant aquatic metazoan species. For the first time, this allowed a reliable comparison of the magnitude of size variation between chitinozoans and undisputed eggs to further assess their possible analogy. The results showed that the range of variation in most chitinozoans was much larger than that of eggs of extant marine invertebrates or the hitherto reported undisputed fossil eggs. The range and type of size variation shown in Hercochitina violana sp. nov. potentially indicated an ontogenetic series rather than an intraspecific variation. Additionally, there is no analogue in extant metazoan eggs which have such complicated and delicate structures as developed in chitinozoans, not to mention the rapid evolutionary trend of ornamentations, which is also inconsistent with the prevailing egg hypothesis. It is more plausible to argue that most chitinozoans, with the exception of the unique Desmochitina, represent independent organic-walled microorganisms rather than eggs of metazoans. Reference: Liang Y*, Bernardo J, Goldman D, Nolvak J, Tang P, Wang W, Hints O*. 2019 Morphological variation suggests that chitinozoans may be fossils of individual microorganisms rather than metazoan eggs. Proc. R. Soc. B 20191270.
SEM images of Hercochitina violana sp. nov. showing the morphologic variation. (Image by NIGPAS)
The climate on the earth has gradually warmed up since the last glacial maximum some 20,000 years ago. Appropriate climate conditions have contributed to the formation and development of the Holocene farming culture. The way of production and lifestyle for the ancient people gradually changed from the early collecting, fishing and hunting to the later settled production with farming agriculture. This change in production and lifestyle was closely related to the environment variations at that time, and had a great impact on the development of human civilization. Vegetation in southern China has undergone significant changes since the last glacial maximum. Given the limitations of data, we still lack a comprehensive understanding of the concrete changing process and its relationship with human farming life. In order to better understand the variations of vegetation with climate fluctuation since the last glacial maximum in southern China, as well as the impact of human activities on vegetation, a research team consisting of Prof. WANG Weiming, Dr. SHU Junwu and Dr. CHEN Wei from Nanjing Institute of Geology and Palaeontology of Chinese Academy of Sciences, and Dr. LI Chunhai from Nanjing Institute of Geography and Limnology of Chinese Academy of Sciences, has carried out pollen study for 20 drilling cores in some less researched areas. Finally, pollen data from 14 sites have been selected for the restoration of vegetation over the past 20,000 years. The research results have recently been published on the journal Chinese Science: Earth Sciences. The research team gave for the first time the vegetation zoning maps around 18 ka BP, 9 ka BP and 6 ka BP respectively, and the distribution characteristics of plants in each zone/subzone are described. The main results are as follows: 1) The variation of vegetation in southern China since about 20,000 years generally coincides with the changing process of global climate after the last glacial maximum. Temperate vegetation around 18 ka BP can extends southward to the present south subtropical subzone, reflecting that the nature of vegetation still retained some climatic characteristics of the previous glacial period, although the climate had begun to warm up at that time. 2) During the Holocene megathermal, the characteristics of vegetation in the study area are rather distinct, which indicates similar features around both 9 ka BP and 6 ka BP. This reflects the general trend of global warming at that time on the one hand, and the overall control of southeast monsoon and southwest monsoon in southern China on the other hand. It is speculated that the long-term strong monsoon climate since 9 ka may be the main reason for the dominant vegetation distribution at that time, and its gradual convergence with the present. 3) High-resolution palynological study shows that although some climatic events since the last glacial maximum have been documented in some stratigraphic profiles, they have limited impact on the overall nature of local vegetation. In addition to the global climate change, the vegetation in the study area is also affected by the evolution and development of monsoon climate. 4) Human activities are not clearly reflected in 9 ka BP and 6 ka BP vegetation maps, which indicates that early farming activities have little influence on the original vegetation. The impact of human activities on vegetation is generally earlier in the middle and lower reaches of the Yangtze River than in the other areas of southern China, and the impact is more distinct. 5) The rise of sea level during the Holocene megathermal might also affect the distribution of vegetation at that time. Large-scale transgressions were recorded in Lake Dongqian, Lake Baima and Lake Xianghu in the early Holocene. This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences and the National Natural Science Foundation of China. Reference: Wang W*, Li C, Shu J, Chen W. 2019. Changes of vegetation in southern China. Science China Earth Sciences, https://doi.org/10.1007/s11430-018-9364-9
Geographic location map of newly added boreholes and boreholes in documents. solid dots, Newly added boreholes; hollow dots, boreholes in documents
Vegetation zoning map in southern China. (a) Modern vegetation zoning map; (b) 18 ka BP vegetation zoning map; (c) 9 ka BP vegetation zoning map; (d) 6 ka BP vegetation zoning map Contact: Prof. Wang Weiming, Principal Investigator Email: wmwang@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
In recent years, a research team led by Prof. WANG Yongdong from the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences, and Dr. Tian Ning, an associate professor from Shenyang Normal University, carried out a comprehensive study on the Mesozoic wood fossils containing fungal mycelia with some update discoveries. Recently, two new reports from this team have been published on the journals Cretaceous Research and Acta Geologica Sinica (Chinese Edition). Structurally preserved petrified woods contain not only information of wood anatomy, but also plenty of physiological and ecological information, including trace fossils of insect boring, fungal hyphae and other micro-organisms. Study of these permineralized plants is helpful to reveal the ecological and co-evolutionary relationships among plants, insects, fungi and other organisms in geological past. Abundant and diverse Cretaceous wood fossils have been recorded in China. However, previous studies of petrified wood mainly focused on their anatomy and taxonomy, little work has been reported on the fungal remains and the interaction between the wood hosts and fungi. In recent years, a research team led by Prof. WANG Yongdong from the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences, and Dr. Tian Ning, an associate professor from Shenyang Normal University, carried out a comprehensive study on the Mesozoic wood fossils containing fungal mycelia with some update discoveries. Recently, two new reports from this team have been published on the journals Cretaceous Research and Acta Geologica Sinica (Chinese Edition)(cover story). Well-preserved fossil mycelium consisting of clamp-bearing septate hyphae is found in a petrified conifer wood (Cupressinoxylon baomiqiaoense Zheng et Zhang) from the Lower Cretaceous Yunshan Formation in Heilongjiang Province, NE China. The fungal hyphae are tubular in shape with septa and typical clamp-connections. Taxonomically, the occurrence of clamp-connections indicates that the present fungal remains should be referred to the Basidiomycota. Ecologically, the present fossil mycelium is proposed to be a saprotroph, i.e. a wood rotting fungus. The decomposition of the tracheary middle lamina of the wood host strongly implies that the present fungal mycelium to be a white-rotting fungus. Additionally, similar basidiomyceous fossils with white rot function were found in fossil conifer wood of Agathoxylon sp. from the Lower Cretaceous Guantou Formation in Xinchang of Zhejiang Province, SE China. The present new finding of basidiomyceous fossils represents the first unequivocal records of Cretaceous wood-rotting fungi, provides increasing data on the fossil diversity of fungi in China, and contributes to further understanding the plant-fungal interaction in the Cretaceous terrestrial ecosystem. Reference: Tian Ning*, Wang Yongdong*, Zheng Shaolin, Zhu Zhipeng, 2019. White-rotting fungus with clamp-connections in a coniferous wood from the Cretaceous of Heilongjiang Province, NE China. Cretaceous Research, doi.org/10.1016/j.cretres.2018.11.011 (*authors for correspondence) Zhu Zhipeng, Li Fengshuo, Xie Aowei, Tian Ning, Wang Yongdong, 2018. New record of Early Cretaceous petrified wood with fungal infection in Xinchang of Zhejiang Province, Acta Geologica Sinica-Chinese Edition, 92: 1149-1162 (cover story). Fungal hyphae from the Early Cretaceous petrified wood in Heilongjiang Province, NE China (Image by TIAN Ning) Fungal hyphae from the Early Cretaceous petrified wood in Heilongjiang Province, NE China (Image by TIAN Ning) Fungal hyphae from the Early Cretaceous petrified wood in Zhejiang Province, SE China (Image by ZHU Zhipeng) Contact: Prof. WANG Yongdong, Principal Investigator Email: ydwang@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
What exactly controlled the Cambrian Explosion has been a subject of scientific debate since Darwin’s time. Recently, a joint China-UK-Russia research team gives strong support to the hypothesis that the oxygen content of the atmosphere and ocean was the principal controlling factor in early animal evolution. Early Cambrian sections of the Lena River in Siberia (Image by ZHU Maoyan) The Cambrian Explosion around 540 million years ago was a key event in the evolutionary history of life. But what exactly controlled the Cambrian Explosion has been a subject of scientific debate since Darwin’s time. A multidisciplinary study, published on May 6 in Nature Geoscience by a joint China-UK-Russia research team, gives strong support to the hypothesis that the oxygen content of the atmosphere and ocean was the principal controlling factor in early animal evolution. In past decades, important fossil discoveries revealed a puzzling pattern of episodic radiations and extinctions in early animal evolution. This pattern coincides with dramatic fluctuations in the carbon isotopic composition of seawater, according to study co-author ZHU Maoyan from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences. Lower Cambrian strata along the Aldan and Lena rivers in Siberia consist of continuous sequences of limestone with abundant fossils and reliable age constraints, making these rocks ideal for analysing ancient seawater chemistry. The isotopic signatures of the rocks correlate with the global production of oxygen, allowing the team to determine oxygen levels in shallow sea water and the atmosphere during the Cambrian Period. The study is the first to show that the pattern of episodic radiations and extinctions in early animal evolution closely matches extreme changes in atmospheric and oceanic oxygen levels. This result strongly suggests that oxygen played a fundamental role in the Cambrian Explosion of animals. “The complex creatures that came about during the Cambrian Explosion were the precursors to many of the modern animals we see today. By analysing carbon and sulphur isotopes found in ancient rocks, we are able to trace oxygen variations in Earth’s atmosphere and shallow oceans during the Cambrian Explosion. We found that evolutionary radiations follow a pattern of ‘boom and bust’ in tandem with the oxygen levels,” said Dr. HE Tianchen, study lead author and postdoctoral researcher at the University of Leeds. According to Prof. Graham Shields, study co-author from UCL Earth Sciences, this is the first study to show clearly that our earliest animal ancestors experienced a series of evolutionary radiations and bottlenecks caused by extreme changes in atmospheric oxygen levels. The result was a veritable explosion of new animal forms during more than 13 million years of the Cambrian Period. Study co-author Dr. Benjamin Mills, from the School of Earth and Environment at Leeds, said, “The Siberian Platform gives us a unique window into early marine ecosystems. This area contains over half of all currently known fossilised diversity from the Cambrian Explosion.” “This has been an incredibly successful and exciting joint study. The question of the Cambrian Explosion trigger has puzzled scientists for years. Now, the results give us convincing evidence to link the rapid appearance of animals as well as mass extinction during the early Cambrian with oxygen,” said co-author Andrey Yu Zhuravlev from Lomonosov Moscow State University. Study co-author YANG Aihua from Nanjing University said, "In the last decade, progress has been made in the Cambrian Explosion; this study shows the interactions between the biodiversity of animal and environment during the early Cambrian." Contact CHEN Xiaozheng Nanjing Institute of Geology and Palaeontology E-mail: chxzh@nigpas.ac.cn DOI: https://doi.org/10.1038/s41561-019-0357-z
Prof. LI Chunxiang from Nanjing Institute of Geology and Palaeontology of Chinese Academy of Sciences and her colleagues analyzed the combined data of morphology and molecular data available to re-evaluate the systematic position of Coniopteris. The researchers therefore propose that Coniopteris may be more closely related with Polypodiales than with Dicksoniaceae, and Coniopteris is probably a stem group of Polypodiales. This interpretation is consistent with the vertical annuli of Coniopteris, an apparent synapomorphy of Polypodiales.It is generally recognized that the fossil records are incomplete in nature, yet fossils had very important impact on our development of evolutionary theory. The value of a particular fossil in contributing to our knowledge in evolutionary history for any lineage depends upon an adequate description of sufficient characters including synapomorphies, necessary for the accurate identification of its affinities or precise phylogenetic placement. Here is a case of such kind of study. The extinct fern genus Coniopteris was a typical component in the Mesozoic flora with a wide distribution in both Northern and Southern Hemispheres from Early Jurassic to Early Cretaceous, and it played a very important role in stratigraphic correlation, while its character evolution and systematic position have both been unsolved mysteries.Prof. LI Chunxiang from Nanjing Institute of Geology and Palaeontology of Chinese Academy of Sciences and her colleagues analyzed the combined data of morphology and molecular data available to re-evaluate the systematic position of Coniopteris.The study produced the results as: (1) all extant genera in Dicksoniaceae have bivalvate indusia, while most species of Coniopteris have cup-shaped indusia; (2) most Dicksoniaceae occur in the tropical zone, different from the temperate habitats for most Coniopteris species; (3) Coniopteris may be herbaceous, whereas extant Dicksoniaceae are mostly tree-like ferns; and (4) Dicksoniaceae and Thyrsopteridaceae all have oblique annuli, while most species of Coniopteris have vertical ones.Based on these differences, Coniopteris should not be treated in Dicksoniaceae. Its systematic position was further evaluated by a cladistic analysis using morphological characters of spore-producing organs and spores and integrated with studies of fern molecular phylogeny as a constraint (molecular backbone). The results show that Coniopteris is clustered with Dennstaedtia, Lindsaea, and Odontosoria, not with Calochlaena, Dicksonia, and Lophosoria in Dicksoniaceae.The researchers therefore propose that Coniopteris may be more closely related with Polypodiales than with Dicksoniaceae, and Coniopteris is probably a stem group of Polypodiales. This interpretation is consistent with the vertical annuli of Coniopteris, an apparent synapomorphy of Polypodiales.The research was supported by Project from Shanghai Landscaping & City Appearance Administrative Bureau (Grant No. G162422), Projects of State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of geology and Palaeontology, CAS) (Grant No. Y626040108), and Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB26000000). Reference: Chunxiang Li, Xinyuan Miao, Li-Bing Zhang, Junye Ma, Jiasheng Hao (2019). Re-evaluation of the systematic position of the Jurassic–Early Cretaceous fern genus Coniopteris. https://doi.org/10.1016/j.cretres.2019.04.007 Sori of Coniopteris (G) and related species of Dennstaedtia (A-D) and Calochlaena straminea (F). Image by LI Chunxiang.. Majority-rule consensus tree of Coniopteris and its related extant groups corresponding to cladistic analysis based on reproductive structure characters and a molecular phylogenetic tree for the extant taxa as constraints. Sporangia types among the main clades are indicated on the right side of the tree (note: annuli are in illustrated). Image plotted by LI Chunxiang. Contact: Prof. LI Chunxiang, Principal Investigator Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Abundant Triassic radiolarian fossils were obtained from varicolored bedded cherts exposed in the Buruocang section near Jinlu village, Zedong, southern Tibet. The radiolarian‐bearing rocks represent fragmented remnants of the Neotethys oceanic sediments belonging to the mélange complex of the east part of the Yarlung‐Tsangpo Suture Zone. Two new middle Late Anisian radiolarian assemblages recognized from this section named Oertlispongus inaequispinosus and Triassocampe deweveri, respectively, are compared with those known from Europe, Far East Russia, Japan, and Turkey. These Anisian radiolarian fossils are the first reported in southern Tibet and the oldest radiolarian record within the Yarlung‐Tsangpo Suture Zone. They improve time constraints for the evolution of Neotethys in southern Tibet. In recent years, abundant Triassic-Cretaceous radiolarian fossils have been collected within the Yarlung Zangbo Suture Zone (YTSZ) in Zedong area of southern Tibet by the research group of Prof. LUO Hui from the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences. PhD candidate CHEN Dishu and others from Prof. Luo’s research group, in cooperation with Prof. Atsushi Matsuoka of Niigata University in Japan, documented an Anisian radiolarian fuana obtained from varicolored bedded cherts exposed in the Buruocang section near Jinlu village in Zedong recently. The radiolarian-bearing rocks represent fragmented remnants of the Neotethys oceanic sediments belonging to the mélange complex of the east part of the Yarlung-Tsangpo Suture Zone. Two new middle Late Anisian radiolarian assemblages recognized from this section named Oertlispongus inaequispinosus and Triassocampe deweveri, respectively, are compared with those known from Europe, Far East Russia, Japan, and Turkey. These Anisian radiolarian fossils are the first reported in southern Tibet and the oldest radiolarian record within the Yarlung-Tsangpo Suture Zone so far. They provide a valuable new age constraint and allow the researchers to infer the timing of the early stage of the Neotethyan evolution in southern Tibet. At least in the Anisian, the eastern YTSZ had a pelagic sedimentary environment. This research was supported by the Strategic Priority Research Program (B) of the Chinese Academy of Sciences, National Natural Science Foundation of China and also in part by the Japan Society for the Promotion of Science KAKENHI. Reference: Chen D, Luo H, Wang X, Xu B, Matsuoka A. Late Anisian radiolarian assemblages from the Yarlung-Tsangpo Suture Zone in the Jinlu area, Zedong, southern Tibet: Implications for the evolution of Neotethys. Island Arc. 2019: 1–10. https://doi.org/10.1111/iar.12302 Outcrop photographs of Buruocang section of the bedded cherts, in Zedong , southern Tibet, Image by CHEN Dishu. Correlation of Triassic radiolarian zones and subzones, Image plotted by CHEN Dishu. Late Anisian radiolarians from Sample 14BRC-11 at the Buruocang section, Image by CHEN Dishu. Contact: Prof. LUO Hui PhD Corresponding author Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Recently, the famous international geological journal Palaeogeography, Palaeoclimatology, Palaeoecology (commonly referred to as "Palaeo 3") published a new special issue on the topic of Mesozoic and Cenozoic evolution of eastern Tethys co-edited by Prof Li Jianguo and Prof. Sha Jingeng in the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, and their international cooperation team (volume 515, 2019). Since the 1960s when the theory of plate tectonics became established, the Tethys region has attracted the attention of many geologists because it has experienced a complex evolution involving numerous continental fragments drifting in several stages from the Gondwanan margin in the Southern Hemisphere northward to amalgamate with Eurasia in the Northern Hemisphere. This process and the subsequent orogenies caused great changes to the regional or even global topography and environments, which researchers now realize had important impact on climate and biotas. The vast literature on the evolution of the Tethys Ocean highlights several critical scientific issues that require further investigation. These include especially: (1) what was the extent of the Tethys and its surrounding landmasses at the time that Pangea began to break up?; (2) when and how did the Cimmeride terranes rift from Gondwana and collide with proto-Eurasia?; (3) what was the motion history of the Indian plate during its northward journey, and when and where did it collide with Eurasia?; (4) when did the Neo-Tethys come into being and subsequently close up?; (5) what was the driving force behind continental fragmentation that gave rise to the Neo-Tethys?; (6) what processes were involved in the uplift of the Qinghai-Xizang Plateau, and what was the chronology of uplift events?; (7) what were the impacts of these events on Earth’s climate and biotas? (Fig. 1). The answers to each question in above are complex and require a large number of facts or data from multiple regions and disciplines. So far, the data and findings revealed and accumulated by scientists are still very scarce, restricting our progress in the study of Tethys tectonics and biological evolution. The newly published special issue reports the latest research results of scientists from multiple countries in magmatic petrology, geochemistry, palaeontology and sedimentology from the eastern Tethys. A total of 13 research papers and one reviewing paper as preface are contained. These papers cover a multitude of issues relating to the evolution of the Tethys, such as the timing of initiation of the Neo-Tethys, the properties of the Bangong-Nujiang Tethys, the rifting process of the Indian plate, palaeoenvironmental events during Tethyan evolution, the impact on terrestrial ecosystems of closure of the Tethys and uplift of the Qinghai-Xizang Plateau. These advances provide insights into and will stimulate further research on the evolution of the eastern Tethys. This SI is a joint product of years of collaboration and efforts by scientists from various countries and is supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB03010103, XDB26000000 and XDA20070202), the National Natural Science Foundation of China (41872004), and UNESCO -IUGS project IGCP 632. Special issue information: Li, Jianguo, Sha, Jingeng, McLoughlin, Stephen, Wang, Xiaoming, eds., 2019. Palaeogeographic, palaeoclimatic and palaeoecologic evolution of eastern Tethys during the Mesozoic and Cenozoic. Palaeogeography, Palaeoclimatology, Palaeoecology 515. A summary of key events in the evolution of Tethys as studied by previous researchers and authors in this issue
Our understanding of the early evolutionary history of sponges is largely impeded by the scarcity of early sponge fossil record, In spite of the purported sponge fossil from the Ediacaran Weng’an Biota, the earliest sponge spicules were found in the Protohertzina anabarica zone of about 535 Ma old. However, the taxonomically informative sponge fossils, which should preserve articulated skeletal frames, were only known from the shale Lagerstatten started from the terminal Cambrian Stage 2. Examples include the black shale of the Niutitang and Hetang Formations, the Chengjiang Biota, the Sirius Passet Biota, the Kaili Biota, the Burgess Shale, etc..A recent study of Dr. LUO Cui from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and Prof. Dr. Joachim REITNER from the University of Goettingen, published online on Feb 28, 2019 in PalZ, revealed in situ, three-dimensionally preserved sponge fossils from the Terreneuvian phosphorites from Hunan, China.These phosphorites underlying the Ni-Mo layer of the Niutitang Formation is inferred to be no younger than the Cambrian Age 2 based on the previous radiometric dating and biostratigraphic studies of correlative strata. In situ preserved sponge fossils are distributed as nodular bodies in the authigenic carbonaceous cherty phosphorites which exhibit laminated and clotted cryptocrystalline fabrics. Some of the fossils are completely embedded in the honey-colored cryptocrystalline phosphates, while most of them are preserved in the way that the spicules are immediately encrusted by isopachous cryptocrystalline phosphate, with the remaining interspace filled by later phosphate or siliceous cements, and/or pyrobitumen.The morphology of two fossils was described as examples:One of them, preserved in the former state mentioned above, is thick-walled, consisting of similar triaxons of three different size hierarchies. The small spicules in the 2nd and 3rd hierarchies are randomly distributed. The other one, preserved in the latter state mentioned above, was investigated using grinding tomography to reconstruct its 3D architecture in a 6mm×5mm×1mm space. This fossil is mainly composed of pentactins, few hexactins, diactins, and other forms. Some pentactins are distributed with the paratangential rays more or less parallel to the surface of the nodular body, a way similar to hypodermalia.Other spicules are generally irregularly arranged, but sometimes also exhibit a perpendicular arrangement with respect to contacting spicules and to other spicules in the 3D space. These morphological types were previously unknown from the lower-middle Cambrian shale Lagerstatten, although they appear to be in accordance with the hexactinellid stem groups hypothesized by some researchers (e.g. Mehl, 1996; Dohrmann et al., 2008).In addition, various forms of disarticulated sponge spicules were also observed in these lower Cambrian phosphorites, some of which showing demosponge-specific features or combined features of hexactinellids and demosponges, indicating still unexplored sponge biodiversity in this particular age and taphonomic window.This study was financially supported by the National Natural Science Foundation of China, the Chinese Academy of Sciences, the CAS Key Laboratory of Economic Stratigraphy and Palaeogeography (NIGPAS), and the German Excellence Initiative (Goettingen Courant Center).Reference: Luo, Cui, and Joachim Reitner*. 2019. Three-dimensionally preserved stem-group hexactinellid sponge fossils from lower Cambrian (Stage 2) phosphorites of China. PalZ. doi:10.1007/s12542-018-00441-y. Petrology of the nodular phosphorites and the preservation of sponge fossils. Projection of the 3D architecture of the spicules in a nodular body in a 2D surface.
Recent advances in Devonian palaeoecosystems and palaeoenvironments of South China have been published in a special issue of “Palaeobiodiversity and Palaeoenivronments”. The eight contributions in this volume cover different fossil groups, including tentaculitids, brachiopods, conodonts, tabulate corals, ostracods, and ammonoids, meant to advance the understanding of Devonian palaeoecosystems and palaeoenvironments of South China, with a special emphasis on interplay between different fossil groups and environments during this critical period of Earth history.The issue was co-edited by Drs. Wenkun Qie and Kun Liang from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and Dr. Peter Konigshof from the Senckenberg Forschungsinstitut und Naturmuseum Frankfurt.The Devonian (419.2–358.9 Ma) was a critical period for the evolution of life in both terrestrial and marine ecosystems. It witnessed the appearances of first forest and amphibian on land, the largest metazoan reef ecosystem in Earth history, and two greatest biocrisises of the Phanerozoic (the Frasnian-Famennian and Hangenberg mass extinctions).The colonization of land by vascular plants caused major changes with respect to processes in the geo-, hydro-, and atmosphere. Continental weathering became strongly influenced by chemical processes, and thereby causing changes in riverine nutrient flux, and atmosphere CO2 concentration dropped abruptly to near modern level, all of which exert major impacts on the marine ecosystem. As many as global events, characterized by eustatic sea-level changes, anoxic/hypoxic events, and/or biological extinction/turnovers took place during the Devonian, demonstrating complex interactions between the Earth’s biotic, climatic, and environmental systems. Understanding the different fossil groups and the evolution of Devonian marine ecosystem at global or regional scale would help to gain important insights for the interplay between life and environment in deep time. South China is the most important area for the study of the Devonian system in China, where all the stratotype sections for the Chinese regional stages were established in shallow water facies of this region. Following the Kwangsian Orogeny, a transgression occurred in central Guangxi during the Lochkovian, and each sequences in South China starts with some siliciclastic sediment overlying a discontinuity surface. With intensified rifting, major differentiation of lithofacies and biofacies took place in the Emsian and Givetian stages, and the deposition of extensive carbonate platform was separated by deep-water interplatform basins. As a result, there are numerous well-preserved Devonian stratigraphic successions recording a variety of lithofacies and biofacies in South China, providing excellent materials to investigate the biotic and environmental events and their possible causes and effects.This special issue includes 1 editorial and 8 scientific papers, details are as following:1. Qie, W. K., Liang, K., Konigshof, P. 2019. Devonian palaeoecosystems and palaeoenvironments of South China. Palaeobiodiversity and Palaeoenvironments. 99:1–5.2. Wei, F., Zong, R. & Gong, Y.M. (2019). Tentaculitids and their evolutionary significance in the Early Devonian Dashatian section, South China. Palaeobiodiversity and Palaeoenvironments, 99(1).3. Guo, W., Nie, T., & Sun, Y.L. (2019). New data on biostratigraphy of the lower Devonian “Spirifer” tonkinensis Brachiopod fauna in South China and adjacent region. Palaeobiodiversity and Palaeoenvironments, 99(1).4. Lu, J.F., Valenzuela-Ríos, J.I., Wang, C., Liao, J.-C. & Wang, Y. (2019). Emsian (Lower Devonian) conodonts from the Lufengshan section (Guangxi, South China). Palaeobiodiversity and Palaeoenvironments, 99(1). https://doi.org/10.1007/s12549-018-0325-4 5. Zhang, M. & Ma, X. (2019). Origination and diversification of Devonian ambocoelioid brachiopods in South China. Palaeobiodiversity and Palaeoenvironments. Palaeobiodiversity and Palaeoenvironments, 99(1). https://doi.org/10.1007/s12549-018-0333-4 6. Qiao, L. & Qie, W.K. (2019). Palaeobiogeographic dynamics of brachiopod faunas during the Frasnian-Famennian biotic crisis in South China. Palaeobiodiversity and Palaeoenvironments, 99(1). https://doi.org/10.1007/s12549-018-0336-17. Liang, K., Qie, W., Pan, L. & Yin, B. (2019). Morphometrics and palaeoecology of syringoporoid tabulate corals from the upper Famennian (Devonian) Etoucun Formation, Huilong, South China. Palaeobiodiversity and Palaeoenvironments, 99(1). https://doi.org/10.1007/s12549-018-0363-y8. Song, J.J. & Gong, Y.M. (2019). Ostracods from the Devonian-Carboniferous transition in Dushan of Guizhou, South China. Palaeobiodiversity and Palaeoenvironments, 99(1). https://doi.org/10.1007/s12549-018-0322-79. Zhang, M., Becker, R.T., Ma, X., Zhang, Y. & Zong, P. (2019). Hangenberg Black Shale with cymaclymeniid ammonoids in the terminal Devonian of South China. Palaeobiodiversity and Palaeoenvironments. Palaeobiodiversity and Palaeoenvironments, 99(1). https://doi.org/10.1007/s12549-018-0348-xThis special issue is partly supported by the Strategic Priority Research Program (B) of Chinese Academy of Sciences (XDB26000000) and NSFC grant (41772004).
