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To illustrate the impact of genetically modified (GM) Bt maize on the natural enemy communities in the Huang-Huai-Hai summer maize-growing region in China, the abundance of 7 common predator taxa (Geocoris pallidipennis Costa, Harmonia axyridis (Pallas), lacewings, Orius sauteri (Poppius), Propylea japonica (Thunberg), spiders, and Staphylinidae) was quantitatively evaluated by comparing Bt-Cry1Ab DBN9936 and Bt-Cry1Ab/Cry2Aj Ruifeng 125 events to their near non-Bt isolines during the growing season from 2016 to 2019. A total of 10,302, 19,793, 13,536, and 5,672 individuals were observed during 4 years, and the abundance of each taxa on Bt maize varied between sample dates among those arthropod taxa. Shannon–Wiener diversity index of predator communities from 7 taxa showed very similar temporal dynamics and principal response curve analyses to examine community-level effects showed no significant differences in predator abundance in Bt maize compared with non-Bt maize. We conclude that the 2 Bt maize hybrids did not adversely affect the predator community in the Huang-Huai-Hai summer maize-growing region of China. [ABSTRACT FROM AUTHOR]

Japanese spotted fever (JSF) is caused by Rickettsia japonica, mainly vectored by hard ticks. However, whether R. japonica can be transmitted by other arthropods remains unknown.Moreover, it is of interest to investigatewhether other Rickettsia species cause spotted fever in endemic areas. In this study, a survey of Rickettsia species was performed in hematophagous arthropods (mosquitoes, tabanids, and ticks) from endemic areas for JSF in Hubei Province, central China. The results showed that the diversity and prevalence of Rickettsia species in mosquitoes are low, suggesting that mosquitoes may not be the vector of zoonotic Rickettsia species. A novel Rickettsia species showed a high prevalence (16.31%, 23/141) in tabanids and was named "Candidatus Rickettsia tabanidii." It is closely related to Rickettsia from fleas and mosquitoes; however, its pathogenicity in humans needs further investigation. Five Rickettsia species were identified in ticks. Rickettsia japonica, the agent of JSF, was detected only in Haemaphysalis longicornis and Haemaphysalis hystricis, suggesting that they may be the major vectors of R. japonica. Notably, two novel species were identified in H. hystricis ticks, one belonging to the spotted fever group and the other potentially belonging to the ancestral group. The latter one named "Candidatus Rickettsia hubeiensis" may provide valuable insight into the evolutionary history of Rickettsia. [ABSTRACT FROM AUTHOR]

Background: The early Cambrian arthropod clade Megacheira, also referred to as great appendage arthropods, comprised a group of diminutive and elongated predators during the early Palaeozoic era, around 518 million years ago. In addition to those identified in the mid-Cambrian Burgess Shale biota, numerous species are documented in the renowned 518-million-year-old Chengjiang biota of South China. Notably, one species, Tanglangia longicaudata, has remained inadequately understood due to limited available material and technological constraints. In this study, we, for the first time, examined eight fossil specimens (six individuals) utilizing state-of-the-art μCT and computer-based 3D rendering techniques to unveil the hitherto hidden ventral and appendicular morphology of this species. Results: We have identified a set of slender endopodites gradually narrowing distally, along with a leaf-shaped exopodite adorned with fringed setae along its margins, and a small putative exite attached to the basipodite. Our techniques have further revealed the presence of four pairs of biramous appendages in the head, aligning with the recently reported six-segmented head in other early euarthropods. Additionally, we have discerned two peduncle elements for the great appendage. These findings underscore that, despite the morphological diversity observed in early euarthropods, there exists similarity in appendicular morphology across various groups. In addition, we critically examine the existing literature on this taxon, disentangling previous mislabelings, mentions, descriptions, and, most importantly, illustrations. Conclusions: The μCT-based investigation of fossil material of Tanglangia longicaudata, a distinctive early Cambrian euarthropod from the renowned Chengjiang biota, enhances our comprehensive understanding of the evolutionary morphology of the Megacheira. Its overall morphological features, including large cup-shaped eyes, raptorial great appendages, and a remarkably elongated telson, suggest its potential ecological role as a crepuscular predator and adept swimmer in turbid waters. [ABSTRACT FROM AUTHOR]

Pectocaris species are intermediate- to large-sized Cambrian bivalved arthropods. Previous studies have documented Pectocaris exclusively from the Cambrian Series 2 Stage 3 Chengjiang biota in Yu'anshan Formation, Chiungchussu Stage in SW China. In this study, we report Pectocaris paraspatiosa sp. nov., and three other previously known Pectocaris from the Xiazhuang section in Kunming, which belongs to the Hongjingshao Formation and is a later phase within Cambrian Stage 3 than the Yu'anshan Formation. The new species can be distinguished from its congeners by the sparsely arranged endopodal endites and the morphologies of the abdomen, telson, and telson processes. We interpret P. paraspatiosa sp. nov. as a filter-feeder and a powerful swimmer adapted to shallow, agitated environments. Comparison among the Pectocaris species reinforces previous views that niche differentiation had been established among the congeneric species based on morphological differentiation. Our study shows the comprehensive occurrences of Pectocaris species outside the Chengjiang biota for the first time. With a review of the shared fossil taxa of Chengjiang and Xiaoshiba biotas, we identify a strong biological connection between the Yu'anshan and Hongjingshao Formations. [ABSTRACT FROM AUTHOR]

Despite the importance of ontogenetic data on early diverging euarthropods to our understanding of the ecology and evolution of past life, the data are distinctly lacking, as reconstructing life histories of fossil animals is often challenging. Here we report the growth trajectory of frontal appendages of the apex predator Amplectobelua symbrachiata , one of the most common radiodont arthropods from the early Cambrian Chengjiang biota (c. 520 Ma) of China. Analysis of 432 specimens (9.1–137.1 mm length; 1.3–25.6 mm height) reveals that appendages grew isometrically, with an estimated maximum size of the whole animal of c. 90 cm. Individuals grew rapidly compared to extant arthropods, as assessed using the electronic length-frequency analysis (ELEFAN) approach. Therefore, we show that the Cambrian apex predator A. symbrachiata was an extremely fast-growing arthropod, with an unusual life history strategy that formed as part of the escalatory 'arms race' that shaped the Cambrian explosion over 500 Ma. [ABSTRACT FROM AUTHOR]

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. This investigation of the late Rhaetian Xujiahe and the earliest Jurassic Zhenzhuchong 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 two 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). Most feeding strategies are spread across the major plant groups and persist through the Triassic-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 suggest 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. 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. We encourage further investigations exploring the distribution of insect damage in fossil floras from other palaeolatitudinal zones and spanning other major extinction events to develop a better understanding of terrestrial ecosystem responses to major crises in Earth's history. [ABSTRACT FROM AUTHOR]

While transgenic Bacillus thuringiensis (Bt) maize provides pest resistance and a reduced application of chemical pesticides, a comprehensive environmental risk assessment is mandatory before its field release. This research determined the concentrations of Bt protein in plant tissue and in arthropods under field conditions in Gongzhuling City, northeastern China, to provide guidance for the selection of indicator species for non-target risk assessment studies. Bt maize expressing Cry1Ab/2Aj and non-transformed near-isoline were grown under identical environmental and agricultural conditions. Cry1Ab/2Aj was detected in plant tissues and arthropods collected from Bt maize plots during pre-flowering, flowering, and post-flowering. The expression of Cry1Ab/2Aj varied across growth stages and maize tissues, as well as in the collected arthropods at the three growth stages. Therefore, representative species should be chosen to cover the whole growing season and to represent different habitats and ecological functions. Dalbulus maidis (Hemiptera: Cicadellidae), Rhopalosiphum padi (Hemiptera: Aphididae), Heteronychus arator (Coleoptera: Scarabaeidae), and Somaticus angulatus (Coleoptera: Tenebrionidae) are suitable non-target herbivores. Propylea japonica (Coleoptera: Coccinellidae), Paederus fuscipes (Coleoptera: Staphylinidae), Chrysoperla nipponensis (Neuroptera: Chrysopidae), and spiders are suggested predators. Apis cerana and Apis mellifera ligustica (both Hymenoptera: Apidae) represent pollinators and Folsomia candida (Collembola: Isotomidae) decomposers. [ABSTRACT FROM AUTHOR]

Biodiversity is threatened by global changes, but related research has focused primarily on species or functional group diversity, neglecting their interaction networks. The latter are particularly sensitive to global changes and essential for biodiversity maintenance. Furthermore, multiple global change factors are typically examined separately, rather than in concert which is more realistic in nature.To explore the responses of arthropod networks to multiple global changes, we conducted a field experiment in temperate grassland in northeast China, in which nitrogen (N) deposition, drought, snowmelt timing and their interactions were manipulated. We constructed and assessed networks of arthropod functional groups, and explored their responses to changes in plant communities and the abiotic environments.Nitrogen addition decreased arthropod network complexity because increased foliar N and simplified plant community strengthened trophic chains along a single pathway, weakening the net effect of other pathways. However, experimental drought decreased network complexity by filtering out plant species and changing micro‐habitats. While delayed snowmelt significantly increased arthropod abundance only in early spring, its interaction with N addition or with drought had various impacts on arthropod functional groups. Our results suggest that the interaction of arthropod consumers with plant species richness and with plant nutrients finally reduced the robustness, connectedness and function of entire species/functional group networks in response to global change factors.In conclusion, species loss and increasing plant nutrient concentrations are key factors simplifying networks under multiple global changes, and such simplification is likely to be strengthened if coupled with changes in micro‐habitats. Our study highlighted that the effects of multiple global change factors should be studied in concert, even though they occur in different seasons, so that their effects on ecological networks can be perceived as a panorama. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The artiopodans, consisting of trilobites and their relatives, were a major euarthropod group in the Paleozoic. Since the first discovery of Naraoia from the Chengjiang fauna, a significant number of artiopodans have been subsequently found in China. Here we describe three new artiopodan species from the lower Cambrian Chengjiang fauna (Cambrian Series 2, Stage 3) at Malong, Yunnan, China. Zhugeia acuticaudata gen. et sp. nov. is defined by a semielliptical cephalon with long genal spines, nine overlapping thoracic tergites, and a pygidium with an elongated needle-like median spine. Its cephalic shield covers multiple anterior thoracic tergites. Tonglaiia bispinosa gen. et sp. nov. is defined by a suboval cephalon, seven thoracic tergites, and a micropygous pygidium with a pair of parallel posteriormost spines. Sidneyia malongensis sp. nov., a new occurrence of Sidneyia from South China, is defined by a crescent-shaped cephalon, eight imbricated tergites, and an abdomen consisting of two cylindrical segments and a tail fluke. The evolutionary affinities of these new taxa are reconstructed and discussed in a phylogenetic context. Phylogenetic analyses resolve Z. acuticaudata among the xandarellids and T. bispinosa gen. et sp. nov. as a trilobitomorph with an uncertain placement, The discovery of three new species improves the biodiversity of artiopodans from the Cambrian and the Chengjiang fauna. [ABSTRACT FROM AUTHOR]

Two new species, Samarangopus testudineus sp. nov. from Hunan, South China and S. rotundifolius sp. nov. from Zhejiang, East China, are described and illustrated. Samarangopus testudineus sp. nov. is characterized by unusual testudinal patterns on the dorsal side of the body and well-differentiated marginal protuberances on tergites. Samarangopus rotundifolius sp. nov. features large, round, leaf-shaped marginal protuberances and small, candle-like dorsal protuberances on tergites. Both of these species are compared to similar species in detail. In addition, Eurypauropus japonicus Hagino & Scheller, 1985 is newly recorded from China. [ABSTRACT FROM AUTHOR]

Insects are a valuable biological resource on Earth, known for their high biodiversity, ease of cultivation, and large populations. In China, the utilization of insects has a long history and has produced significant economic and social benefits. Insect products such as silkworms, silk, and bees are already familiar to the public and have continuously promoted the global economy. Recently, in some ethnic minority areas of China, insect industries have become the main source of fiscal revenue and an essential industrial support for rural revitalization. This has laid a strong foundation for research and development in the insect industry throughout China. It is urgent to utilize national resources to focus on strategic issues related to the high effective development of the insect industry. By gathering related resources for insect research, breakthroughs are expected in the discovery and development of innovative materials, drugs, and proteins based on insect resources. Such advancements will create significant value for human society. [ABSTRACT FROM AUTHOR]

We report the extraordinarily preserved euarthropod Sidneyia minor sp. nov. from the Cambrian Stage 3 Xiaoshiba Lagerstätte in Yunnan, South China. So far this is the earliest occurrence of the genus. As with other species of Sidneyia, the new taxon shares similar features such as a crescent-shaped head shield with paired lateral notches for stalked eyes, but more significantly and new, is the presence of three pairs of post-antennal appendages beneath the head shield identified by micro-CT methods. We conclude that Sidneyia is a sister group to other members of Vicissicaudata within the diverse radiation of Artiopoda. [ABSTRACT FROM AUTHOR]

Animals breaking away from the sea was a revolutionary event in the evolution of life. Arthropods were the earliest metazoans to move onto land, and although a few Silurian freshwater and/or terrestrial arthropods have been found so far, these records are all from Laurussia. Here, we describe a new freshwater arthropod, Maldybulakia saierensis sp. nov., from the western Junggar, northwest China. Evidence from co‐occurring spores and body fossils of plants is presented in support of a Silurian (Pridoli) age for this new Maldybulakia species, alongside palaeosalinity data in support of our interpretation of it having lived in a freshwater environment. The discovery of this species brings forward the earliest appearance of the Maldybulakia, previously known from the Devonian of Kazakhstan and eastern Australia, to the late Silurian. It is the oldest body fossil record of a putatively freshwater arthropod outside Laurussia, and greatly expands their palaeogeographical distribution. In the middle and late Silurian, the discovery of freshwater arthropods on multiple plates/terranes, as well as their morphological diversity during this period, suggests that arthropods had left the marine environment by the early Silurian or even earlier. [ABSTRACT FROM AUTHOR]

The ontogenetic sequence of an early Cambrian redlichiid trilobite Bathynotus kueichouensis is presented on the basis of numerous articulated specimens from Guizhou, China. The body regionalization of B. kueichouensis witnessed a wide variation in the morphology of trunk segments between different thoracic regions, referred to as the ‘thoracic region 1-4’. A greater size variation of these long pleural spines is recognized from the earlier meraspid degrees in a gradual appearance or disappearance until the holaspid period. The thoroughly inverse variation of these pleural spines in size and form is seen for the first time during the process of trilobite segment formation, which offers an opportunity to trace the evolutionary path of trilobite body structures, associated with their functional morphology and behavior. The ontogenetic strategy of B. kueichouensis is broadly similar to those of other redlichioid representatives where the full ontogenetic sequence exhibited a balanced rate in segment expression and liberation. Such a developmental mode may be the reason why most redlichiids possess a micropygous body patterning during ontogeny and provides insights into the controls of early arthropod developmental segmentation during evolutionary process. [ABSTRACT FROM AUTHOR]

Jingmenviruses are a group of viruses identified recently, in 2014, and currently classified by the International Committee on Taxonomy of Viruses as unclassified Flaviviridae. These viruses closely related to flaviviruses are unique due to the segmented nature of their genome. The prototype jingmenvirus, Jingmen tick virus (JMTV), was discovered in Rhipicephalus microplus ticks collected from China in 2010. Jingmenviruses genomes are composed of four to five segments, encoding for up to seven structural proteins and two non-structural proteins, both of which display strong similarities with flaviviral non-structural proteins (NS2B/NS3 and NS5). Jingmenviruses are currently separated into two phylogenetic clades. One clade includes tick- and vertebrate-associated jingmenviruses, which have been detected in ticks and mosquitoes, as well as in humans, cattle, monkeys, bats, rodents, sheep, and tortoises. In addition to these molecular and serological detections, over a hundred human patients tested positive for jingmenviruses after developing febrile illness and flu-like symptoms in China and Serbia. The second phylogenetic clade includes insect-associated jingmenvirus sequences, which have been detected in a wide range of insect species, as well as in crustaceans, plants, and fungi. In addition to being found in various types of hosts, jingmenviruses are endemic, as they have been detected in a wide range of environments, all over the world. Taken together, all of these elements show that jingmenviruses correspond exactly to the definition of emerging viruses at risk of causing a pandemic, since they are already endemic, have a close association with arthropods, are found in animals in close contact with humans, and have caused sporadic cases of febrile illness in multiple patients. Despite these arguments, the vast majority of published data is from metagenomics studies and many aspects of jingmenvirus replication remain to be elucidated, such as their tropism, cycle of transmission, structure, and mechanisms of replication and restriction or epidemiology. It is therefore crucial to prioritize jingmenvirus research in the years to come, to be prepared for their emergence as human or veterinary pathogens. [ABSTRACT FROM AUTHOR]

A new small euarthropod Astutuscaris bispinifer gen. et sp. nov. is described from the early Cambrian Stage 4 Guanshan Biota in Yunnan, China. This new euarthropod possesses a wide head shield, a pair of possible eyes, paired frontalmost appendages located antero-medially, 11 imbricated tergites most of which have backward-directed tergopleura ending in almost posteriorly oriented spines, and two well-marked wide spines. The affinity of Astutuscaris among euarthropods is uncertain because of the undefined nature of its frontalmost appendages, the incomplete head shield, the anterior trunk tergites, and the limbs. There are about 24 species of non-trilobite euarthropods reported from the Guanshan Biota to date, the documentation of this new taxon expands the biological diversity of euarthropods from this important biota in Yunnan, China. [ABSTRACT FROM AUTHOR]

Transgenic Bacillus thuringiensis (Bt) maize has broad prospects for application in China. Before commercialization, it is necessary to assess possible ecological impacts, including impacts on non-target arthropods (NTAs) in the field. In the present study, transgenic Bt maize expressing cry1Ab/2Aj and its corresponding non-transformed near isoline were planted under the same environmental and agricultural conditions, and arthropods in the field were collected during the three main growth stages of maize. In a one year trial, the results showed the composition of NTA communities in the transgenic and control maize fields were similar. There were no significant differences for community-level parameters of species richness (S), Shannon–Wiener diversity index (H′), evenness index (J) and Simpson's dominant concentration (C) between the two types of maize fields. Likewise, a Bray–Curtis dissimilarity and distance analysis showed that Cry1Ab/2Aj toxin exposure did not increase community dissimilarities between Bt and non-Bt maize plots and that the structure of the NTAs community was similar on the two maize varieties. Furthermore, planting of the transgenic cry1Ab/2Aj maize did not affect the density or composition of non-target decomposers, herbivores, predators, parasitoids and pollinator guilds. In summary, our results showed that planting of Bt maize producing Cry1Ab/Cry2Aj proteins do not adversely affect population dynamics and diversity of NTAs. [ABSTRACT FROM AUTHOR]

The rapid appearance of major animal groups and complex marine communities during the Cambrian explosion is recorded in large part in Burgess Shale-type lagerstätten. However, the restricted temporal and spatial distribution of known lagerstätten continues to hinder the formation of a comprehensive perspective on Cambrian evolutionary faunas. Here we describe the Linyi Lagerstätte (ca. 504 mya), a new Cambrian Miaolingian lagerstätte from the Zhangxia Formation in Shandong Province, North China. The Linyi Lagerstätte contains a variety of well-preserved soft-bodied fossils, among which the non-trilobite arthropods, particularly the mollisoniids and radiodonts, are the most important groups. The new assemblage is remarkable for its excellent preservation of arthropod limbs, eyes and guts, as well as for its close similarity in taxonomic composition to Laurentian lagerstätten. The distinctive Linyi Lagerstätte holds great promise for providing additional insights into the morphological disparity, community structure and paleogeographic range of marine faunas during the middle Cambrian (Miaolingian). [ABSTRACT FROM AUTHOR]

The mechanisms driving species co‐occurrence are varied and include biotic interactions, abiotic factors, and scale‐dependent processes. Based on a comprehensive dataset of lepidopteran herbivores recorded from a large‐scale forest biodiversity experiment, we tested the contribution to herbivore species co‐occurrence of herbivore phylogenetic relatedness, plant diversity and functional traits, and spatial scale. We found that Lepidoptera co‐occurrence was negatively associated with their phylogenetic relatedness, tree diversity, and defensive traits, but positively associated with nutritional functional traits. Furthermore, species co‐occurrence was higher at larger spatial scales (tree species or plot) than at smaller scale (individual trees). Our results provide evidence supporting both environmental filtering and competition exclusion hypotheses, and highlight the significance of functionality in shaping species coexistence of herbivores in plant‐arthropod systems. [ABSTRACT FROM AUTHOR]

Houia is a possible annectent form between horseshoe crabs and eurypterids (sea scorpions). However, fossils are rare, previously only known from a single locality. Here, we report a new species of this genus, Houia guangxiensis sp. nov., from the Lower Devonian Cangwu Formation of Guangxi Province, South China. This discovery extends the geographical distribution of Houia from the Yangtze to the Cathaysia Block, supporting the living age of this genus in the Early Devonian (Lochkovian–Emsian). It not only adds to the record of this rare 'intermediate' form but also suggests potential relationships of shallow‐water species in the Yangtze and Cathaysia blocks. [ABSTRACT FROM AUTHOR]

A comprehensive study of the intertidal oribatid mite fauna of southern Japanese islands revealed the presence of the selenoribatid Arotrobates granulatus Luxton, 1992 and two yet undescribed species. The latter are herein described as Indopacifica taiyo n. sp., occurring from the Southern to the Central Ryukyus, and Indopacifica tyida n. sp., which was only found on the most western island of the Ryukyus, namely Yonaguni. A concomitant molecular genetic study using mitochondrial COI and 18S rRNA gene sequences, demonstrated that the phylogeographic pattern of I. taiyo n. sp. reflects recent expansion on the Southern and Central Ryukyus, probably due to existing land bridges during the late Pleistocene. Arotrobates granulatus, on the other hand, shows three distinct lineages, one on Japanese mainland, another on the island of Amami, and the third on part of the Central and Southern Ryukyus. These lineages are most likely the result of the break‐up of a large peninsula reaching from China to the Northern Ryukyus about 1.2–1.7 million years ago. Despite emerging land bridges in the late Pleistocene, this species was not able to expand its range again which indicates very low dispersal abilities. Morphometric data of I. taiyo n. sp. show considerable intraspecific variation between island populations correlating with geography. This found variation is suggested to be a result of phenotypic plasticity caused by diverging local environmental factors. From an ecological perspective, all three found species are classified as intertidal rock‐dwellers feeding on diverse algae, whereas I. taiyo n. sp. and Arotrobates granulatus occasionally occur in mangrove habitats. [ABSTRACT FROM AUTHOR]

Background The oriental river prawn, Macrobrachium nipponense , is an economically important shrimp in China. Male prawns have higher commercial value than females because the former grow faster and reach larger sizes. It is therefore important to reveal sex-differentiation and development mechanisms of the oriental river prawn to enable genetic improvement. Results We sequenced 293.3 Gb of raw Illumina short reads and 405.7 Gb of Pacific Biosciences long reads. The final whole-genome assembly of the Oriental river prawn was ∼4.5 Gb in size, with predictions of 44,086 protein-coding genes. A total of 49 chromosomes were determined, with an anchor ratio of 94.7% and a scaffold N50 of 86.8 Mb. A whole-genome duplication event was deduced to have happened 109.8 million years ago. By integration of genome and transcriptome data, 21 genes were predicted as sex-related candidate genes. Conclusion The first high-quality chromosome-level genome assembly of the oriental river prawn was obtained. These genomic data, along with transcriptome sequences, are essential for understanding sex-differentiation and development mechanisms in the oriental river prawn, as well as providing genetic resources for in-depth studies on developmental and evolutionary biology in arthropods. [ABSTRACT FROM AUTHOR]

Neonicotinoids are the most widely used insecticide class worldwide, and unfortunately, the widely used neonicotinoid imidacloprid is problematic for pollinators and other nontarget organisms. These nontarget impacts and the development of resistance prompt the ongoing development and testing of new neonicotinoids. The novel neonicotinoid cycloxaprid was described in 2011 and registered in China in 2015. Studies investigating its use and effect on target and nontarget species are recent and ongoing, and empirical evidence has not yet been collectively considered. Therefore, a systematic review was performed to identify and summarize data associated with target and nontarget, lethal and sublethal impacts of cycloxaprid for its use as a new insecticide. We performed keyword literature searches in Web of Science, PubMed, Academic Search Complete, and Google Scholar and explored citations used in identified articles. The search strategy yielded 66 citations; 25 citations fulfilled eligibility criteria and were included in the review. Under experimental conditions, cycloxaprid reduced populations of plant‐feeding insect pests, suppressed populations of sucking and biting insect pests, and affected reproduction, development time, longevity, growth, gene regulation and expression, and phloem‐feeding behavior of various life stages of certain insects. Studies focus on pest control efficacy and comparison with imidacloprid. Five nontarget organisms have been evaluated: Apis mellifera, Chrysoperla sinica, Harmonia axyridis, Daphnia magna, and Eisenia fetida. Variation in study design, to date, precludes a metaanalysis. However, these results provide valuable insight into possible effects to target and nontarget arthropods. Because cycloxaprid is a new insecticide, additional research is needed to clarify the mechanism of action of cycloxaprid and its metabolites, and to determine if it harms natural enemies or other nontarget organisms, if resistance develops, and if it exhibits cross‐resistance with other insecticides. Although research on target arthropods will inform some effects on nontarget organisms, studies focusing explicitly on impacts to nontarget organisms are needed. Integr Environ Assess Manag 2020;16:831–840. © 2020 SETAC KEY POINTS: Data from studies indicate that under experimental conditions, the proposed imidacloprid replacement cycloxaprid has lethal and sublethal effects on nontarget species, that is, Apis mellifera, Chrysoperla sinica, Harmonia axyridis, Daphnia magna, and Eisenia fetida.Cycloxaprid concentrations causing mortality in the target and nontarget arthropod species tested were generally lower than or similar to concentrations of imidacloprid.Cycloxaprid readiness for insect pest control is premature.Future studies focusing explicitly on impacts to nontarget organisms are needed. [ABSTRACT FROM AUTHOR]

Bark beetle galleries are complex ecosystems where many microbes and other arthropods co-exist with the beetles. Fungi isolated from these galleries are often referred to as 'beetle associates', but the nature of these associations are poorly understood. The possibility that many of these fungi might in fact be mite associates is often overlooked. Several recent studies explored the diversity of fungi from conifer-infesting bark beetles and their galleries in China, but only one study considered phoretic mites and their fungi from conifer-infesting bark beetles in Yunnan, southwestern China. We studied the mites and fungi from galleries of four spruce-infesting bark beetle species in the high altitude forests of Qinghai province, western China. Mites were identified based on morphological characteristics, and fungi based on DNA sequences of four gene regions. In total, 173 mite individuals were collected belonging to 18 species in 11 genera. A total of 135 fungal isolates were obtained from the mites, representing 14 taxa from the Ophiostomatales. The most frequently isolated fungus was Ophiostoma nitidum, which represented 23.5% of the total isolates. More fungal species were found from fewer mites and bark beetle species than from the study in Yunnan. Although we could not elucidate the exact nature of interactions between mites and their fungi, our results re-enforce that these organisms should not be ignored in pest risk assessments of bark beetles, that often focus only on the beetles and their fungi. Three new species are described: Grosmannia zekuensis, O. manchongi, and O. kunlunense spp. nov., and our data revealed that O. typographi, recently described from China, is a synonym of O. ainoae. [ABSTRACT FROM AUTHOR]

Hydrachnidiae are the most abundant and diverse groups of benthic arthropods. Seven superfamilies are included in the subcohort Hydrachnidiae, six of which have been reported from China. In our recent collection, we found several specimens of Hydrovolzia. The specimens were identified as Hydrovolzia cancellata Walter, 1906 using morphological characteristics. DNA barcodes were generated and represent the first reported for this species. Interspecific divergence between H. cancellata and H. placophora was analysed based on DNA barcodes. The result showed that the two species could be distinguished easily by DNA barcodes. The presence of H. cancellata in China means that seven superfamilies are officially reported in the country. [ABSTRACT FROM AUTHOR]

The arthropod Sidneyia Walcott, 1911 is a remarkable animal of the Burgess Shale biota (Cambrian Miaolingian, Wuliuan; British Columbia, Canada), which has not been confidently reported from other Cambrian Konservat-Lagerstätten. Here we report the discovery of Sidneyia cf. inexpectans from the Wuliuan Mantou Formation of North China, which substantially expands the known palaeogeographical distribution of this genus. Our discovery suggests that Sidneyia had much greater dispersal ability than hitherto thought. It also confirms the presence of exceptionally preserved fossils in the Wuliuan Mantou Formation, one of the rare Burgess Shale-type deposits of North China. [ABSTRACT FROM AUTHOR]

The trilobite Redlichia Cossmann, 1902 is an abundant element of the lower Cambrian (Series 2, Stage 4) Emu Bay Shale (EBS) Konservat-Lagerstätte on Kangaroo Island, South Australia. Well-preserved, fully articulated specimens from this deposit are known to reach lengths of up to 25 cm, representing one of the largest known Cambrian trilobites. Until now, all Redlichia specimens from the EBS have been referred to Redlichia takooensis Lu, 1950, a species originally described from South China. Previous work recognized considerable differences in exoskeletal morphology among specimens of varying sizes, which was attributed to ontogeny. However, close examination of a large collection of recently acquired specimens shows that this variation actually represents two distinct morphs, interpreted here as separate species: R. takooensis, and a large, new species, Redlichia rex sp. nov. An analysis of morphological variation in holaspides ('adults') of the more common R. takooensis reveals considerable ontogenetic change occurred even during this later phase of growth. Some specimens of both Redlichia species from the EBS also exhibit exceptionally preserved soft-part anatomy, particularly the antennae and biramous appendages. Here, appendages (antenniform and biramous) and digestive structures are described, and biramous appendage reconstructions of R. rex sp. nov. are presented, which show a striking resemblance to some early Cambrian trilobites from South China. In particular, R. rex has a tripartite exopodite, as well as a dorsoventrally deep protopodite with gnathobasic spines used to shred or crush food items. Based on recent phylogenetic analyses, it is possible that an exopodite with tripartite subdivisions represents the plesiomorphic condition for Artiopoda (trilobites and kin). The digestive system of R. takooensis exhibits a series of paired digestive glands in the cephalon and anterior thorax, similar to those described for a number of other Cambrian and Ordovician trilobites. [ABSTRACT FROM AUTHOR]

Riparian zones are interesting habitats as they are important transitional zones between terrestrial and aquatic ecosystems, but highly threatened by human disturbances. They support a high arthropod diversity as they experience periodic flooding disturbance and sharp environmental gradients. Their associated arthropod fauna are of high conservation value. Nevertheless, their arthropod diversity remains largely unknown, and its distribution pattern along elevational gradients is poorly understood. Few data are available on the effects of flood regimes and other factors in determining riparian arthropod communities. In this study, we investigated the diversity and distribution of riparian arthropods along an elevational gradient and determined the major factors structuring the arthropod communities in the drawdown zone of the Three Gorges Reservoir, China. Significant compositional and structural changes of riparian arthropod communities were observed along the test elevational gradient. The abundance and richness of riparian arthropods increased with elevation. The relative abundance of predators decreased with elevation, whereas the saprovores and omnivores showed an upward trend along the elevational gradient. Redundancy analysis showed that there were significant interactions between the flood regimes, plant communities, and soil conditions. Among these environmental factors studied, flood duration was the main factor in structuring the riparian arthropod communities. Conservation and restoration strategies should consider flood duration in the operation of large reservoirs because riparian arthropods are particularly sensitive to flood regimes. [ABSTRACT FROM AUTHOR]

We recently reported Cambrowania ovata Tang and Xiao in Tang et al., 2019, from the early Cambrian Hetang Formation in South China and interpreted it as a problematic animal fossil, possibly related to either sponges or bivalved arthropods (Tang et al., 2019). Slater and Budd (2019) contested our taxonomic identification and phylogenetic interpretation; instead, they claimed that Cambrowania ovata is a large acritarch referable to morphotaxon Leiosphaeridia Eisenack, 1958, and thus is not an animal. Here we refute their criticisms, clarify the differences between Cambrowania and Leiosphaeridia and other acritarchs, and reiterate why an animal affinity for Cambrowania cannot be ruled out. [ABSTRACT FROM AUTHOR]

Aim: China's Grain for Green Program (GFGP) is the largest reforestation programme in the world and has been operating since 1999. The GFGP has promoted the establishment of tree plantations over the restoration of diverse native forests. In a previous study, we showed that native forests support a higher species richness and abundance of birds and bees than do GFGP plantations and that mixed‐species GFGP plantations support a higher level of bird (but not bee) diversity than do any individual GFGP monocultures (although still below that of native forests). Here, we use metabarcoding of arthropod diversity to test the generality of these results. Location: Sichuan, China. Methods: We sampled arthropod communities using pan traps in the land cover types concerned under the GFGP. These land use types include croplands (the land cover being reforested under the GFGP), native forests (the reference ecosystem as the benchmark for the GFGP's biodiversity effects) and the dominant GFGP reforestation outcomes: monoculture and mixed‐species plantations. We used COI‐amplicon sequencing ("metabarcoding") of the arthropod samples to quantify and assess the arthropod community profiles associated with each land cover type. Results: Native forests support the highest overall levels of arthropod species diversity, followed by mixed‐species plantations, followed by bamboo and other monocultures. Also, the arthropod community in native forests shares more species with mixed‐species plantations than it does with any of the monocultures. Together, these results broadly corroborate our previous conclusions on birds and bees but show a higher arthropod biodiversity value of mixed‐species plantations than previously indicated by bees alone. Main conclusion: In our previous study, we recommended that GFGP should prioritize the conservation and restoration of native forests. Also, where plantations are to be used, we recommended that the GFGP should promote mixed‐species arrangements over monocultures. Both these recommendations should result in more effective protection of terrestrial biodiversity, which is an important objective of China's land‐sustainability spending. The results of this study strengthen these recommendations because our policy prescriptions are now also based on a dataset that includes over 500 species‐resolution taxa, ranging across the Arthropoda. [ABSTRACT FROM AUTHOR]

Japanese Encephalitis virus (JEV) is a zoonotic flavivirus that represents the most significant etiology of childhood viral neurological infections throughout the Asia. During the last 20 years, JEV genotype dominance has shifted from genotype III (GIII) to genotype I (GI). To date, the exact mechanism of this displacement is still not known. Culex (Cx.) mosquitoes are the most common species in China and play an essential role in maintaining JEV enzootic transmission cycle. In this study, we used Cx. pipiens mosquitoes from China as an in vivo mosquito model to explore if mosquitoes played a potential role in JEV genotype shift. We exposed female Cx. pipiens mosquitoes orally to either GI or GIII JEV strains. Midgut, whole mosquitoes, secondary organs, and salivary glands of JEV-infected mosquitoes were collected at 7 and 14 days of post infection (dpi) and subjected to measure the infection rate, replication kinetics, dissemination rate and transmission potential of the infected JEV strains in Cx. pipiens mosquitoes by 50% tissue culture infective dose assay. We found that Cx. pipiens mosquito was competent vector for both GI and GIII JEV infection, with similar infection rates and growth kinetics. After the establishment of infection, Cx. pipiens mosquitoes disseminated both JEV genotypes to secondary organs at similar rates of dissemination. A few GI-infected mosquito salivary glands (16.2%) were positive for GI virus, whereas GIII virus was undetectable in GIII-infected mosquito salivary glands at 7 dpi. However, 29.4% (5/17) and 36.3% (8/22) were positive for GI- and GIII-infected mosquito salivary glands at 14 dpi, respectively, showing an increase in JEV positive rate. No statistical difference in the transmission rate between GI- and GIII-infected mosquitoes was detected. Our experiment data demonstrated that GI and GIII viruses have similar infectivity in Cx. pipiens mosquitoes, suggesting that Cx. pipiens mosquitoes from China may not play a critical role in JEV genotype shift. Although the current data were obtained solely from Cx. pipiens mosquitoes, it is likely that the conclusion drawn could be extrapolated to the role of mosquitoes in JEV genotype shift. [ABSTRACT FROM AUTHOR]

The Guanshan Biota (Cambrian Series 2, Stage 4) is a typical Burgess Shale-type biota, and is one of the most significant Cambrian Konservat-Lagerstätten from China, in addition to the well-known Chengjiang and Kaili biotas. Guangweicaris is a relatively common arthropod from the Guanshan Biota. Based on new specimens from the Longbaoshan and Xinglongcun sections of the Wulongqing Formation in Kunming, we herein report novel features of Guangweicaris spinatus, such as the eye-bearing anterior sclerite that is associated with the head shield, as well as revised details of the trunk, including the ventral appendages. A detailed comparison of Guangweicaris, Fuxianhuia and Shankouia suggests a close affinity between Guangweicaris and Fuxianhuia, which improves our understanding of the evolution of early Cambrian euarthropods. [ABSTRACT FROM AUTHOR]

Background: The reported incidence of dengue fever increased dramatically in recent years in China. This study aimed to investigate and to assess the effectiveness of intervention implemented in a dengue outbreak in Ningbo City, Zhejiang Province, China. Methods: Data of a dengue outbreak were collected in Ningbo City in China by a field epidemiological survey according to a strict protocol and case definition. Serum specimens of all cases were collected for diagnosis and the virological characteristics were detected by using polymerase chain reaction (PCR) and gene sequencing. Vector surveillance was implemented during the outbreak to collect the larva and adult mosquito densities to calculate the Breteau Index (BI) and human biting rate (HBR), respectively. Data of monthly BI and light-trap density in 2018 were built to calculate the seasonality of the vector. A transmission mathematical model was developed to dynamic the incidence of the disease. The parameters of the model were estimated by the data of the outbreak and vector surveillance data in 2018. The effectiveness of the interventions implemented during the outbreak was assessed by the data and the modelling. Results: From 11 August to 8 September, 2018, a dengue outbreak was reported with 27 confirmed cases in a population of 5536-people community (community A) of Ningbo City. Whole E gene sequences were obtained from 24 cases and were confirmed as dengue virus type 1 (DENV-1). The transmission source of the outbreak was origin from community B where a dengue case having the same E gene sequence was onset on 30 July. Aedes albopictus was the only vector species in the area. The value of BI and HBR was 57.5 and 12 per person per hour respectively on 18 August, 2018 and decreased dramatically after interventions. The transmission model fitted well (χ2 = 6.324, P = 0.388) with the reported cases data. With no intervention, the total simulated number of the cases would be 1728 with a total attack rate (TAR) of 31.21% (95%CI: 29.99%– 32.43%). Case isolation and larva control (LC) have almost the same TAR and duration of outbreak (DO) as no intervention. Different levels of reducing HBR (rHBR) had different effectiveness with TARs ranging from 1.05% to 31.21% and DOs ranging from 27 days to 102 days. Adult vector control (AVC) had a very low TAR and DO. “LC+AVC” had a similar TAR and DO as that of AVC. “rHBR100%+LC”, “rHBR100%+AVC”, “rHBR100%+LC+AVC” and “rHBR100%+LC+AVC+Iso” had the same effectiveness. Conclusions: Without intervention, DENV-1 could be transmitted rapidly within a short period of time and leads to high attack rate in community in China. AVC or rHBR should be recommended as primary interventions to control rapid transmission of the dengue virus at the early stage of an outbreak. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome virus (SFTSV), an emerging human pathogen naturally transmitted by ticks, has spread widely since it was first detected in 2010. Although SFTSV-specific antibodies have been detected in wild birds, these natural reservoir and amplifying hosts for the virus have not been well studied. Methodology/Principle findings: Here we report an experimental infection of spotted doves (Streptopelia chinensis) with two strains of SFTSV, JS2010-14, a Chinese lineage strain, and JS2014-16, a Japanese lineage strain, which represent the main viral genotypes currently circulating in East Asia. In these studies, we have determined that spotted doves are susceptible to SFTSV and the severity of the viremia is dose-dependent. When challenged with 107 and 105 PFU, all doves developed viremia which peaked 3–5 days post infection (dpi). Only a subset (25–62.5%) of the birds developed viremia when challenged at 103 PFU. Virulence of SFTSV in spotted doves was strain dependent. Infection with 107 PFU of strain JS2014-16 resulted in 12.5% mortality over 6.8 days and mean peak viremia titers of 106.9 PFU/mL in experimentally inoculated birds. All doves inoculated with 107 PFU of the JS2010-14 strain survived infection with relatively lower mean viremia titers (105.6 PFU/mL at peak) over 6.1 days. Conclusions/Significance: Our results suggest that spotted doves, one of the most abundant bird species in China, could be a competent amplifying host for SFTSV and play an important role in its ecology. Between the two SFTSV strains, the strain of the Japanese lineage caused mortality, higher viremia titers in infected birds over a longer time period than did the Chinese strain. Our observations shed light on the ecology of SFTSV, which could benefit the implementation of surveillance and control programs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Aquarius lunpolaensis (Lin) from the late Oligocene of central Tibet is redescribed. • " Halobates bagonensis " should be interpreted as an exuvium of Aquarius lunpolaensis. • The extant Aquarius najas -group was much wider distributed in the late Oligocene. • The findings support the hypothesis that the elevation of central Tibet was low, some 25 million years ago. Abstract The semi-aquatic hemipteran family Gerridae (water striders), similar to other gerromorphan bugs, is a distinct group noted for their ability to walk on the surface of water, especially with respect to their locomotion, feeding, and behaviour. The three principal Holarctic gerrine genera, Aquarius Schellenberg, Gerris Fabricius and Limnoporus Stål, are important organisms for studies of biogeography, evolutionary trends and ecological adaptations of the Gerridae. Fossil gerrids are comparatively sparse, and direct fossil evidence elucidating the early diversification and biogeography of the extant widespread genus Aquarius remains elusive. Here we redescribe and reinterpret the extinct species Aquarius lunpolaensis (Lin, 1981) based on new well-preserved conspecific specimens from contemporaneous localities in the Lunpola and Nima basins of central Tibet, China. The new fossils confirm the placement of these fossils in Aquarius as evidenced by their large body size, first antennal segment longer than the following two segments combined, and well-developed abdominal connexival spines. The new discovery of a series of larval instars at different developmental stages confirms that " Halobates bagonensis " should be interpreted as an exuvium of the dominant species Aquarius lunpolaensis and demonstrates that the extant western Palaearctic najas -group had a much wider distribution in the late Oligocene (Chattian). The occurrence of an Aquarius water skater supports the hypothesis that the elevation of central Tibet was comparatively low, some 25 million years ago. [ABSTRACT FROM AUTHOR]

The chive gnat, Bradysia odoriphaga, is a notorious pest of Allium species in China. Colour trapping is an established method for monitoring and control of Bradysia species. In order to clarify the effect of colour preference of B. odoriphaga for the perched substrate, multiple-choice tests were used to assess the response of the chive gnat to different colour hues and brightness levels under different intensities of white illumination and two spectrally different illuminations. Given the choice among four colours differing in hue under different intensities of white illumination and two spectrally different illuminations, chive gnat adults significant preferred the black substrate, a lesser preference to brown and green substrates, and the least preference to orange substrate irrespective of illumination. Given the choice among four levels of brightness under the same illumination conditions as those in the previous experiment (different intensities of white illumination and two spectrally different illuminations), chive gnats preferred black substrate over dark grey, light grey and white substrates. Meanwhile, both virgin and mated adults significantly preferred black over other colour hues and brightness. Based on our results, we conclude that the chive gnat adults significantly prefer black substrates irrespective of colour hues and brightness. This behaviour does not alter with ambient light condition changes. No difference observed between choices of female and male adults. Our results provide new insight for understanding the colour choice behaviour in chive gnat and pave a way to improve monitoring and control of chive gnats and management. [ABSTRACT FROM AUTHOR]

Background: Numerous urban villages (UVs) and frequent infectious disease outbreaks are major environmental and public health concerns in highly urbanized regions, especially in developing countries. However, the spatial and quantitative associations between UVs and infections remain little understood on a fine scale. Methodology and principal findings: In this study, the relationships between reported dengue fever (DF) epidemics during 2012–2017, gross domestic product (GDP), the traffic system (road density, bus and/or subway stations), and UVs derived from high-resolution remotely sensed imagery in the central area of Guangzhou, were explored using geographically weighted regression (GWR) models based on a 1 km × 1 km grid scale. Accounting for 16.53%–18.07% of residential area and 16.84%–18.02% of population, UVs possessed 28.55%–38.24% of total reported DF cases in the core area of Guangzhou. The density of DF cases and the DF incidence rates in UVs were 1.81–3.13 and 1.82–3.06 times of that of normal construction land. Approximately 90% of the total cases were concentrated in the UVs and their buffering zones of radius ranged from 0 to 500 m. Significantly positive associations were observed between gridded DF incidence rates and UV area (r = 0.33, P = 0.000), the number of bus stops (r = 0.49, P = 0.000) and subway stations (r = 0.27, P = 0.000), and road density (r = 0.39, P = 0.000). About 60% of spatial variations in the gridded DF incidence rates were interpreted by the different variables of GDP, UVs, and bus stops integrated in GWR models. Conclusions: UVs likely acted as special transfer stations, receiving and/or exporting DF cases during epidemics. This work increases our understanding of the influences of UVs on vector-borne diseases in highly urbanized areas, supplying valuable clues to local authorities making targeted interventions for the prevention and control of DF epidemics. [ABSTRACT FROM AUTHOR]

Japanese encephalitis virus (JEV) genotype dominance has shifted to genotype I (GI) from genotype III (GIII) in China as demonstrated by molecular epidemiological surveillance. In this study, we performed a serological survey in JEV-non-vaccinated pigs to confirm JEV genotype shift at the sero-epidemiological level. The average ratio of GI/GIII infection was 1.87, suggesting co-circulation of GI and GIII infections with GI infection being more prevalent in pigs in China. To gain an insight into the reasons for this JEV genotype shift, the replication kinetics of seven recently-isolated JEV isolates including three GI strains and four GIII strains were compared in mosquito C6/36 cells, chicken fibroblast cells (DF-1) and porcine iliac artery endothelial cells (PIEC). We observed that GI strains replicated more efficiently than GIII strains in DF-1 and PIEC cells, particularly in DF-1 cells with titers reaching 22.9–225.3 fold higher than GIII strains. This shows an enhanced replication efficiency of GI viruses in avian cells. To examine this enhanced replication efficiency in vivo, young domestic ducklings were used as the animal model and inoculated with GI and GIII strains at day 2 post-hatching. We observed that GI-inoculated ducklings developed higher viremia titers and displayed a comparatively longer viremic duration than GIII-inoculated ducklings. These results conform to the hypothesis of an enhanced replication efficiency for GI viruses in birds. There are 36 amino acid differences between GI and GIII viruses, some of which may be responsible for the enhanced replication efficiency of GI viruses in birds. Based on these findings, we speculated that the enhanced replication of GI viruses in birds would have resulted in higher exposure and therefore infection in mosquitoes, which could result in an increased transmission efficiency of GI viruses in the birds-mosquitoes-birds enzootic transmission cycle, thereby contributing to JEV genotype shift. [ABSTRACT FROM AUTHOR]

Urbanization-induced environmental changes such as habitat fragmentation impact arthropod assemblages and food web-related ecosystem functions, such as nutrient cycling and energy fluxes. Yet, we lack insight into how arthropod food webs are structured along urban fragmentation gradients. Here, we investigated the community composition and food web structure of litter-dwelling arthropods along fragmentation gradients (green median strip, i.e. green fragments in the middle of roads, urban park, urban forest and natural forest) in Xiamen City, southeast China. We found the density of litter-dwelling arthropods in median strips and urban parks to be two to four times higher than in urban and natural forests, with, as indicated by literature-based stable isotope values, 67%–68% of the individuals comprising primary consumers (trophic level I). Consequently, more complex food webs were found in small urban fragments (i.e., green median strip and urban park) than in the other fragments studied, including higher linkage density and higher energy flux. The biomass of litter on the floor was significantly correlated with the density of arthropods of trophic levels I, III and IV, and each trophic guild positively correlated with each other pointing to the dominance of bottom-up forces. Overall, our results suggest that small urban fragments maintain a high density of arthropods forming complex food webs and thereby may contribute to maintaining high energy fluxes and providing important ecosystem functions in urban areas. [Display omitted] • Structural changes in arthropodan food web along urban fragment size, using fluxweb package. • Food webs of litter-dwelling arthropods in urban fragments were complex and structured. • Small fragments had more complex food web structures than natural forest. • Urban forest had the simplest food web structure, but presented as urban biodiversity hotspot. • The density of adjacent trophic levels correlated positively indicating bottom-up control. [ABSTRACT FROM AUTHOR]

• A first quantitative study of Wuchiapingian plant-insect interactions from Cathaysia. • Nineteen damage types grouped to six functional feeding groups were identified. • Herbivore arthropods preferred the relatively abundant and more apparent foliage. • Local provincialism of plant–arthropod associations existed in Lopingian Cathaysia. • Margin-feeding culprits were one of the dominant herbivores in the Permian floras. The Permian is a pivotal time interval for the evolution of the terrestrial realm while the evolutionary dynamics of both floral and faunal turnover are poorly understood. Fossil evidence of plant–arthropod associations allows us to explore these confusions. In this paper, plant–arthropod interactions from the Wuchiapingian Qinglong plant assemblage in southwestern China are analysed. Fifty-one damage occurrences attributed to 19 damage types (DTs) from six functional feeding groups were recognised, consisting of hole feeding, margin feeding, surface feeding, piercing-and-sucking, oviposition, and galling. Although broadleaved gigantopterid laminae were less abundant than strap-shaped taeniopterid foliage, the former had more DT richness as well as DT frequency (occurrences based on presence-absence data) than those of the latter, indicating that herbivorous arthropods preferentially targeted broadleaved gigantopterid foliage and providing additional support for the apparency hypothesis. To explore the evolutionary dynamics of Permian plant–arthropod associations, data of DT community composition in the Qinglong and seven other Permian assemblages were analyzed using principal component analysis (PCA) and rank-abundance curve (RAC). PCA result shows that the Qinglong plant–arthropod associations displayed a damage-type spectrum with minimal affinity to those in the South China Kayitou and other assemblages, indicating that there was no compositional similarity of plant–arthropod associations in the Qinglong and other ecosystems. This pattern is probably related to different climatic zonation which resulted in local provincialism of plant–arthropod associations. RAC result shows that margin feeding was the dominant feeding modes during the Permian, suggesting there were a relatively high richness of margin-feeding culprits in these ecosystems. [ABSTRACT FROM AUTHOR]

Aphids are major pests of cotton crops in the Xinjiang Uygur Autonomous Region in China, and parasitoids are considered as important natural enemies in regulating aphid populations. However, information on aphid parasitoids in the Xinjiang cotton fields is limited, which hinders the study of aphid-parasitoid interactions and the application of conservation biological control against cotton aphids. In this study, a 3-year survey was conducted in a large geographical range that included three primary cotton planting areas in southern and northern Xinjiang. The population dynamics and the parasitism levels of an assemblage of aphids in the cotton fields were investigated along with the composition of the parasitoid community associated with these aphids. Aphid parasitization varied significantly within both years and seasons, with parasitism levels ranging from 0 to 26%, indicating that there is less effective biological control of parasitoids on aphids under field conditions. Among the primary parasitoids described, Binodoxys communis (Gahan) constituted 95.19% of the parasitoid species, followed by Praon barbatum Mackauer (3.15%), Trioxys asiaticus Telenga (1.01%) and Lysiphlebus fabarum Marshall (0.65%). Significant differences were found in the composition of the primary parasitoid species between the cotton seedling period (June) and the flowering period (July-August), and two more primary aphid parasitoids were found in the seedling period. Twelve hyperparasitoid species belonging to six genera were found in our study, of which Pachyneuron aphidis (Bouché), Syrphophagus species and Dendrocerus laticeps (Hedicke) were the dominant species. The composition of the hyperparasitoid community also differed significantly between the seedling and the flowering periods. The description of this parasitoid community-associated assemblage of aphids in cotton fields will facilitate the study of aphid-parasitoid interactions and promote the development of effective cotton aphid management strategies in Xinjiang. [ABSTRACT FROM AUTHOR]

Background: The near-surface urban drainage system in Shanghai is highly complex, with hundreds of thousands of catch basins (CBs) and manhole chambers (MCs). Comparatively little is known about the breeding of mosquitoes in this vast system, especially for the locally predominant species Aedes albopictus. A cross-sectional mosquito sampling study was conducted from late July to early August of 2017 using 539 CBs and 309 MCs located in 10 communities of downtown Shanghai. We measured the water-holding status of the drainage systems and density of mosquito larvae. Mosquito species were examined on site and in the laboratory later. Results: The CBs were characterized by a lower percentage of standing water compared to MCs (47.0% vs. 79.9%, respectively; X2 = 76.407, P<0.001), but CBs contained a higher percentage of stagnant water percent than MCs (45.2% vs. 35.3%, respectively; X2 = 11.465, P = 0.001). There were exclusively two species of mosquito larvae found in the drainage systems, Ae. albopictus and Culex pipiens complex. Compared with MCs, the structures of CBs were more conducive to larval production and yielded more larvae-positive samples (43.4% vs 14.2%, X2 = 53.136, P<0.001) and higher larval density (8.23 vs. 4.09 per dipper, t = 3.287, P = 0.001). Aedes albopictus was the predominant species in CBs, with a constituent ratio of 71.7%. Regarding structures with different features in different locations, CBs that had a vertical grate with an unsealed lid and MCs with plastic composite covers were the most favorable types for mosquito breeding, and residential neighborhoods yielded the highest number of Ae. albopictus. Conclusion: Aedes albopictus was the predominant species in both CBs and stormwater MCs, especially in residential neighborhoods. CBs, particularly those with vertical grates, were a major source of mosquito production in downtown Shanghai. MCs featured more running water and fewer larvae by percentage, and few larvae were found in Sewage MCs. However, due to the tremendous baseline amount, MCs were still an important breeding source of mosquitoes. We suggest that Aedes control in Shanghai should focus on CBs or other potential larvae habitats in and around residential neighborhoods. The use of permeable materials and completely sealed covers should be adopted in the construction of CBs and MCs henceforth. [ABSTRACT FROM AUTHOR]

This study assessed the enrichment of mercury in the food web from the different community habitats in a zinc-smelting area of China. We used a nitrogen stable isotope technique to analyze trophic level relationships among arthropods and found that the first trophic level consisted of plants in the different community habitats, the second trophic level consisted of herbivores such as locusts and grasshoppers (primary consumers), and the third trophic level included spiders and mantes (secondary consumers). Mercury enrichment in the primary consumers was not evident, but enrichment in arthropods of the third trophic level was significant. The average of enrichment coefficients in spiders and mantes was greater than 1. The δ15N values indicated that mercury concentrations accumulated from primary producers to top carnivorous arthropods increased. In this zinc-smelting area, the biological amplification of mercury in the food web is significant. It is reasonable to assume that humans, located at the top of the food chain, are exposed to biomagnified levels of mercury. [ABSTRACT FROM AUTHOR]

The oriental river prawn, Macrobrachium nipponense, is an important commercial aquaculture resource in China. In order to overwinter, M. nipponense displays decreased physiological activity and less consumption of energy. Sudden warming would trigger molting and cause an extensive death, resulting in huge economic losses. Therefore, it is of great practical significance to study the molting mechanism of oriental river prawns. Molt-inhibiting hormone gene (MIH) plays a major role in regulating molting in crustaceans. In this study, a full length MIH cDNA of M. nipponense (Mn-MIH) was cloned from the eyestalk. The total length of the Mn-MIH was 925 bp, encoding a protein of 119 amino acids. Tissue distribution analysis showed that Mn-MIH was highly expressed in the eyestalk, and that it had relatively low expression in gill, ovary, and abdominal ganglion. Mn-MIH was detected in all developmental stages, and changed regularly in line with the molting cycle of the embryo and larva. Mn-MIH varied in response to the molting cycle, suggesting that Mn-MIH negatively regulates ecdysteroidogenesis. Mn-MIH inhibition by RNAi resulted in a significant acceleration of molting cycles in both males and females, confirming the inhibitory role of MIH in molting. After long-term RNAi males, but not females had significant weight gain, confirming that Mn-MIH plays an important role in growth of M. nipponense. Our work contributes to a better understanding of the role of Mn-MIH in crustacean molting and growth. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the spatiotemporal clustering and socio-environmental factors associated with dengue fever (DF) incidence rates at street level in Guangzhou City, China. Methods: Spatiotemporal scan technique was applied to identify the high risk region of DF. Multiple regression model was used to identify the socio-environmental factors associated with DF infection. A Poisson regression model was employed to examine the spatiotemporal patterns in the spread of DF. Results: Spatial clusters of DF were primarily concentrated at the southwest part of Guangzhou City. Age group (65+ years) (Odd Ratio (OR) = 1.49, 95% Confidence Interval = 1.13 to 2.03), floating population (OR = 1.09, 95% CI = 1.05 to 1.15), low-education (OR = 1.08, 95% CI = 1.01 to 1.16) and non-agriculture (OR = 1.07, 95% CI = 1.03 to 1.11) were associated with DF transmission. Poisson regression results indicated that changes in DF incidence rates were significantly associated with longitude (β = -5.08, P<0.01) and latitude (β = -1.99, P<0.01). Conclusions: The study demonstrated that social-environmental factors may play an important role in DF transmission in Guangzhou. As geographic range of notified DF has significantly expanded over recent years, an early warning systems based on spatiotemporal model with socio-environmental is urgently needed to improve the effectiveness and efficiency of dengue control and prevention. [ABSTRACT FROM AUTHOR]

Transgenic Bt rice expressing the insecticidal proteins derived from Bacillus thuringiensis Berliner ( Bt) has been developed since 1989. Their ecological risks towards non-target organisms have been investigated; however, these studies were conducted individually, yielding uncertainty regarding potential agroecological risks associated with large-scale deployment of Bt rice lines. Here, we developed a meta-analysis of the existing literature to synthesize current knowledge of the impacts of Bt rice on functional arthropod guilds, including herbivores, predators, parasitoids and detritivores in laboratory and field studies. Laboratory results indicate Bt rice did not influence survival rate and developmental duration of herbivores, although exposure to Bt rice led to reduced egg laying, which correctly predicted their reduced abundance in Bt rice agroecosystems. Similarly, consuming prey exposed to Bt protein did not influence survival, development or fecundity of predators, indicating constant abundances of predators in Bt rice fields. Compared to control agroecosystems, parasitoid populations decreased slightly in Bt rice cropping systems, while detritivores increased. We draw two inferences. One, laboratory studies of Bt rice showing effects on ecological functional groups are mainly either consistent with or more conservative than results of field studies, and two, Bt rice will pose negligible risks to the non-target functional guilds in future large-scale Bt rice agroecosystems in China. [ABSTRACT FROM AUTHOR]

As a sustainable transportation mode, high-speed railway (HSR) has become an efficient way to meet the huge travel demand. However, due to the high acquisition and maintenance cost, it is impossible to build enough infrastructure and purchase enough train-sets. Great efforts are required to improve the transport capability of HSR. The utilization efficiency of train-sets (carrying tools of HSR) is one of the most important factors of the transport capacity of HSR. In order to enhance the utilization efficiency of the train-sets, this paper proposed a train-set circulation optimization model to minimize the total connection time. An innovative two-stage approach which contains segments generation and segments combination was designed to solve this model. In order to verify the feasibility of the proposed approach, an experiment was carried out in the Beijing-Tianjin passenger dedicated line, to fulfill a 174 trips train diagram. The model results showed that compared with the traditional Ant Colony Algorithm (ACA), the utilization efficiency of train-sets can be increased from 43.4% (ACA) to 46.9% (Two-Stage), and 1 train-set can be saved up to fulfill the same transportation tasks. The approach proposed in the study is faster and more stable than the traditional ones, by using which, the HSR staff can draw up the train-sets circulation plan more quickly and the utilization efficiency of the HSR system is also improved. [ABSTRACT FROM AUTHOR]

Oryctocephalus indicus is a widespread trilobite species described from the lower-middle Cambrian (provisional Cambrian Stage 5) of south China, North Korea, India, USA and possibly North Greenland. Principal component analysis ( PCA) and thin-plate splines ( TPSs) based on a pooled sample of 359 specimens from four sections in the Guizhou Province, south China, demonstrated that the shape of this species is very constant, and only a small difference is detected in specimens from deeper part of the basin. Most of the variation is taphonomically controlled, and only the specimens from Sanwan Section show a modest natural difference due to a slightly different depositional environment. A comparison between the Chinese specimens and Oryctocephalus 'reticulatus' from the Molodo Section, Siberia, has been carried out. PCA and TPS show that O. 'reticulatus occupies the same morphospace of O. indicus. However, the canonical variates analysis and the analysis of similarities detect small differences between the Siberian and Chinese populations, indicating a minor geographical variation caused by different environmental settings. The ontogenic variation is also described from early meraspids to holaspids. The most substantial changes take place during the first period of the early meraspid development, in which the glabella changes from a bell-like shape to a cylindrical shape. The ocular ridge changes from poorly defined in early meraspid to well developed in late merapids. The results indicate that O. 'reticulatus' is a junior synonym of O. indicus, suggesting that the base O. indicus of Siberia can be correlated with the O. indicus Zone of south China. [ABSTRACT FROM AUTHOR]

Top-down force is referred to arthropod pest management delivered by the organisms from higher trophic levels. In the context of prevalent adoption of transgenic Bt crops that produce insecticidal Cry proteins derived from Bacillus thuringiensis (Bt), it still remains elusive whether the top-down forces are affected by the insect-resistant traits that introduced into the Bt crops. We explored how Bt cotton affect the strength of top-down forces via arthropod natural enemies in regulating a non-target pest species, the cotton aphid Aphis gossypii Glover, using a comparative approach (i.e. Bt cotton vs. conventional cotton) under field conditions. To determine top-down forces, we manipulated predation/parasitism exposure of the aphid to their natural enemies using exclusion cages. We found that the aphid population growth was strongly suppressed by the dominant natural enemies including Coccinellids, spiders and Aphidiines parasitoids. Coccinellids, spiders and the assemblage of other arthropod natural enemies (mainly lacewings and Hemipteran bugs) are similarly abundant in both plots, but with the parasitoid mummies less abundant in Bt cotton plots compared to the conventional cotton plots. However, the lower abundance of parasitoids in Bt cotton plots alone did not translate into differential top-down control on A. gossypii populations compared to conventional ones. Overall, the top-down forces were equally strong in both plots. We conclude that transgenic Bt cotton does not disrupt the top-down forces regulating the cotton aphid in central China. [ABSTRACT FROM AUTHOR]

The author reflects on the negative effect of Zika virus transmission in the universal two-child policy in China. The author discusses the rapidly aging population in the country, the risk of developing microcephaly of central nervous system (CNS) malformations on people with Zika virus infection, and the technical guidance on how to handle the Zika virus epidemic.