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Abstract Pitaya (Hylocereus undulatus) is a significant cash crop in the karst region of Southwest China. Ecological stoichiometry is an essential method to research biogeochemical cycles and limiting elements. The purpose of this study was to explore the stoichiometric characteristics of C, N, and P in Karst pitaya orchards and fruit quality and to elucidate the mechanism and process of nutrient cycling. The results showed that: (1) Fruit quality was highest under the combination of chemical and organic fertilizers. Compared to the control, the contents of per-fruit weight, vitamin C, and soluble sugar increased significantly by 55.5%, 60.7%, and 23.0%, respectively, while the content of titratable acidity decreased significantly by 22.0%. (2) The content of soil nutrients under fertilization stress showed a downward trend in general, as did microbial biomass and extracellular enzyme activities. (3) Different fertilization treatments significantly affected the soil-microbial stoichiometry C:N ratio, C:P ratio, with research areas being significantly limited by C and P. (4) Spearman and PLS-SEM (partial least squares-structural equation model) analysis results showed that under the influence of fertilization, there was a significant positive effect between microorganisms and soil nutrients, but a significant negative effect between soil nutrients and quality. The results of this study offer an innovative perspective on pitaya quality research in Karst areas.

Four new erythroneurine leafhopper species, Empoascanara aparaoides Wang & Song, sp. nov., Motaga mengyangensis Wang & Song, sp. nov., Motaga acicularis Wang & Song, sp. nov., and Tautoneura qingxiuensis Wang & Song, sp. nov. from karst areas in Southwestern China, are described and illustrated.

Abstract Background Geographical factors affect the nutritional, therapeutic and commercial values of fruits. Dragon fruit (Hylocereus spp) is a popular fruit in Asia and a potential functional food with diverse pharmacological attributes. Although it is produced in various localities, the information related to the altitudinal variation of dragon fruit nutrients and active compounds is scarce. Hence, this study aimed to investigate the variations in metabolite profiles of H. polyrhizus (variety Jindu1) fruit pulps from three different altitudes of China, including Wangmo (WM, 650 m), Luodian (LD, 420 m), and Zhenning (ZN, 356 m). Jindu1 is the main cultivated pitaya variety in Guizhou province, China. Results The LC-MS (liquid chromatography-mass spectroscopy)-based widely targeted metabolic profiling identified 645 metabolites, of which flavonoids (22.64%), lipids (13.80%), phenolic acids (12.40%), amino acids and derivatives (10.39%), alkaloids (8.84%), and organic acids (8.37%) were dominant. Multivariate analyses unveiled that the metabolite profiles of the fruit differed regarding the altitude. Fruits from WM (highest altitude) were prime in quality, with higher levels of flavonoids, alkaloids, nucleotides and derivatives, amino acids and derivatives, and vitamins. Fruits from LD and ZN had the highest relative content of phenolic acids and terpenoids, respectively. We identified 69 significantly differentially accumulated metabolites across the pulps of the fruits from the three locations. KEGG analysis revealed that flavone and flavonol biosynthesis and isoflavonoid biosynthesis were the most differentially regulated. It was noteworthy that most active flavonoid compounds exhibited an increasing accumulation pattern along with the increase in altitude. Vitexin and isovitexin were the major differentially accumulated flavonoids. Furthermore, we identified two potential metabolic biomarkers (vitexin and kaempferol 3-O-[2-O-β-D-galactose-6-O-a-L-rhamnose]-β-D-glucoside) to discriminate between dragon fruits from different geographical origins. Conclusion Our findings provide insights into metabolic changes in dragon fruits grown at different altitudes. Furthermore, they show that growing pitaya at high altitudes can produce fruit with higher levels of bioactive compounds, particularly flavonoids.

Abstract Knowing the impacts of global climate change on the habitat suitability distribution of Limassolla leafhoppers contributes to understanding the feedback of organisms on climate change from a macroecological perspective, and provides important scientific basis for protecting the ecological environment and biodiversity. However, there is limited knowledge on this aspect. Thus, our study aimed to address this gap by analyzing Asian habitat suitability and centroid shifts of Limassolla based on 19 bioclimatic variables and occurrence records. Selecting five ecological niche models with the outstanding predictive performance (Maxlike, generalized linear model, generalized additive model, random forest, and maximum entropy) along with their ensemble model from 12 models, the current habitat suitability of Limassolla and its future habitat suitability under two Shared Socio‐economic Pathways (SSP1‐2.6 and SSP5‐8.5) in the 2050s and 2090s were predicted. The results showed that the prediction results of the five models are generally consistent. Based on ensemble model, 11 potential biodiversity hotspots with high suitability were identified. With climate change, the suitable range of Limassolla will experience both expansion and contraction. In SSP5‐8.52050s, the expansion area is 118.56 × 104 km2, while the contraction area is 25.40 × 104 km2; in SSP1‐2.62090s, the expansion area is 91.71 × 104 km2, and the contraction area is 26.54 × 104 km2. Furthermore, the distribution core of Limassolla will shift toward higher latitudes in the northeast direction, and the precipitation of warmest quarter was found to have the greatest impact on the distribution of Limassolla. Our research results supported our four hypotheses. Finally, this research suggests establishing ecological reserves in identified contraction to prevent habitat loss, enhancing the protection of biodiversity hotspots, and pursuing a sustainable development path with reduced emissions.

Soil microbiomes play a crucial role in enhancing plant growth, health, and overall agricultural productivity. Nevertheless, the influence of distinct agricultural management practices on the microbial diversity and community structure within tea (Camellia sinensis) plantations has remained enigmatic. This study postulates that organic agricultural management models can enhance microbial diversity and optimise the microbial community structure within tea plantations, indirectly augmenting soil fertility and tea quality. We employed metagenome technology and conducted molecular ecological network analysis to explore the impact of organic management, pollution-free management, and conventional management on the microbial network structure of tea plantation soil in Weng'an County in the southwestern karst region. Soils subjected to organic management exhibited a higher relative abundance of soil microbial and carbohydrate-active enzyme functional genes than those subjected to other management regimes. Additionally, the relative abundance and diversity of dominant bacteria and keystone species were notably higher under organic management than under the other management regimes. Correlation analysis showed that soil microorganisms were closely related to soil fertility and tea quality, respectively. One-way analysis of variance and the structural equation modelling results showed significant variability in soil fertility under the three agricultural management modes and that soil fertility and soil microbial diversity had a direct impact on tea quality (P > 0.05). In conclusion, this study underscores the profound impact of management modes on microbial diversity and community structure within tea plantations. These management practices alter the soil microbial network structure and potential function, ultimately regulating the microecological dynamics of the soil community in tea plantations.

Abstract Erythroneurini is the largest tribe of the microleafhopper subfamily Typhlocybinae. Most prior research on this tribe has focused on traditional classification, phylogeny, and control of agricultural pests, and the phylogeography of the group remains poorly understood. In this study, the mitochondrial genomes of 10 erythroneurine species were sequenced, and sequences of four genes were obtained for 12 geographical populations of Seriana bacilla. The new sequence data were combined with previously available mitochondrial DNA sequence data and analyzed using Bayesian and Maximum‐Likelihood‐based phylogenetic methods to elucidate relationships among genera and species and estimate divergence times. Seriana was shown to be derived from within Empoascanara. Phylogeographic and population genetic analysis of the endemic Chinese species Seriana bacilla suggest that the species diverged about 54.85 Mya (95% HPD: 20.76–66.23 million years) in the Paleogene period and that population divergence occurred within the last 14 million years. Ancestral area reconstruction indicates that Seriana bacilla may have originated in the central region of Guizhou, and geographical barriers are the main factors affecting gene flow among populations. Ecological niche modeling using the MaxEnt model suggests that the distribution of the species was more restricted in the past but is likely to expand in the future years 2050 and 2070.

Erythroneurine leafhoppers (Hemiptera, Cicadellidae, Typhlocybinae, Erythroneurini) are utilized to resolve the relationship between the four erythroneurine leafhopper (Hemiptera, Cicadellidae, Typhlocybinae, Erythroneurini): Arboridia (Arboridia) rongchangensis sp. nov., Thaia (Thaia) jiulongensis sp. nov., Mitjaevia bifurcata Luo, Song & Song, 2021 and Mitjaevia diana Luo, Song & Song, 2021, the two new species are described and illustrated. The mitochondrial gene sequences of these four species were determined to update the mitochondrial genome database of Erythroneurini. The mitochondrial genomes of four species shared high parallelism in nucleotide composition, base composition and gene order, comprising 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs) and an AT control region, which was consistent with majority of species in Cicadellidae; all genes revealed common trait of a positive AT skew and negative GC skew. The mitogenomes of four species were ultra-conservative in structure, and which isanalogous to that of others in size and A + T content. Phylogenetic trees based on the mitogenome data of these species and another 24 species were built employing the maximum likelihood and Bayesian inference methods. The results indicated that the four species belong to the tribe Erythroneurini, M. diana is the sister-group relationship of M. protuberanta + M. bifurcata. The two species Arboridia (Arboridia) rongchangensis sp. nov. and Thaia (Thaia) jiulongensis sp. nov. also have a relatively close genetic relationship with the genus Mitjaevia.

In this study, we sequenced and reported the complete mitochondrial genomes of Kusala populi for the first time. The complete mitochondrial genome was registered in GenBank with accession number NC_064377 as the first complete mitogenome of the genus Kusala. The circular mitochondrial genome length is 15,402 bp, with nucleotide composition A (41.8%), C (11.4%), G (9.2%), T (37.6%), A + T (79.4%), and C + G (20.6%), comprising 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a D-loop region. All protein-coding genes were encoded by the H-strand, except for 4 genes (nad5, nad4, nad4L, nad1). 8 tRNA genes (tRNA-Gln, tRNA-Cys, tRNA-Tyr, tRNA-Phe, tRNA-His, tRNA-Pro, tRNA-Leu, tRNA-Val) and 2 rRNA genes (16S, 12S) were encoded in the L-strand. Phylogenetic analysis indicated that the newly sequenced species had a close relationship with Mitjaevia, another widespread Old-World genus of Erythroneurini.

Abstract Biology and the environment are inextricably linked. Insects are intricately linked to their habitats as part of the ecosystem. In this study, scanning electron microscopy (SEM) observations showed two sensilla chaetica, several sensilla trichodea, and at least one sensilla basiconicum on the antennae of typhlocybine insects. There were no sensilla on the labrum; however, the surface morphology was different. There were more sensilla trichodea on the surface, mostly symmetrically distributed along the labial groove, and there was little difference in the structure of the stylet fascicle. The correlation between the sensilla number on the body surface of typhlocybine insects and environmental factors in the 3 study areas was as follows: Huajiang > Bijie > Shibing, which is consistent with the classification of rocky desertification grade; that is, the higher the rocky desertification grade, the greater the sensilla number on leafhoppers affected by the environment. The correlation between the number of leafhoppers and environmental factors in the 3 months was as follows: end of September > end of May > end of July, which was consistent with the changing temperature trends. The results of this study enrich our knowledge of the morphological characteristics of leafhoppers and explore the potential value of insect surface ultra‐morphology for use by humans.

Introduction: The tea green leafhopper, Empoasca (Matsumurasca) onukii Matsuda, R., 1952 (Hemiptera: Cicadellidae), is currently one of the most devastating pests in the Chinese tea industry. The long-term use of chemical pesticides has a negative impact on human health, impeding the healthy and sustainable development of the tea industry in this region. Therefore, there is a need for non-chemical insecticides to control E. onukii in tea plants. The essential oils from plants have been identified for their potential insecticidal ability; however, there is a lack of knowledge regarding the effect of plant essential oils on E. onukii and its gene expression.Methods: In order to address these knowledge gaps, the components of Pogostemon cablin and Cinnamomum camphora essential oils were analyzed in the present study using gas chromatography‐mass spectrometry. The fumigation toxicity of two essential oils on E. onukii was tested using sealed conical flasks. In addition, We performed comparative transcriptome analyses of E. onukii treated with or without P. cablin essential oil.Results: The 36-h lethal concentration (LC50) values for E. onukii treated with P. cablin and C. camphora essential oils were 0.474 and 1.204 μL mL−1 respectively. Both essential oils exhibited the potential to control E. onukii, but the fumigation activity of P. cablin essential oil was more effective. A total of 2,309 differentially expressed genes were obtained by transcriptome sequencing of E. onukii treated with P. cablin essential oil.Conclusion: Many of differentially expressed genes were found to contain detoxifification genes, indicating that these families may have played an important role when E. onukii was exposed to essential oil stress. We also found differential expression of genes related to redox-related gene families, suggesting the upregulation of genes associated with possible development of drug and stress resistance. This work offers new insights for the prevention and management of E. onukii in the future.

Three new species of the leafhopper genus Mitjaevia Dworakowska 1970, M. bijiensis sp. nov., M. solitaria sp. nov., and M. salaxia sp. nov., are described from the Karst region of Southwest China. Specimens studied were taken by sweep net. Morphological descriptions, depictions of habitus and illustrations of male terminalia are provided. A key and checklist to known species occurring in China are given.

This study describes the fine structure of the mouthparts, antennae, forewings, and brochosomes of two leafhopper species belonging to the typhlocybine tribe Erythroneurini collected from the Karst area of Guizhou Province, southern China: Singapora shinshana, which prefers woody dicot hosts, and Empoascanara sipra, which feeds on grasses. As in other leafhoppers, the piercing-sucking mouthparts consist of a conical labrum, a cylindrical three-segmented labium, and a slender stylet fascicle. The labrum of both species has no sensilla and the labium has several common types of sensilla, but the two species differ in the numbers, types, and distribution of sensilla and in other aspects of the surface sculpture of the mouthparts. The stylet fascicle has distinctive dentition on both the maxillary and mandibular stylets. The antennae of the two species differ in several respects, including the sensilla and sculpture of the scape, pedicel, and flagellum, as well as the degree of sub-segmentation of the flagellum. Except for the variable scaly structure and rounded protrusions on the surface of S. shinshana, the fine structure of the forewing surfaces of the two species are similar to those of other leafhoppers. Only small spherical brochosomes were found on the body surface of S. shinshana and E. sipra. Similar studies of additional erythroneurine species are needed to determine whether differences in mouthpart and antennal fine structure may reflect adaptation to different host plant.

The leafhopper genus Anufrievia was established by Dworakowska with A. rolikae Dworakowska as its type species. They are widely distributed in China, North Korea, South Korea, Japan, Nepal, India, Indonesia, Thailand and Vietnam.Two new species, A. ventricosa sp. nov. and A. unianxialis sp. nov., found in the karst area of Guanling and Shibing City, Guizhou Province, China are described and illustrated. The key to the identification of the specie of this genus is given.

The tea leafhopper (Empoasca (Matsumurasca) onukii Matsuda, 1952) is the predominant pest infesting tea and causes significant losses in yield. Plants have evolved multiple defense responses to protect themselves from insect herbivores. Camellia tetracocca, a kind of ancient tea with local popularity, is unique to southwest China. This ancient tea is often attacked by the tea leafhopper. However, there are no relevant reports on changes in volatile components and defense signaling pathways after Camellia tetracocca has been attacked by E. onukii. To reveal changes in the responses of the volatile components of C. tetracocca to E. onukii, the headspace sampling technique and GC-MS were adopted to determine and analyze the volatiles. Furthermore, to unveil the defense mechanisms of C. tetracocca in response to E. onukii, transcriptome analysis was applied to damaged tea leaves and healthy leaves. The GC-MS analysis showed significant increases in the linalool and (E)-2-hexenal contents. The transcriptome analysis revealed a set of core pest-responsive genes (3074 upregulated and 5098 downregulated). Most of the enriched pest-responsive genes are mainly involved in plant hormone signal transduction photosynthesis, terpenoid backbone biosynthesis, alpha-linolenic acid metabolism, and the NF-κB signaling pathway. A conjoint analysis of the transcriptome and metabolome indicated that N2-acetylornithine, D-malic acid, theogallin, fucosyllactose, 5-caffeoylquinic acid, fumarprotocetraric acid, and arabinogalactose have a significant correlation with LOC114279735, LOC114317534, LOC114282078, LOC114317768, and LOC114263181. This study lays a foundation for further research on the breeding and cultivation of insect-resistant germplasm resources for C. tetracocca and on the promotion and development of the plant.

Leafhoppers (Hemiptera, Auchenorrhyncha, Cicadellidae) are distributed worldwide and include around 2550 genera, more than 21,000 species, including almost 2000 species in China. Typhlocybinae is the second largest subfamily in Cicadellidae after Deltocephalinae. Previously, morphological characteristics were the diagnostic basis of taxonomy, but they were not combined with molecular biology. The genus Ziczacella Anufryev, 1970 has only six known species worldwide. The mitogenomes of Ziczacella steggerdai Ross, 1965, Ziczacella dworakowskae Anufriev, 1969 and Ziczacella heptapotamica Kusnezov, 1928 were sequenced and identified here for the first time. They all contained 13 PCGs, 22 tRNA genes, 2 rRNA genes, and a control region, and the complete mitochondrial genomes were 15,231 bp, 15,137 bp, and 15,334 bp, respectively. The results show heavy AT nucleotide bias. Phylogenetic analysis yielded the following topology: (Empoascini + Alebrini) + ((Erythroneurini + Dikraneurini) + (Zyginellini + Typhlocybini)). In this study, three newly sequenced species were closely related to Mitjaevia dworakowskae and M. shibingensis. We confirmed the monophyly of the four tribes within Typhlocybinae again, and Zyginellini should be combined with Typhlocybini, which supports Chris’s points.

The leafhopper genus Mitjaevia Dworakowska,1970 includes 19 species worldwide, nine species are known in China and is widely distributed in Palaearctic and Oriental RegionsTwo new species from Guizhou Province, China are described within the genus Mitjaevia Dworakowska, 1970 (Hemiptera: Cicadellidae: Typhlocybinae). A key to the species of the genus is provided and the female valvulae are described and figured.

The leafhopper genus Empoascanara was established by Distant (1918). So far, 81 species of the genus Empoascanara have been reported, most of which are distributed in Afrotropical or Oriental or Australian regions. The leafhopper genus Kapsa was established by Dworakowska (1972) and mainly distributed in the Orient or Australia.Two new species of the leafhopper tribe Erythroneurini from Guizhou province, China, Empoascanara dichotomus sp. nov. and Kapsa sinuose sp. nov. are described and illustrated. Two keys to distinguish the Chinese species of the genus are given.

The genus Anufrievia Dworakowska, 1970 is widely distributed in China, Korea, South Korea, Japan, Nepal, India, Thailand, Vietnam and Vietnam. This work reports on two new species of Anufrievia found at Bijie City and Shibing County, Guizhou Province, China.Two new species of the leafhopper genus Anufrievia Dworakowska, 1970 from Guizhou Province China are described and illustrated, i.e., A. crispata sp. nov. and A. confluensa sp. nov. A key to distinguish the Chinese species of the genus is given.

An unusually dark typhlocybine leafhopper (Cicadellidae, Typhlocybinae, Erythroneurini) from Guizhou Province, China, is described as a new genus and species, Shibinga gen. nov., and S. nigra sp. nov. Detailed morphological descriptions and illustrations of the new species are provided.

Abstract Mitogenomes have been widely used to estimate phylogenetic relationships among insects and provide data useful for augmenting traditional morphological characters in delimiting species. Here, complete mitogenome sequences of two closely related typhlocybine leafhoppers, Cassianeura cassiae (Ahmed, 1970) and C. bimaculata Dworakowska, 1984, were obtained and found to be 15,423 bp and 14,597 bp in length, respectively. The gene order was found to be similar to other published leafhopper mitogenomes, but the control region of C. bimaculata is the shortest among known leafhoppers and lacks tandem repeats. Phylogenetic analysis of 13 protein-coding genes (PCGs), the first and second codons of 13 PCGs, 13 PCGs and two rRNAs formed three well-supported tree topologies. The topologies of phylogenetic trees inferred from three datasets were almost identical, which was consistent with previous molecular phylogenies of this group. Comparative morphological study of the ovipositors revealed several characters potentially useful for diagnosing genera and resolving their phylogenetic relationships. Phylogenetic analysis of these and other morphological characters yielded a tree that is mostly consistent with the tree obtained from analysis of mitogenome sequences. In both molecular and morphological phylogenenies, Typhlocybini and Zyginellini clustered into one clade, but neither was recovered as monophyletic.

The number and classification of tribes in the leafhopper subfamily Typhlocybinae are not yet fully clear, and molecular data has recently been used to help resolve the problem. In this study, the mitochondrial genomes of Mitjaevia shibingensis Chen, Song & Webb, 2020 and M. dworakowskae Chen, Song & Webb, 2020 of the tribe Erythroneurini (Cicadellidae, Typhlocybinae) were sequenced. Most protein-coding genes (PCGs) start with ATN and end with TAA or TAG, and the AT content of these three codons were found differ from previous results that show that the first codon has the highest incidence. Two rRNA genes are highly conserved, and the AT content in 16S is higher than that of 12S. The nucleotide diversity and genetic distance among 13 PCGs of the four tribes from Typhlocybinae show that Empoascini nucleotide diversity is significantly less than in the other three tribes, and have the largest distance from the others, while Typhlocybini and Zyginellini have the smallest distance, indicating that the relationship between the two is the closest. The nad2, nad4, nad4L, and nad5 genes have greater nucleotide diversity, showing potential for use as the main markers for species identification. The phylogenetic analysis yielded a well-supported topology with most branches receiving maximum support and a few branches pertaining to relationships within Zyginellini and Typhlocybini receiving lower support. The species of these two tribes are intertwined, and it was impossible to resolve them into separate branches. In addition, the tribes Empoascini and Erythroneurini were recovered as monophyletic, and Alebrini was placed at the base of the tree as the most primitive. These results are broadly in line with other molecular phylogenetical studies which differ from traditional morphological classification.

In karst ecosystems, different geographic environmental conditions can lead to different lithospheric conditions, thus determining community composition and altering biotic interactions. Guizhou Province is a typical ecologically fragile karst area located in the South China Karst. To explore the relationship between biodiversity and environmental changes in different karst habitats, the community structure of typhlocybinae (Hemiptera, Auchenorrhyncha, and Cicadellidae) in three typical karst areas in Guizhou Province (the Zhenfeng–Huajiang Demonstration Zone, the Bijie Salaxi Demonstration Zone, and the Shibing Yuntai Mountain Nature Reserve) was analyzed. These areas are characterized by differences in terms of their geographic environment. For field investigations, typhlocybinae specimens were collected from five common leafhopper host plants—Juglans regia L., Rhus chinensis Mill., Prunus persica (L.) Batsch, Prunus salicina Lindl., and Debregeasia orientalis C.J. Chen—in the three study areas. A total of 4078 typhlocybinae specimens were captured, belonging to 6 tribes, 40 genera, and 121 species. Among them, Alnetoidia dujuanensis, Limassolla lingchuanensis, and Singapora shinshana were the dominant species. The numbers of typhlocybinae specimens from each region were as follows: Shibing, 2170 (53.2%); Bijie, 973 (23.9%); and Huajiang, 935 (22.9%). The number of leafhoppers collected in areas with serious rocky desertification was low, and the number increased with the increase in vegetation coverage. The order of the influence of environmental factors on the community structure of the leafhoppers in the three study areas was Huajiang > Bijie > Shibing. This order is consistent with the ranking of rocky desertification grades in the three study areas. The order based on the number of units at different taxonomic levels was as follows: Bijie (6 tribes, 32 genera, and 68 species) > Huajiang (6 tribes, 22 genera, and 58 species) > Shibing (5 tribes, 21 genera, and 48 species). The results show that environmental factors, such as climate and host plant leaf traits, had various effects on the characteristics and diversity of the leafhopper communities in different grades of rocky desertification areas. This study demonstrates that there are differences in species diversity in different grades of karst rocky desertification areas and provides a theoretical basis for future rocky desertification control and regional ecological restoration.

Camellia tetracocca, a kind of tea with local popularity, is unique to southwest China, where it has an important natural heritage and cultural heritage. However, the tea plant and its sprout are frequently attacked on a large-scale by Empoasca onukii. The metabolic mechanisms of the unique plant for defending against these pest insects are unclear. Therefore, we used untargeted gas chromatography–mass spectrometry (GC-MS) and high performance liquid chromatography–mass spectrometry (LC-MS) to compare the metabolite profiles between E. onukii-attacked leaves and healthy leaves. Using GC-MS, 56 metabolites (24 up-regulated, 32 down-regulated) were preliminarily identified. Additionally, 576 metabolites (280 up-regulated, 287 down-regulated) were rudimentarily identified with LC-MS. Differentially abundant metabolites were mainly enriched in the biosynthesis of specialized metabolites. Fourteen accumulated specialized metabolites are related to insect resistance. Mainly, momordicin I and arabidopside B are reportedly involved in the resistance to the insect. Therefore, we conjectured that the accumulation of momordicin I and arabidopside B is involved in the C. tetracocca’s resistance to E. onukii. Our results indicate that these specialized metabolites may be served as candidate biocontrol agents against the pest of E. onukii of C. tetracocca located in the State-owned Pubai Forest Farm.

In the present paper, two new species of the leafhopper genus Mitjaevia Dworakowska, 1970 from Guizhou Province China are described and illustrated, i.e., Mitjaevia shibingensis sp. nov. and Mitjaevia dworakowskae sp. nov. A checklist to species of the genus and a key to distinguish the Chinese species of the genus are given and the female valvulae are described and figured for the first time.

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are components of bacterial membranes in terrestrial soils, which are widely used in paleoenvironmental reconstruction in global terrestrial soils and marine sediments. In marine sediments, the mixed sources of brGDGTs complicate the applications of brGDGT-related indicators in reconstructing terrestrial environments. In this study, we reported the spatial distribution of brGDGT-related indicators (MBTʹ 5ME, CBTʹ 5ME, #Ringstetra, and IIIa/IIa) in surface sediments from the East China Sea (ECS). MBTʹ 5ME and CBTʹ 5ME showed a stepped trend from the inner shelf to the outer shelf, and #Ringstetra and ∑IIIa/∑IIa values in sediments of the ECS are distinct compared with those in the catchment soils, suggesting marine in situ production of brGDGTs. We also examined the existence of marine in situ brGDGTs and quantitatively determined the contributions of terrestrial and in situ production of brGDGTs. This study reported mixed sources of soil-derived brGDGTs were dominant, and marine in situ brGDGTs were overprinted. Our results indicate that there were predominantly marine in situ brGDGTs (avg. 60.5 ± 5.5%) in the outer shelf due to the weak riverine transportation and were characterized by high #Ringstetra and IIIa/IIa.

Background The hemipteran insect family Cicadellidae (leafhoppers) includes >2,600 valid genera and >22,000 valid species worldwide, including >2,000 species in China. Typhlocybinae, second largest subfamilies of Cicadellidae, is widely distributed in the six major zoogeographic regions of the world, including >4,000 species worldwide and >1,000 species in China. Previously, morphological analysis are often effective to the way of taxonomy, but it did not combine with molecular biology. Therefore, morphology and mitochondrial genomes (mitogenomes) of two leafhopper species, Eupteryx (Eupteryx) minuscula Lindberg, 1929 and Eupteryx (Stacla) gracilirama Hou, Zhang & Huang, 2016 were studied and analyzed. This study analyzed the morphological and molecular characteristics of the two leafhoppers, and showed whether the results of the two identifications were consistent. Methods Based on the method of comparison, mitogenomes and morphology were analyzed to prove the relationship between the two leafhoppers. Results Although two focal species are classified in two different subgenera of the same genus, they still share many morphological features, such as the moderately produced crown fore margin; the milky yellow apical part of scutellum; the pronotum, basal triangles of scutellum, and forewing are dark with several colorless patches on the surface; the light yellow face, without any spots or stripes, and so on. The circular mitogenomes are 16,944 bp long in E. minuscula (GenBank: MN910279) and 17,173 bp long in E. gracilirama (GenBank: MT594485). All of the protein-coding genes are starting with ATN, except for some in mitogenome, which has a single T or TAN as a stop codon. All tRNAs have the typical cloverleaf-shaped structure except for trnS1 (AGN) (E. minuscula) which has a reduced DHU arm. Moreover, these two mitogenomes have trnR with an unpaired base in the acceptor stem. The phylogenetic relationships between E. minuscula and E. gracilirama in respect to related lineages were reconstructed using Maximum likelihood and Maximum parsimony analyses. Discussion The result showed that the tribe Typhlocybini is a sister to the tribes Erythroneurini and Empoascini, and five genera, Bolanusoides, Typhlocyba, Eupteryx, Zyginella and Limassolla are forming a single clade. E. minuscula and E. gracilirama are clustered together, supporting the monophyly of the genus Eupteryx. The above conclusions are consistent with the traditional classification of the subfamily.

The stable and radioactive isotopes (δ13C, Δ14C and δ2H) of black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) in the sediment from the western coastal areas of the Yellow Sea (i.e. the Jiangsu coastal areas (JCA)) were examined to identify the sources these environmental pollutants in the JCA. The results presented that the spatial heterogeneous characteristics of BC and PAHs were markedly presented in the JCA. This was suggestive of presence of the contributions of multiple potential environmental pollution sources. This can be solved and decoupled by applying the Bayesian mode. Accordingly, the statistical model showed that the major environmental pollution contributions is considered as coal combustion (39%) in the JCA. The liquid fossil fuels, petrogenic sources, and biomass combustion were accounted for 27%, 19%, and 15% in the JCA, respectively. The stable and radioactive carbon isotopic ratios (δ13C and Δ14C) of BC collected from the JCA are also applied to discriminate quantitatively the source of contamination. It is demonstrated that the BC in this study originates mainly from combustion of fossil fuels. And rock-derived BC as well as C3 and C4 plants combustions are also numerically predominant for BC and PAHs pollution in the coastal area. It is implied that the environmental PAHs and BC in the JCA seem to origin relatively homologies sources. Furthermore, it is suggested that the stable and radioactive carbon isotopes as well as hydrogen isotopes may be powerful and useful method to source apportionment, and have much advantages to clarify quantitatively BC and PAH pollutions in the coastal environment, but also detailed insights into the source apportionment and fate of the organic carbon in the marginal sea.

A new genus of the leafhopper tribe Erythroneurini (Cicadellidae, Typhlocybinae) from Thailand, Undulivena gen. n., and a new species Undulivena thaiensis sp. n., are described and illustrated. The new genus exhibits a unique feature of the forewing venation with CuA vein strongly sinuate.

Complete mitochondrial genome sequences facilitate species identification and analyses of phylogenetic relationships. However, the available data are limited to the diverse and widespread insect family Cicadellidae. This study analyzes and summarizes the complete mitochondrial genome structure characteristics of 11 leafhopper subfamilies and two newly sequenced Typhlocybinae species, Empoascanara wengangensis and E. gracilis. Moreover, using 13PCGs and rRNA data to analyze the nucleotide diversity, evolution rate, and the phylogenetic relationship between the subfamilies of 56 species, verifying the taxonomic status analysis of E. wengangensis and E. gracilis. The analysis results show that the genome structures of the subfamilies and the newly sequenced two species are very similar, and the size of the CR region is significantly related to the repeat unit. However, in the entire AT-skews and CG-skews, the AT-skews of other subfamilies are all positive, and CG-skews are negative, while Empoascini of Typhlocybinae and Ledrinae are the opposite. Furthermore, among 13PCGs, the AT-skews of 13 species are all negative while CG-skews are positive, which from Empoascini in Typhlocybinae, Idiocerinae, Cicadellinae, Ledrinae, and Evacanthinae. Phylogenetic analysis shows that ML and PB analysis produce almost consistent topologies between different data sets and models, and some relationships are highly supported and remain unchanged. Mileewinae is a monophyletic group and is a sister group with Typhlocybinae, and the sister group of Evacanthinae is Ledrinae + Cicadellinae. Phylogenetic analysis grouped the two newly sequenced species with other species of Typhlocybinae, which was separated from other subfamilies, and all Erythroneurini insects gathered together. However, E. gracilis grouped into a single group, not grouped with species of the same genus (Empoascanara). This result does not match the traditional classification, and other nuclear genes or transcriptome genes may be needed to verify the result. Nucleotide diversity analysis shows that nad4 and nad5 may be evaluated as potential DNA markers defining the Cicadellidae insect species.

Karst rocky desertification is one of the main causes of habitat fragmentation in Southwest China. Guizhou Province is located in the center of the karst area in southern China and is a typical karst ecological environment fragile area. Many studies have shown that habitat fragmentation is the main factor leading to the loss of biodiversity and species extinction, and it is also one of the important factors that threaten the survival of natural organisms. This study initially explored the habitat fragmentation degree, species diversity, and genetic diversity of leafhoppers in three typical karst areas in Guizhou. The study was combined with the general situation of the study area, understanding the main factors affecting habitat fragmentation, and putting forward reasonable protection suggestions for species resources. Based on satellite imagery, field survey collection, molecular sequencing data, and related index measurement methods, we measured the habitat fragmentation degree, species diversity index, and genetic diversity index of Erythroneurine leafhoppers of Shibing Yuntai Mountain Nature Reserve, Bijie Salaxi Demonstration Zone, Zhenfeng-Huajiang Demonstration Zone. Moreover, we compared the differences in the three study areas, carried out correlation analysis with relevant environmental factors, and discussed the main factors that formed the results. The results of the study show that the species diversity and genetic diversity of Erythroneurine leafhoppers in the study areas are affected by habitat fragmentation, and the weaker the degree of habitat fragmentation in the region, the higher the species diversity and genetic diversity, which is specifically manifested in species, quantity, and gene-flow. Understanding the status of biodiversity in karst areas is conducive to the sustainable development of biological resources. In order to better protect the diversity of such insects and their host plants and other biological diversity, combined with the background of the research area, we propose corresponding protection measures for reference.

General characteristics of Gladkara Dworakowska and a checklist to all the known species of this genus are provided. A new species Gladkara klongensis Song & Dietrich, sp. n. from Thailand is added.

In this study, the complete mitochondrial genome of the leafhopper species Empoascanara dwalata (Hemiptera: Cicadellidae: Typhlocybinae) was sequenced and annotated, and the sequence is available in the GenBank with accession number: MT350235. The circular mitogenome with 15,271 bp in length, including 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one AT-rich region. The nucleotide composition is as follows: A (41.7%), T (34.7%), G (10.6%), and C (13.0%). 11 PCGs have ATN as the start codon, except for atp8 and nad5 genes have TTG. The conventional termination codons (TAA or TAG) occur in 11 PCGs, while cox2 and nad5 use incomplete codon (T––) as termination codon. Phylogenetic analysis using 13 PCGs showed that E. dwalata was clustered with three other Typhlocybine species, which was consistent with the conventional classification.

The complete mitochondrial genome of the leafhopper species Eupteryx (Stacla) minusula (Hemiptera: Cicadellidae: Typhlocybinae) are sequenced and annotated. The mitochondrial genome is 16945 bp, and nucleotide composition of the whole mitogenome is highly A + T biased (A: 43.6%; T: 35.2%, G: 11.3%, C: 9.9%). 11 PCGs have ATN as the start codon, except for atp8 and nad5 genes have TTG. The conventional termination codons (TAA or TAG) occur in 11 PCGs, while cox2 and nad5 uses incomplete codon (T) as termination codon. The complete mitogenome sequence of Eupteryx (Stacla) minusula is available in the GenBank with accession number: MN910279.

The complete mitochondrial genome of the leafhopper Parathailocyba orla (Dworakowska, ) was sequenced and annotated in this study. The mitochondrial genome is 15,382 bp long, and nucleotide composition of the whole mitogenome is highly A + T biased (A: 45.8%, T: 33.3%, G: 8.6%, C: 12.3%). 12 PCGs have ATN as the start codon, except for atp8 gene uses TTG. All protein-coding genes used TAA as stop codon, except for nad5, cox2 and cox3, which use incomplete T–– as stop codon. Phylogenetic analysis using 13 PCGs showed that P. orla was clustered with three Typhlocybinae species, which was consistent with the conventional classification.

The complete mitochondrial genome of the leafhopper species Paraahimia luodianensis was sequenced and annotated. It is 16,497 bp in length and consists of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two rRNA genes, and one AT-rich region. Most of PCGs started with ATN and stopped with TAA, except for ATP8 started with TTG, COX2, COX3, NAD5, and NAD1 used incomplete T–– as a stop codon. We constructed a phylogenetic tree from 12 species (Hemiptera) based on neighbour-joining method and using 13 mitochondrial protein-coding genes. The result showed that both species of Limassolla lingchuanensis and P. luodianensis which belonging to Zyginellini were clustered into one clade. This study further enriched mitogenome database of the tribe Zyginellini.

The complete mitochondrial genome of the leafhopper Limassolla lingchuanensis was determined. It is 15,716 bp in length and consists of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 rRNA genes, and a putative control region. ATN and TTG were initiation codons, and TAA, TAG, and T were termination codons. The phylogenetic relationships based on the neighbor-joining method were revealed using 13 PCGs with 10 leafhopper species of family Cicadellidae, which agree with the conventional taxonomy.

The complete mitogenome of Mitjaevia protuberanta (GenBank accession number MN627216) is 14,032 bp (AT: 77.43%) in length, including 13 protein-coding, 22 transfer RNAs, and 2 ribosomal RNAs. All protein-coding genes used ATN as initiation codon except ND5 that used TTG as initiation codon, and TAA, TAG, and T were termination codons. We constructed a phylogenetic tree from 14 species (Hemiptera) based on the nucleotide sequence of 13 mitochondrial protein-coding genes. The phylogenetic analysis results showed that mitochondrial genome of M. protuberanta had the same characteristics as other Cicadellidae species.

The complete mitochondrial genome of the leafhopper Empoascanara sipra Dworakowska, 1980 was sequenced and annotated from this study. The circular molecule is 14,827 bp in length, including 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one AT-rich region. The base composition of the genome is as follows: A (42.6%), T (33.9%), G (10.0%), and C (13.4%). 11 PCGs have ATN as the start codon, except for atp8 and nad5 genes have TTG. The conventional termination codons (TAA or TAG) occur in 11 PCGs, whereas cox2 and nad2 use incomplete codon (T––) as termination codon. Phylogenetic analysis using 13 PCGs showed that E. sipra was clustered with two Typhlocybinae species, which was consistent with the conventional classification.

The complete mitogenome of Evacanthus acuminatus was described in this study. The circular molecule is 14,793 bp in length (GenBank accession no. MK948205), and contains 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an A + T-rich region. The base composition values were A (40.0%), C (11.2%), G (10.0%), and T (38.8%), with an A + T bias (78.8%). ATT, ATG, ATA, TTG were initiation codons and TAA, TAG, T were termination codons. Phylogenetic tree based on concatenated amino acid sequences of 13 PCGs shows that E. acuminatu and Idiocerinae clade form sister groups, and all species of different subfamilies congregate with each other, which is consistent with the traditional taxonomy.

The complete mitochondrial genome of the leafhopper Chlorotettix nigromaculatus was described in this study. The circular molecule is 15,011 bp in length (GenBank accession no. MK234840), consisted of 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and a putative control region. The base composition values for the mitogenome were 42.4, 13.3, 10.4, and 33.9% for A, C, G, and T, respectively. All the 22 tRNAs have the typical cloverleaf structures, except for trnS1 which lacked the dihydrouridine arm. All the 13 PCGs initiated with ATN codons and most of them terminated with TAG or TAA codons, whereas cox2, nad1, and nad4 used a single T residue. The rrnL and rrnS genes were 1220 and 745 bp in length, respectively. Phylogenetic analysis using amino acid sequences of 13 PCGs showed that C. nigromaculatus was clustered with six Deltocephalinae species, which was consistent with the conventional classification.

In the present paper, four new species, Kapsa acuminata, K. quadrispina, K. puerensis and K. yanheensis spp. n. from southwest China are described and illustrated, and a key to the species recorded from China is provided.

Seriana menglaensis sp. n. (Hemiptera: Cicadellidae: Typhlocybinae: Erythroneurini) is described and illustrated from Southwest China. S. equata (Singh, 1969) is recorded for the first time from China.

A new species, Zyginella menghaiensis sp. n. (Hemiptera: Cicadellidae: Typhlocybinae: Zyginellini), is described from China and a key to species of Zyginella from China is provided.

In the present paper, a new species is added to the genus Diomma Motschulsky (Hemiptera: Cicadellidae: Typhlocybinae) from Southwest China, D. pincersa sp. n. At the same time, a key can distinguish all Chinese species of the genus is provided.

In the present paper, three new species are added to the genus Tautoneura Anufriev from China, T. baiyunshana sp. n., T. caoi sp. n. and T. yunnanensis sp. n. A key to species recorded from China is provided.