Insects

27 pages, 14058 KiB

Open AccessArticle

Sinoagetopanorpidae fam. nov., a New Family of Scorpionflies (Insecta, Mecoptera) from the Guadalupian of South China

by Xinneng Lian, Chenyang Cai and Diying Huang

Insects 2023, 14(1), 96; https://doi.org/10.3390/insects14010096 - 16 Jan 2023

Cited by 1 | Viewed by 2406

Mecoptera was in great abundance in the Permian, but little is known from China. A new family, Sinoagetopanorpidae fam. nov., is described and illustrated from the upper Guadalupian Yinping Formation at Yinping Mountain, Chaohu City, Anhui Province, China. Sinoagetopaorpa permiana Lin, Nel and [...] Read more.

Mecoptera was in great abundance in the Permian, but little is known from China. A new family, Sinoagetopanorpidae fam. nov., is described and illustrated from the upper Guadalupian Yinping Formation at Yinping Mountain, Chaohu City, Anhui Province, China. Sinoagetopaorpa permiana Lin, Nel and Huang, 2010 was previously attributed to Permochoristidae and now is revised as the type species of Sinoagetopanorpidae fam. nov. Three genera (two new genera) and ten new species of this new family are described and illustrated: Sinoagetopanorpa permiana Lin, Nel and Huang, 2010, S. nigra sp. nov., S. rotunda sp. nov., S. lini sp. nov., S. minuta sp. nov., S. elegans sp. nov., S. grimaldii sp. nov., S. magna sp. nov., Raragetopanorpa zhangi gen. et sp. nov., Permoagetopanorpa yinpingensis gen. et sp. nov. and P. incompleta sp. nov. Some isolated hind wings are described and illustrated, although it is difficult to assign them to any particular species. As a dominant mecopteran lineage in the Yinping Formation, Sinoagetopanorpidae represents an endemic group that might have independently evolved on the Yangtze Platform. Full article

(This article belongs to the Special Issue Fossil Insects: From Carboniferous to Quaternary)

► Show Figures

Figure 1

21 pages, 2309 KiB

Open AccessEditor’s ChoiceArticle

Precision Monitoring of Honey Bee (Hymenoptera: Apidae) Activity and Pollen Diversity during Pollination to Evaluate Colony Health

by Aimee C. McKinnon, Luke Collins, Jennifer L. Wood, Nick Murphy, Ashley E. Franks and Martin J. Steinbauer

Insects 2023, 14(1), 95; https://doi.org/10.3390/insects14010095 - 16 Jan 2023

Cited by 2 | Viewed by 3419

Abstract

Certain crops depend upon pollination services for fruit set, and, of these, almonds are of high value for Australia. Stressors, such as diseases, parasites, pesticides, and nutrition, can contribute to honey bee Apis mellifera L. colony decline, thereby reducing bee activity and pollination [...] Read more.

Certain crops depend upon pollination services for fruit set, and, of these, almonds are of high value for Australia. Stressors, such as diseases, parasites, pesticides, and nutrition, can contribute to honey bee Apis mellifera L. colony decline, thereby reducing bee activity and pollination efficiency. In Australia, field studies are required to monitor honey bee health and to ascertain whether factors associated with colony decline are impacting hives. We monitored honey bee colonies during and after pollination services of almond. Video surveillance technology was used to quantify bee activity, and bee-collected pollen was periodically tested for pesticide residues. Plant species diversity was also assessed using DNA metabarcoding of the pollen. Results showed that bee activity increased in almond but not in bushland. Residues detected included four fungicides, although the quantities were of low risk of oral toxicity to bees. Floral diversity was lower in the pollen collected by bees from almonds compared to bushland. However, diversity was higher at the onset and conclusion of the almond bloom, suggesting that bees foraged more widely when availability was low. Our findings suggest that commercial almond orchards may sustain healthier bee colonies compared to bushland in early spring, although the magnitude of the benefit is likely landscape-dependent. Full article

(This article belongs to the Section Insect Societies and Sociality)

► Show Figures

Figure 1

18 pages, 4985 KiB

Open AccessArticle

Improvement in the Identification Technology for Asian Spongy Moth, Lymantria dispar Linnaeus, 1758 (Lepidoptera: Erebidae) Based on SS-COI

by Wenzhuai Ji, Fengrui Dou, Chunhua Zhang, Yuqian Xiao, Wenqi Yin, Jinyong Yu, D. K. Kurenshchikov, Xiue Zhu and Juan Shi

Insects 2023, 14(1), 94; https://doi.org/10.3390/insects14010094 - 16 Jan 2023

Cited by 1 | Viewed by 3115

Abstract

Lymantria dispar (Linnaeus, 1758), which is commonly known as spongy moth, with two subspecies, is found in Asia: Lymantria dispar asiatica and Lymantria dispar japonica, collectively referred to as the Asian spongy moth (ASM). The subspecies Lymantria dispar dispar occurs in Europe [...] Read more.

Lymantria dispar (Linnaeus, 1758), which is commonly known as spongy moth, with two subspecies, is found in Asia: Lymantria dispar asiatica and Lymantria dispar japonica, collectively referred to as the Asian spongy moth (ASM). The subspecies Lymantria dispar dispar occurs in Europe and is commonly known as the European spongy moth (ESM). The ASM is on the quarantine list of many countries because it induces greater economic losses than the ESM. Accurate identification is essential to prevent the invasion of ASM into new areas. Although several techniques for identifying ASMs have been developed, the recent discovery of complex patterns of genetic variation among ASMs in China as well as new subspecies in some areas has necessitated the development of new, improved identification techniques, as previously developed techniques are unable to accurately identify ASMs from all regions in China. Here, we demonstrate the efficacy of an improved technique for the identification of the ASM using ASM-specific primers, which were designed based on cytochrome oxidase I sequences from samples obtained from all sites where ASMs have been documented to occur in China. We show that these primers are effective for identifying a single ASM at all life stages and from all ASM populations in China, and the minimum detectable concentration of genomic DNA was 30 pg. The inclusion of other Lymantria samples in our analysis confirmed the high specificity of the primers. Our improved technique allows the spread of ASMs to be monitored in real time and will help mitigate the spread of ASMs to other areas. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

► Show Figures

Figure 1

17 pages, 317 KiB

Open AccessArticle

Impact of Post-Harvest Management Practices in Corn (Zea mays L.) Fields on Arthropods in Subsequent Soybean (Glycine max [L.] Merr.) Plantings

by Alan W. Leslie, Scott R. McCluen and Cerruti R. R. Hooks

Insects 2023, 14(1), 93; https://doi.org/10.3390/insects14010093 - 15 Jan 2023

Viewed by 2462

Abstract

There is increased adoption of cover cropping and conservation tillage in the USA. Many farmers view these practices as methods for improving their soils. However, different cover cropping and tillage practices conducted post-harvest can have a disparate impact on arthropods within the subsequent [...] Read more.

There is increased adoption of cover cropping and conservation tillage in the USA. Many farmers view these practices as methods for improving their soils. However, different cover cropping and tillage practices conducted post-harvest can have a disparate impact on arthropods within the subsequent cash crop. Field experiments were conducted during 2017 and 2018 at two experimental sites to examine the influences of different post-harvest practices following corn (Zea mays L.) harvest on pests and beneficials in subsequent soybean [Glycine max (L.) Merr.] plantings. Experimental treatments included: (1) tillage via chisel plow (CP), (2) no-tillage in which corn residue/stubble remained on the soil surface (CS), and (3) planting a cover crop into corn residue (CC) following corn harvest. Overall, insect herbivore abundance was greater in the CP treatment. Foliar predator numbers were similar among treatments or of greater abundance in CP. The activity density of epigeal insect predators varied according to site and feeding guild. However, spider activity density was greatest in CP. Stink bug egg mortality due to predation and parasitism varied among treatments. However, the percentage of stink bug eggs that hatched was greatest in the CC during both years. Findings suggest that post-harvest practices investigated during this study will have a similar influence on most epigeal and foliar arthropods in soybean. Full article

(This article belongs to the Special Issue Insects Ecology and Biocontrol Applications)

15 pages, 1896 KiB

Open AccessArticle

Suitability of Raycell MK2 Blood X-ray Irradiator for the Use in the Sterile Insect Technique: Dose Response in Fruit Flies, Tsetse Flies and Mosquitoes

by Hanano Yamada, Bénéwendé Aristide Kaboré, Nanwintoum Séverin Bimbilé Somda, Nonhlanhla L. Ntoyi, Chantel Janet de Beer, Jérémy Bouyer, Carlos Caceres, Robert L. Mach and Yeudiel Gómez-Simuta

Insects 2023, 14(1), 92; https://doi.org/10.3390/insects14010092 - 15 Jan 2023

Cited by 7 | Viewed by 3366

Abstract

The sterile insect technique (SIT) is based on the inundatory field release of a target pest following their reproductive sterilization via exposure to radiation. Until recently, gamma irradiation from isotopic sources has been the most widely used in SIT programs. As isotopic sources [...] Read more.

The sterile insect technique (SIT) is based on the inundatory field release of a target pest following their reproductive sterilization via exposure to radiation. Until recently, gamma irradiation from isotopic sources has been the most widely used in SIT programs. As isotopic sources are becoming increasingly expensive, especially for small programs, and regulations surrounding their procurement and shipment increasingly strict, irradiation capacity is one of the limiting factors in smaller or newly developing SIT projects. For this reason, the possibility of using X-ray irradiators has been evaluated in the recent decade. The availability of “off-the-shelf” blood X-ray irradiators that meet the technical requirements for insect irradiation can provide irradiation capacity for those SIT projects in which the acquisition of gamma ray irradiators is not feasible. Following the recent technical characterization of a Raycell MK2 X-ray blood irradiator, it was found in this study, that MK2 instruments were suitable for the sterilization of fruit flies, tsetse flies and mosquitoes, inducing comparable, even slightly higher, sterility levels compared to those achieved by gamma ray irradiation. This, together with its estimated processing efficiency, shows that MK2 irradiators are suitable for small- to mid-sized SIT programs. Full article

(This article belongs to the Special Issue Combining Biological Control and Sterile Insect Technique to Enhance Invasive Pest Species Management)

► Show Figures

Graphical abstract

11 pages, 592 KiB

Open AccessArticle

Entomopathogenic Action of Wild Fungal Strains against Stored Product Beetle Pests

by Spiridon Mantzoukas, Ioannis Lagogiannis, Foteini Kitsiou and Panagiotis A. Eliopoulos

Insects 2023, 14(1), 91; https://doi.org/10.3390/insects14010091 - 14 Jan 2023

Cited by 7 | Viewed by 2400

Abstract

There is ample evidence that entomopathogenic fungi can be used as alternative biological control agents for the management of insect pests in storage facilities. As the market demands more environmentally friendly methods and chemical insecticides become increasingly obsolete, more studies are being conducted [...] Read more.

There is ample evidence that entomopathogenic fungi can be used as alternative biological control agents for the management of insect pests in storage facilities. As the market demands more environmentally friendly methods and chemical insecticides become increasingly obsolete, more studies are being conducted to evaluate new strains of entomopathogenic fungi for their efficacy in storage facilities. In this context, we tested ten species of fungi isolated from soil, belonging to the genera Cladosporium, Condenascus, Lecanicillium, and Penicillium, for their long-term effects on economically important beetle species. Whole wheat was directly sprayed with a conidial suspension of 10⁸ spores/Ml of each of the tested fungi and then adults of Sitophilus granarius, S. oryzae, S. zeamais, Rhyzopertha dominica, and Trogoderma granarium were placed on the sprayed medium to study the mortality effects. Significantly higher mortality than the control was observed in all treatments. The lowest LT₅₀ (9.164 days) was observed in T. granarium infected with Penicillium goetzii. The isolate with the strongest results was L. dimorphum, which recorded remarkably low LT₅₀ values in S. oryzae (~11 days), R. dominica (~12 days), T. granarium (~10 days), and S. granarius (~13 days). However, for S. zeamais, it was more than 16 days. Our results confirm the existing literature on the efficacy of EPF on storage beetles, suggest the possible virulence of wild untested strains, and also highlight the importance of EPF specificity. Full article

(This article belongs to the Collection Integrated Management and Impact of Stored-Product Pests)

► Show Figures

Figure 1

10 pages, 12658 KiB

Open AccessCommunication

Evidence of Seasonal Variation in Body Color in Adults of the Parasitoid Cirrospilus pictus (Hymenoptera: Eulophidae) in Sicily, Italy

by Mirella Lo Pinto, Salvatore Guarino and Alfonso Agrò

Insects 2023, 14(1), 90; https://doi.org/10.3390/insects14010090 - 13 Jan 2023

Cited by 2 | Viewed by 2141

Abstract

As part of the studies on the morphological color variation of insects, a case study on the seasonal body color variation of Cirrospilus pictus (Nees) (Hymenoptera: Eulophidae: Eulophinae) parasitoid of leafminers is reported. Observations were made from January 2000 to December 2003 in [...] Read more.

As part of the studies on the morphological color variation of insects, a case study on the seasonal body color variation of Cirrospilus pictus (Nees) (Hymenoptera: Eulophidae: Eulophinae) parasitoid of leafminers is reported. Observations were made from January 2000 to December 2003 in north-western Sicily (Italy), in relation to sex, body regions of adults and seasonal periods. Wasps parasitizing Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) were collected from organic citrus orchards (Citrus limon L., var. “Femminello zagara bianca” and “Femminello comune”). Adults were grouped in classes: yellow males, black males, yellow females, yellow–black females and black females. The results highlighted a phenotypic pigmentation variation in the head, thorax, gaster and legs of individuals influenced by the season of sampling. Adults were yellow–green in summer months, whereas individuals with dark pigmentation were found in autumn and winter months. A correlation between color patterns and seasonal temperatures was found for both females and males. This work provides a contribution to the description of the intraspecific variability of this species, improving its identification. Full article

(This article belongs to the Special Issue Diversity and Abundance of Predators and Parasitoids of Insect Pests)

► Show Figures

Figure 1

17 pages, 2722 KiB

Open AccessReview

Insect Freeze-Tolerance Downunder: The Microbial Connection

by Mary Morgan-Richards, Craig J. Marshall, Patrick J. Biggs and Steven A. Trewick

Insects 2023, 14(1), 89; https://doi.org/10.3390/insects14010089 - 13 Jan 2023

Cited by 8 | Viewed by 3364

Abstract

Insects that are freeze-tolerant start freezing at high sub-zero temperatures and produce small ice crystals. They do this using ice-nucleating agents that facilitate intercellular ice growth and prevent formation of large crystals where they can damage tissues. In Aotearoa/New Zealand the majority of [...] Read more.

Insects that are freeze-tolerant start freezing at high sub-zero temperatures and produce small ice crystals. They do this using ice-nucleating agents that facilitate intercellular ice growth and prevent formation of large crystals where they can damage tissues. In Aotearoa/New Zealand the majority of cold adapted invertebrates studied survive freezing at any time of year, with ice formation beginning in the rich microbiome of the gut. Some freeze-tolerant insects are known to host symbiotic bacteria and/or fungi that produce ice-nucleating agents and we speculate that gut microbes of many New Zealand insects may provide ice-nucleating active compounds that moderate freezing. We consider too the possibility that evolutionary disparate freeze-tolerant insect species share gut microbes that are a source of ice-nucleating agents and so we describe potential transmission pathways of shared gut fauna. Despite more than 30 years of research into the freeze-tolerant mechanisms of Southern Hemisphere insects, the role of exogenous ice-nucleating agents has been neglected. Key traits of three New Zealand freeze-tolerant lineages are considered in light of the supercooling point (temperature of ice crystal formation) of microbial ice-nucleating particles, the initiation site of freezing, and the implications for invertebrate parasites. We outline approaches that could be used to investigate potential sources of ice-nucleating agents in freeze-tolerant insects and the tools employed to study insect microbiomes. Full article

► Show Figures

Figure 1

15 pages, 1979 KiB

Open AccessArticle

Effects of Different Parts of the Rose Flower on the Development, Fecundity, and Life Parameters of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

by Ding-Yin Li, Dan Zhou, Jun-Rui Zhi, Wen-Bo Yue and Shun-Xin Li

Insects 2023, 14(1), 88; https://doi.org/10.3390/insects14010088 - 13 Jan 2023

Cited by 3 | Viewed by 1890

Abstract

Frankliniella occidentalis (Pergande) is an important horticultural pest that causes serious damage to rose plants, which is one of its preferred foods. In this study, rose petals, rose flowers, and 10% honey solution + kidney bean pods were chosen as foods to assess [...] Read more.

Frankliniella occidentalis (Pergande) is an important horticultural pest that causes serious damage to rose plants, which is one of its preferred foods. In this study, rose petals, rose flowers, and 10% honey solution + kidney bean pods were chosen as foods to assess their influence on the growth, development and fecundity of F. occidentalis. The results showed that developmental time of immature F. occidentalis with the following trend: rose flowers <10% honey solution + kidney bean pods < rose petals < kidney bean pods. The longevities of both female and male adults were lowest when feeding on the rose petals and were highest when feeding on rose flowers. The fecundity was in the following order: rose flowers >10% honey solution + kidney bean pods > rose petals > kidney bean pods. The net reproductive rate (R₀), intrinsic rate of increase (r), and finite rate of increase (λ) of F. occidentalis feeding on rose petals and kidney bean pods were lower than those feeding on rose flowers and 10% honey solution + kidney bean pods. The development, longevity, fecundity, and parameters have significantly changed since F₁ generation after feeding with the three food types. The results indicated that different parts of rose flowers had a significant effect on the development of thrips, and nectar and pollen had a positive effect on thrips population increase and reproduction. Full article

(This article belongs to the Collection Integrated Pest Management of Crop)

► Show Figures

Figure 1

30 pages, 38478 KiB

Open AccessFeature PaperArticle

The Tribe Hyrtanellini Allen, 1980 (Ephemeroptera: Ephemerellidae) of Western and Central Asia with Description of a New Species

by Alexander V. Martynov, Dmitry M. Palatov and Roman J. Godunko

Insects 2023, 14(1), 87; https://doi.org/10.3390/insects14010087 - 13 Jan 2023

Cited by 2 | Viewed by 1874

Abstract

A new species, Serratella leonidi Martynov & Palatov, sp. nov., is described from Tajikistan based on immature stage. Based on larval material from Iran including the topotypes, Serratella elissa Jacobus, Zhou & McCafferty, 2009 is complementary described, and its generic placement is [...] Read more.

A new species, Serratella leonidi Martynov & Palatov, sp. nov., is described from Tajikistan based on immature stage. Based on larval material from Iran including the topotypes, Serratella elissa Jacobus, Zhou & McCafferty, 2009 is complementary described, and its generic placement is clarified. The delimitation of three genera that are members of the tribe Hyrtanellini Allen, 1980, namely Serratella Edmunds, 1959, Torleya Lestage, 1917 and Quatica Jacobus & McCafferty, 2008 is briefly discussed. The phylogenetic reconstruction of Hyrtanellini based on the COI gene showed the relations of representatives of these genera on the one hand, and distinct delimitation of Serratella leonidi sp. nov. and S. elissa on the other. A list of species from Western and Central Asia attributed to Hyrtanellini, their currently known distribution and a key for the determination of the larvae are proposed. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

► Show Figures

Figure 1

12 pages, 2087 KiB

Open AccessCommunication

Adults of Alderflies, Fishflies, and Dobsonflies (Megaloptera) Expel Meconial Fluid When Disturbed

by Pei Yu, Chengquan Cao, Xingyue Liu and Fumio Hayashi

Insects 2023, 14(1), 86; https://doi.org/10.3390/insects14010086 - 13 Jan 2023

Viewed by 1869

Abstract

Chemical secretions are an effective means by which insects may deter potential enemies, already being studied extensively with regard to their chemicals, synthesis, toxicity, and functions. However, these defensive secretions have been little studied in Megaloptera. Herein, the fluid expelling behavior of adult [...] Read more.

Chemical secretions are an effective means by which insects may deter potential enemies, already being studied extensively with regard to their chemicals, synthesis, toxicity, and functions. However, these defensive secretions have been little studied in Megaloptera. Herein, the fluid expelling behavior of adult alderflies (Sialidae), fishflies (Corydalidae: Chauliodinae), and dobsonflies (Corydalidae: Corydalinae), all of the order Megaloptera, is described in detail regarding the timing and possible function of this behavior. When disturbed artificially, both males and females could expel fluid from the anus. However, the frequency of expelling was much lower in alderflies than in fishflies and dobsonflies. The amount of expelled fluid relative to body weight was also smaller in alderflies. In fishflies and dobsonflies, the amount of expelled fluid decreased with adult age, probably because the fluid is little replenished once expelled. The cream-colored fluid seems to be meconial fluid produced via the Malpighian tubules at the pupal stage, which is usually discharged at adult emergence in most other holometabolous insects. However, adult fishflies and dobsonflies often expel it vigorously by bending their abdomen when disturbed after emergence. Thus, the fluid expelling may be an anti-predatory behavior, particularly in younger adults that can expel a relatively large amount of fluid. Full article

(This article belongs to the Special Issue Diversity and Evolution of Lacewings and Allies (Neuropterida))

► Show Figures

Figure 1

25 pages, 6230 KiB

Open AccessArticle

The Complete Mitogenomes of Three Grasshopper Species with Special Notes on the Phylogenetic Positions of Some Related Genera

by Chulin Zhang, Benyong Mao, Hanqiang Wang, Li Dai, Yuan Huang, Zhilin Chen and Jianhua Huang

Insects 2023, 14(1), 85; https://doi.org/10.3390/insects14010085 - 13 Jan 2023

Cited by 4 | Viewed by 2566

Abstract

Clarifying phylogenetic position and reconstructing robust phylogeny of groups using various evidences are an eternal theme for taxonomy and systematics. In this study, the complete mitogenomes of Longzhouacris mirabilis, Ranacris albicornis, and Conophyma zhaosuensis were sequenced using next-generation sequencing (NGS), and the [...] Read more.

Clarifying phylogenetic position and reconstructing robust phylogeny of groups using various evidences are an eternal theme for taxonomy and systematics. In this study, the complete mitogenomes of Longzhouacris mirabilis, Ranacris albicornis, and Conophyma zhaosuensis were sequenced using next-generation sequencing (NGS), and the characteristics of the mitogenomes are presented briefly. The mitogenomes of the three species are all circular molecules with total lengths of 16,164 bp, 15,720 bp, and 16,190 bp, respectively. The gene structures and orders, as well as the characteristics of the mitogenomes, are similar to those of other published mitogenomes in Caelifera. The phylogeny of the main subfamilies of Acrididae with prosternal process was reconstructed using a selected dataset of mitogenome sequences under maximum likelihood (ML) and Bayesian inference (BI) frameworks. The results showed that the genus Emeiacris consistently fell into the subfamily Melanoplinae rather than Oxyinae, and the genus Choroedocus had the closest relationship with Shirackiacris of the subfamily Eyprepocnemidinae in both phylogenetic trees deduced from mitogenome protein coding genes (PCGs). This finding is entirely consistent with the morphological characters, which indicate that Emeiacris belongs to Melanoplinae and Choroedocus belongs to Eyprepocnemidinae. In addition, the genera Conophymacris and Xiangelilacris, as well as Ranacris and Menglacris, are two pairs of the closest relatives, but their phylogenetic positions need further study to clarify. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

► Show Figures

Figure 1

14 pages, 4364 KiB

Open AccessFeature PaperArticle

Constructing an Ensemble Model and Niche Comparison for the Management Planning of Eucalyptus Longhorned Borer Phoracantha semipunctata under Climate Change

by Haoxiang Zhao, Xiaoqing Xian, Te Liang, Fanghao Wan, Juan Shi and Wanxue Liu

Insects 2023, 14(1), 84; https://doi.org/10.3390/insects14010084 - 13 Jan 2023

Cited by 4 | Viewed by 2617

Abstract

Phoracantha semipunctata is a destructive invasive alien forest pest worldwide. It primarily damages the eucalyptus via adults, affecting almost all parts of the eucalyptus. Its larvae develop in almost all major tissues of the plant. Phoracantha semipunctata spreads both via the migration of [...] Read more.

Phoracantha semipunctata is a destructive invasive alien forest pest worldwide. It primarily damages the eucalyptus via adults, affecting almost all parts of the eucalyptus. Its larvae develop in almost all major tissues of the plant. Phoracantha semipunctata spreads both via the migration of adults and global trade in intercontinental translocation. Currently, this pest has spread to six continents worldwide, except Antarctica, resulting in substantial economic losses. Based on global occurrence data and environmental variables, the potential global geographical distribution of P. semipunctata was predicted using an ensemble model. The centroid shift, overlap, unfilling, and expansion scheme were selected to assess niche dynamics during the global invasion process. Our results indicated that the AUC and TSS values of the ensemble model were 0.993 and 0.917, respectively, indicating the high prediction accuracy of the model. The distribution pattern of P. semipunctata is primarily attributed to the temperature seasonality (bio4), mean temperature of the warmest quarter (bio10), and human influence index variables. The potential geographical distribution of P. semipunctata is primarily in western and southwestern Asia, western Europe, western and southern North America, southern South America, southern Africa, and eastern and southern Oceania. The potential geographical distribution of P. semipunctata showed a downward trend in the 2030s and the 2050s. The distribution centroid showed a general tendency to shift southward from the near-current to future climate. Phoracantha semipunctata has largely conserved its niche during the global invasion process. More attention should be paid to the early warning, prevention, and control of P. semipunctata in the countries and regions where it has not yet become invasive. Full article

(This article belongs to the Special Issue Invasive Pest Management and Climate Change)

► Show Figures

Figure 1

18 pages, 4764 KiB

Open AccessArticle

Orthopteran Diversity in Steep Slope Vineyards: The Role of Vineyard Type and Vegetation Management

by Vera Wersebeckmann, Carolin Biegerl, Ilona Leyer and Karsten Mody

Insects 2023, 14(1), 83; https://doi.org/10.3390/insects14010083 - 13 Jan 2023

Cited by 7 | Viewed by 1996

Abstract

The abandonment of traditional agricultural practices and subsequent succession are major threats to many open-adapted species and species-rich ecosystems. Viticulture on steep slopes has recently suffered from strong declines due to insufficient profitability, thus increasing the area of fallow land considerably. Changing cultivation [...] Read more.

The abandonment of traditional agricultural practices and subsequent succession are major threats to many open-adapted species and species-rich ecosystems. Viticulture on steep slopes has recently suffered from strong declines due to insufficient profitability, thus increasing the area of fallow land considerably. Changing cultivation systems from vertically oriented to modern vineyard terraces offers an opportunity to maintain management economically viable and thus reduces further abandonment. Hillside parallel terraces favor mechanization, and their embankments offer large undisturbed areas that could provide valuable habitats. We investigated the effects of vineyard abandonment, different vineyard management types (vertically oriented vs. terraced), and local parameters on Orthoptera diversity in 45 study sites along the Upper Middle Rhine Valley in Germany. Our results show that woody structures and vineyard abandonment reduced Orthoptera diversity at the local and landscape scale due to decreased habitat quality, especially for open-adapted species. In contrast, open inter-rows of actively managed vineyard types supported heat-adapted Caelifera species. On terrace embankments, extensive management and taller vegetation benefited Ensifera species, while short and mulched vegetation in vertically oriented vineyards favored the dominance of one single Caelifera species. Our results highlight the significance of maintaining viticultural management on steep slopes for the preservation of both open-adapted Orthoptera species and the cultural landscape. Full article

(This article belongs to the Section Insect Ecology, Diversity and Conservation)

► Show Figures

Figure 1

14 pages, 1240 KiB

Open AccessArticle

Influence of Temperature, Photoperiod, and Supplementary Nutrition on the Development and Reproduction of Scutellista caerulea Fonscolombe (Hymenoptera: Pteromalidae)

by Xian Li, Zhengpei Ye, Junyu Chen, Junhong Zhu, Dongyin Han, Jianyun Wang, Lei Li, Yueguan Fu and Fangping Zhang

Insects 2023, 14(1), 82; https://doi.org/10.3390/insects14010082 - 13 Jan 2023

Cited by 1 | Viewed by 1830

Abstract

Scutellista ciruela Fonscolombe has a significant controlling effect on the rubber tree pest, Parasaissetia nigra Nietner. To identify the optimal conditions for the population growth of S. caerulea, we assessed how temperature, photoperiod, and supplementary nutrition affected its development and reproduction. The [...] Read more.

Scutellista ciruela Fonscolombe has a significant controlling effect on the rubber tree pest, Parasaissetia nigra Nietner. To identify the optimal conditions for the population growth of S. caerulea, we assessed how temperature, photoperiod, and supplementary nutrition affected its development and reproduction. The results demonstrated that the number of eggs laid and parasitism rates of S. caerulea were the highest at 33 °C. The developmental rate of S. caerulea was the fastest and the number of emerged adults the highest. The number of eggs laid and the parasitism rates increased when the light duration increased within a day. Females did not lay any eggs when the whole day was dark. At a photoperiod of 14:10 (L:D), the developmental duration was the shortest and the number of emerged adults was the highest. Adult life span was the longest under a 12:12 (L:D) photoperiod. During the adult stage, supplementary nutrition, such as sucrose, fructose, honey, and glucose, increased the life span of S. caerulea. The life span of S. caerulea was longer when provided with a supplementary diet of sucrose or honey, compared to other tested diets. The results suggested that the most suitable conditions for S. caerulea’s population growth were the following: 30 to 33 °C, with 12 to 14 h of daylight, and the provision of sucrose or honey as supplemental diet for the adults. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

12 pages, 1541 KiB

Open AccessFeature PaperArticle

Intraguild Predation of Hippodamia variegata on Aphid Mummies in Cotton Field

by Shuying Dou, Bing Liu, Yangtian Liu, Jianping Zhang and Yanhui Lu

Insects 2023, 14(1), 81; https://doi.org/10.3390/insects14010081 - 13 Jan 2023

Cited by 5 | Viewed by 1818

Abstract

Intraguild predation among arthropod predators in agricultural ecosystems may have a negative impact on biological control. At present, there are few direct reports on trophic relationships among participants of predation in field groups. In this study, we measured the feeding choices of Hippodamia [...] Read more.

Intraguild predation among arthropod predators in agricultural ecosystems may have a negative impact on biological control. At present, there are few direct reports on trophic relationships among participants of predation in field groups. In this study, we measured the feeding choices of Hippodamia variegata (Goeze) towards mummies with different densities of Aphis gossypii Glover. The dynamics of the occurrence of mummies in the cotton field were investigated over 2017–2019. Singleplex PCR and multiplex PCR were used to detect the predation of 2090 H. variegata individuals on aphids and mummies in Xinjiang cotton field, which revealed the intraguild predation frequency between H. variegata and various parasitoids. There was no obvious feeding preference of H. variegata towards live aphids or mummies, which mainly depended on the relative density of prey. Among the four species of aphids detected in H. variegata, A. gossypii had a high detection rate and was the main prey source of the ladybeetle in the cotton filed. Mostly, ladybeetles consumed parasitoids through mummies, with 6.39% directly feeding on adult parasitoids. H. variegata had strong trophic links to both parasitoids and aphids. We established a food web of aphids–primary parasitoids–hyperparasitoids–H. variegata, which can be used to evaluate the pest control ability of H. variegata from a new perspective. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

15 pages, 6061 KiB

Open AccessArticle

Presence of Spodoptera frugiperda Multiple Nucleopolyhedrovirus (SfMNPV) Occlusion Bodies in Maize Field Soils of Mesoamerica

by Trevor Williams, Guadalupe del Carmen Melo-Molina, Jaime A. Jiménez-Fernández, Holger Weissenberger, Juan S. Gómez-Díaz, Laura Navarro-de-la-Fuente and Andrew R. Richards

Insects 2023, 14(1), 80; https://doi.org/10.3390/insects14010080 - 13 Jan 2023

Cited by 3 | Viewed by 2583

Abstract

The occlusion bodies (OBs) of lepidopteran nucleopolyhedroviruses can persist in soil for extended periods before being transported back on to the foliage for transmission to the host insect. A sensitive insect bioassay technique was used to detect OBs of Spodoptera frugiperda multiple nucleopolyhedrovirus [...] Read more.

The occlusion bodies (OBs) of lepidopteran nucleopolyhedroviruses can persist in soil for extended periods before being transported back on to the foliage for transmission to the host insect. A sensitive insect bioassay technique was used to detect OBs of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) in 186 soil samples collected from maize fields in the southern Mexican states of Chiapas, Tabasco, Campeche, Yucatán, and Quintana Roo, as well Belize and Guatemala. Overall, 35 (18.8%) samples proved positive for SfMNPV OBs. The frequency of OB-positive samples varied significantly among Mexican states and countries (p < 0.05). Between 1.7 and 4.4% of S. frugiperda larvae that consumed OB-positive samples died from polyhedrosis disease. Restriction endonuclease analysis using PstI and HindIII confirmed that the soil-derived isolates were strains of SfMNPV and that genetic diversity was evident among the isolates. The prevalence of OB-positive soil samples did not differ with altitude or extension (area) of the maize field, but it was significantly higher in fields with the presence of living maize plants compared to those containing dead plants or crop residues (p < 0.05). Georeferenced soil samples were used to identify soil types on digitized soil maps. Lithosol and Luvisol soils had a higher than average prevalence of OB-positive samples (42–45% positive) (p = 0.006), as did Andosol, Gleysol, and Vertisol soils (33–60% OB-positive), although the sample sizes were small (<5 samples) for the latter three soils. In contrast, Cambisol soils had a lower than average prevalence of OB-positive samples (5% positive). Bioassays on Acrisol, Fluvisol, Phaeozem, and Rendzina soils resulted in intermediate levels of OB-positive samples. We conclude that certain soil types may favor OB persistence and virus-mediated biological pest control. The soil is also likely to provide a valuable source of genetic diversity for the design of virus-based insecticides against this pest. Full article

(This article belongs to the Special Issue Targeting Insects: A Focus on Viruses and Toxic Proteins)

► Show Figures

Figure 1

8 pages, 633 KiB

Open AccessArticle

Effects of Flight on Reproductive Development in Long-Winged Female Crickets (Velarifictorus aspersus Walker; Orthoptera: Gryllidae) with Differences in Flight Behavior

by Ye-Song Ren, Bin Zhang, Yang Zeng and Dao-Hong Zhu

Insects 2023, 14(1), 79; https://doi.org/10.3390/insects14010079 - 12 Jan 2023

Viewed by 1822

Abstract

A trade-off between the capacity for flight and reproduction has been documented extensively in wing polymorphic female insects, thereby supporting the possible fitness gain due to flightlessness. However, most of these studies were conducted without considering the effect of flight behavior. In the [...] Read more.

A trade-off between the capacity for flight and reproduction has been documented extensively in wing polymorphic female insects, thereby supporting the possible fitness gain due to flightlessness. However, most of these studies were conducted without considering the effect of flight behavior. In the present study, we assessed the flight duration by long-winged (LW) females in the cricket species Velarifictorus aspersus on different days after adult emergence and examined the effect of flight on ovarian development in LW females with different flight capacities. Our results showed that the flight capacity increased with age and peaked after 5 days. In addition, the flight capacity varied among individuals, where most LW females could only take short flights (sustained flight time < 10 min) and only a few individuals could take long flights (sustained flight time > 20 min). In LW female crickets demonstrating only short flights, repeated flying for 30 or 60 min significantly promoted reproductive development. However, in those capable of long flights, reproductive development was affected only after a flight of 60 min. The flight muscles degraded after the start of rapid reproduction in those with both short and long flights. Our results indicated that the critical flight time for switching from flight to reproduction varies among LW V. aspersus female crickets with polymorphic flight behavior. Full article

(This article belongs to the Section Insect Behavior and Pathology)

► Show Figures

Figure 1

15 pages, 3839 KiB

Open AccessArticle

Evaluation of Modern Techniques for Species Identification of Lutzia Mosquitoes (Diptera: Culicidae) in Thailand: Geometric Morphometrics and DNA Barcoding

by Sedthapong Laojun, Tanasak Changbunjong and Tanawat Chaiphongpachara

Insects 2023, 14(1), 78; https://doi.org/10.3390/insects14010078 - 12 Jan 2023

Cited by 9 | Viewed by 2603

Abstract

There are four species of Lutzia mosquitoes in Thailand, including Lutzia chiangmaiensis, Lt. fuscana, Lt. halifaxii, and Lt. vorax. The accurate species identification of adult Lutzia mosquitoes based on morphological features requires many body parts, including the abdominal terga and [...] Read more.

There are four species of Lutzia mosquitoes in Thailand, including Lutzia chiangmaiensis, Lt. fuscana, Lt. halifaxii, and Lt. vorax. The accurate species identification of adult Lutzia mosquitoes based on morphological features requires many body parts, including the abdominal terga and wing. However, species identification is difficult in the case of damaged specimens when some of their morphological character is missing due to transit or gathering in the field. Thus, we evaluated the efficacy of the landmark-based geometric morphometric (GM) approach for the discrimination of Lutzia species in Thailand. In addition, DNA barcoding was also used in parallel with the GM approach to identify the species. Larvae of Lutzia were collected, raised into adults, and identified based on their morphological characteristics. The validated reclassification test results clearly demonstrated that wing shape resulted in a high level of success in identification (correct identifications ranged from 92.50% to 100%); however, based on the DNA barcoding analyses, our results showed that it was poorly effective in identifying Lt. fuscana and Lt. halifaxii based on an overlap between the intraspecific and interspecific divergence. Moreover, our survey results provide updates on the distribution of Lt. chiangmaiensis and Lt. vorax in Thailand. This research will help medical entomologists more efficiently identify mosquitoes in the genus Lutzia, resulting in more effective mosquito control and surveillance. Full article

(This article belongs to the Special Issue Mosquito: Ecology, Behavior and Molecular Biology)

► Show Figures

Figure 1

10 pages, 749 KiB

Open AccessArticle

Effects of Flupyradifurone and Two Reference Insecticides Commonly Used in Toxicological Studies on the Larval Proteome of the Honey bee Apis mellifera

by Arne Kablau, Silvio Erler, Jakob H. Eckert, Jens Pistorius, Soroush Sharbati and Ralf Einspanier

Insects 2023, 14(1), 77; https://doi.org/10.3390/insects14010077 - 12 Jan 2023

Cited by 3 | Viewed by 2373

Abstract

The western honey bee Apis mellifera is globally distributed due to its beekeeping advantages and plays an important role in the global ecology and economy. In recent decades, several studies have raised concerns about bee decline. Discussed are multiple reasons such as increased [...] Read more.

The western honey bee Apis mellifera is globally distributed due to its beekeeping advantages and plays an important role in the global ecology and economy. In recent decades, several studies have raised concerns about bee decline. Discussed are multiple reasons such as increased pathogen pressure, malnutrition or pesticide use. Insecticides are considered to be one of the major factors. In 2013, the use of three neonicotinoids in the field was prohibited in the EU. Flupyradifurone was introduced as a potential successor; it has a comparable mode of action as the banned neonicotinoids. However, there is a limited number of studies on the effects of sublethal concentrations of flupyradifurone on honey bees. Particularly, the larval physiological response by means of protein expression has not yet been studied. Hence, the larval protein expression was investigated via 2D gel electrophoresis after following a standardised protocol to apply sublethal concentrations of the active substance (flupyradifurone 10 mg/kg diet) to larval food. The treated larvae did not show increased mortality or an aberrant development. Proteome comparisons showed clear differences concerning the larval metabolism, immune response and energy supply. Further field studies are needed to validate the in vitro results at a colony level. Full article

(This article belongs to the Section Insect Societies and Sociality)

► Show Figures

Figure 1

12 pages, 12701 KiB

Open AccessFeature PaperArticle

Selection and Comparative Gene Expression of Midgut-Specific Targets for Drosophila suzukii

by June-Sun Yoon, Seung-Joon Ahn and Man-Yeon Choi

Insects 2023, 14(1), 76; https://doi.org/10.3390/insects14010076 - 12 Jan 2023

Cited by 2 | Viewed by 3455

Abstract

Spotted-wing drosophila (SWD), Drosophila suzukii, is a destructive and invasive pest that attacks most small fruits and cherries. The current management for SWD involves the use of conventional insecticides. In an effort to develop a biologically based control option, the application of [...] Read more.

Spotted-wing drosophila (SWD), Drosophila suzukii, is a destructive and invasive pest that attacks most small fruits and cherries. The current management for SWD involves the use of conventional insecticides. In an effort to develop a biologically based control option, the application of RNA interference (RNAi) has been investigated. To develop an RNAi approach, suitable targets must be identified, and an efficient delivery method must be developed for introducing the double-stranded RNA (dsRNA) in the midgut. In D. suzukii, we previously found that dsRNA nucleases actively degrade dsRNA molecules in the midgut. In this study, we focused on identifying biological targets focused on the midgut membrane. The profile of midgut-specific genes was analyzed and compared with the genes expressed in the whole-body using transcriptome analysis. Differential gene expression analysis revealed that 1921 contigs were upregulated and 1834 contigs were downregulated in the midgut when compared to genes from other body tissues. We chose ten midgut-specifically upregulated genes and empirically confirmed their expressions. We are particularly interested in the midgut membrane proteins, including G protein-coupled receptors (GPCRs) such as diuretic hormone 31 (DH31) receptor, neuropeptide F (NPF) recepror, toll-9, adhesion receptors, methuselah (mth), and gustatory receptor, because insect GPCRs have been offered great potential for next-generation pest management. Full article

(This article belongs to the Special Issue Insect Genome and Transcriptome Data)

► Show Figures

Figure 1

10 pages, 2159 KiB

Open AccessFeature PaperArticle

Fitness Cost of the Field-Evolved Resistance to Sulfoxaflor and Multi-Insecticide Resistance of the Wheat Aphid Sitobion miscanthi (Takahashi)

by Xinan Li, Saige Zhu, Qiuchi Li, Yulin Sun, Yanbo Wang, Xujun Tian, Xiao Ran, Xiangrui Li, Yunhui Zhang, Haifeng Gao and Xun Zhu

Insects 2023, 14(1), 75; https://doi.org/10.3390/insects14010075 - 12 Jan 2023

Cited by 1 | Viewed by 1911

Abstract

Sulfoxaflor belongs to a new class of insecticides that is effective against many sap-feeding pests. In this study on Sitobion miscanthi (Takahashi) (i.e., the predominant wheat pest), a highly sulfoxaflor-resistant (SulR) population was obtained from a field. Its resistance to the other seven [...] Read more.

Sulfoxaflor belongs to a new class of insecticides that is effective against many sap-feeding pests. In this study on Sitobion miscanthi (Takahashi) (i.e., the predominant wheat pest), a highly sulfoxaflor-resistant (SulR) population was obtained from a field. Its resistance to the other seven insecticides and its biological fitness were analyzed using a leaf-dip method and a two-sex life table approach, respectively. Compared with the relatively susceptible (SS) population, the SulR population was highly resistant to sulfoxaflor, with a relative insecticide resistance ratio (RR) of 199.8 and was moderately resistant to beta-cypermethrin (RR = 14.5) and bifenthrin (RR = 42.1) but exhibited low resistance to chlorpyrifos (RR = 5.7). Additionally, the SulR population had a relative fitness of 0.73, with a significantly prolonged developmental period as well as a lower survival rate and poorer reproductive performance than the SS population. In conclusion, our results suggest that S. miscanthi populations that are highly resistant to sulfoxaflor exist in the field. The possibility that insects may develop multi-resistance between sulfoxaflor and pyrethroids is a concern. Furthermore, the high sulfoxaflor resistance of S. miscanthi was accompanied by a considerable fitness cost. The study data may be useful for improving the rational use of insecticides and for exploring novel insecticide resistance mechanisms. Full article

(This article belongs to the Special Issue The Evolution of Pesticide Resistance)

► Show Figures

Figure 1

8 pages, 1063 KiB

Open AccessArticle

Rotation of Multiple Single-Gene Transgenic Crops Did Not Slow the Evolution of Resistance to Cry1F or Cry1Ie in Ostrinia furnacalis

by Yueqin Wang, Yudong Quan, Zhenying Wang and Kanglai He

Insects 2023, 14(1), 74; https://doi.org/10.3390/insects14010074 - 12 Jan 2023

Cited by 1 | Viewed by 1933

Abstract

A common strategy for delaying the evolution of resistance to transgenic crops that produce insecticidal proteins from Bacillus thuringiensis is to ensure that insect pests are exposed to multiple toxins with different mechanisms of action (MoAs). This can take the form of planting [...] Read more.

A common strategy for delaying the evolution of resistance to transgenic crops that produce insecticidal proteins from Bacillus thuringiensis is to ensure that insect pests are exposed to multiple toxins with different mechanisms of action (MoAs). This can take the form of planting crops in a rotation pattern when different crops expressing single toxins are available on the market. The efficacy of a rotation strategy is reliant on mathematical models based on biological assumptions. Here, we designed laboratory evolution experiments to test whether Bt-based insecticidal proteins with different MoAs used in rotation could delay resistance from developing in Asian corn borer (ACB), Ostrinia furnacalis. We investigated the proteins Cry1Ab, Cry1F, and Cry1Ie, which are widely utilized for commercial insect control. We found that rotation of multiple toxins did not slow the evolution of resistance to Cry1F or Cry1Ie. Furthermore, the evolution of ACB to the Cry1Ab toxin develops faster when Cry1F or Cry1Ie is present, as compared to Cry1Ab exposure only. Our results suggest that toxins used in a rotation fashion do not work as an effective strategy in delaying ACB resistance evolution to Cry toxins over one-toxin exposure. Our result highlights the need to better understand the biological factors leading to insecticidal protein resistance and to develop IRM strategies against target insects. Full article

(This article belongs to the Special Issue Resistance of Pests to Insecticidal Proteins from Bacillus thuringiensis (Bt))

► Show Figures

Figure 1

12 pages, 2428 KiB

Open AccessArticle

Investment Trade-Off between Mating Behavior and Tonic Immobility in the Sweetpotato Weevil Cylas formicarius (Coleoptera: Brentidae)

by Haoyong Ouyang, Runzhi Zhang and Muhammad Haseeb

Insects 2023, 14(1), 73; https://doi.org/10.3390/insects14010073 - 12 Jan 2023

Cited by 2 | Viewed by 2525

Abstract

Numerous studies have confirmed that the trade-off between anti-predator behavior and mating behavior occurs in certain insect species. This suggests that insects invest more in anti-predator behavior, and fewer resources or time can be used in mating behavior. However, few studies focus on [...] Read more.

Numerous studies have confirmed that the trade-off between anti-predator behavior and mating behavior occurs in certain insect species. This suggests that insects invest more in anti-predator behavior, and fewer resources or time can be used in mating behavior. However, few studies focus on tonic immobility, an important anti-predator behavior in nature, and different stages in mating behavior. Tonic immobility (TI) is considered to be an important anti-predator behavior. Herein, we investigated the relationship between TI and mating behavior in the sweetpotato weevil (SPW), Cylas formicarius. As the first step, we artificially selected SPWs for the longer duration of TI (L-strain) and the shorter duration of TI (S-strain). The effect of courtship and copulation on the duration of TI in two artificial selection strains was tested. Furthermore, we compared the frequency and duration of two mating behaviors in four kinds of pairs (LF×LM, LF×SM, SF×LM, and SF×SM: LM—L-strain male; SM—S-strain male; LF—L-strain female; SF—S-strain female). Finally, we tested insemination success in four kinds of pairs (male and female SPWs from the L-strain or the S-strain). The courtship and copulation significantly reduced the duration of TI. Pairs with males from the L-strain showed lower frequency and longer duration of courtship than pairs with males from the S-strain. Similarly, males from L-strain pairs showed a longer period of copulation than pairs with males from the S-strain. However, there is no significant difference in the frequency of copulation and the success of insemination. These results support that there was a significant trade-off between TI and courtship as well as copulation in the SPW. Full article

(This article belongs to the Special Issue Management of True Weevils (Curculionidae))

► Show Figures

Figure 1

13 pages, 3269 KiB

Open AccessArticle

An LW-Opsin Mutation Changes the Gene Expression of the Phototransduction Pathway: A Cryptochrome1 Mutation Enhances the Phototaxis of Male Plutella xylostella (Lepidoptera: Plutellidae)

by Shao-Ping Chen, Xiao-Lu Lin, Rong-Zhou Qiu, Mei-Xiang Chi and Guang Yang

Insects 2023, 14(1), 72; https://doi.org/10.3390/insects14010072 - 12 Jan 2023

Cited by 2 | Viewed by 1963

Abstract

Plutella xylostella is a typical phototactic pest. LW-opsin contributes to the phototaxis of P. xylostella, but the expression changes of other genes in the phototransduction pathway caused by the mutation of LW-opsin remain unknown. In the study, the head transcriptomes of male [...] Read more.

Plutella xylostella is a typical phototactic pest. LW-opsin contributes to the phototaxis of P. xylostella, but the expression changes of other genes in the phototransduction pathway caused by the mutation of LW-opsin remain unknown. In the study, the head transcriptomes of male G88 and LW-opsin mutants were compared. A GO-function annotation showed that DEGs mainly belonged to the categories of molecular functions, biological processes, and cell composition. Additionally, a KEGG-pathway analysis suggested that DEGs were significantly enriched in some classical pathways, such as the phototransduction-fly and vitamin digestion and absorption pathways. The mRNA expressions of genes in the phototransduction-fly pathway, such as Gq, ninaC, and rdgC were significantly up-regulated, and trp, trpl, inaD, cry1, ninaA and arr1 were significantly down-regulated. The expression trends of nine DEGs in the phototransduction pathway confirmed by a RT-qPCR were consistent with transcriptomic data. In addition, the influence of a cry1 mutation on the phototaxis of P. xylostella was examined, and the results showed that the male cry1 mutant exhibited higher phototactic rates to UV and blue lights than the male G88. Our results indicated that the LW-opsin mutation changed the expression of genes in the phototransduction pathway, and the mutation of cry1 enhanced the phototaxis of a P. xylostella male, providing a basis for further investigation on the phototransduction pathway in P. xylostella. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

14 pages, 4160 KiB

Open AccessArticle

Morphologic Characters of the Rostrum in Two Weevils, Eucryptorrhynchus scrobiculatus Motschulsky and E. brandti Harold (Coleoptera: Curculionidae: Cryptorrhychinae)

by Ganyu Zhang, Ruihong Sun, Huijuan Li and Junbao Wen

Insects 2023, 14(1), 71; https://doi.org/10.3390/insects14010071 - 11 Jan 2023

Cited by 2 | Viewed by 2320

Abstract

(1) Eucryptorrhynchus scrobiculatus and E. brandti (Coleoptera: Curculionidae: Cryptorrhychinae) are both pests of Ailanthus altissima, found in China. During ovipositing, gravid females of the two weevils need to excavate a cavity in the oviposition substrate with their rostrum, while their oviposition sites [...] Read more.

(1) Eucryptorrhynchus scrobiculatus and E. brandti (Coleoptera: Curculionidae: Cryptorrhychinae) are both pests of Ailanthus altissima, found in China. During ovipositing, gravid females of the two weevils need to excavate a cavity in the oviposition substrate with their rostrum, while their oviposition sites are different. (2) In this study, to explore the boring mechanism of E. scrobiculatus and E. brandti during ovipositing, the morphologic characters of the rostra of two weevils were studied in detail by scanning electron microscopy and micro-CT. (3) Their rostra appear similar, but the rostrum surface of E. scrobiculatus is rougher than that of E. brandti; their fine structures of rostrum and sensilla distribution are similar, but the sensilla twig basiconica 3 is distributed at the apex of labial palpus in E. brandti females, while not at the apex of labial palpus in E. scrobiculatus females; their rostra are hollow and their cuticle thickness is constantly changing, but the proportion of the whole rostrum tube cuticle in E. scrobiculatus is significantly larger than that of E. brandti. The above structural differences make E. scrobiculatus more conducive to oviposition in the soil and E. brandti more conducive to oviposition in the trunk of A. altissima. (4) Overall, this study not only plays an important role in exploring the excavating mechanism during the oviposition of the two weevils, but also provides new insights into the coexistence of two weevil species on the same host A. altissima. Full article

(This article belongs to the Special Issue Bark and Wood Boring Insects - Past, Present and the Future Knowledge We Need)

► Show Figures

Figure 1

10 pages, 2365 KiB

Open AccessArticle

Regulation of Aquaporin Prip Expression and Its Physiological Function in Rhyzopertha dominica (Coleoptera: Bostrichidae)

by Lan-Pin Tan and Mei-Er Chen

Insects 2023, 14(1), 70; https://doi.org/10.3390/insects14010070 - 11 Jan 2023

Cited by 3 | Viewed by 2114

Abstract

Rhyzopertha dominica Prip (RdPrip) cDNA was cloned (GenBank accession no. OK318454), and the encoded 276-amino-acid protein indicated the typical aquaporin structure, including six transmembrane regions and two NPA motifs. The developmental and tissue profiles of RdPrip transcription were determined. RdPrip was [...] Read more.

Rhyzopertha dominica Prip (RdPrip) cDNA was cloned (GenBank accession no. OK318454), and the encoded 276-amino-acid protein indicated the typical aquaporin structure, including six transmembrane regions and two NPA motifs. The developmental and tissue profiles of RdPrip transcription were determined. RdPrip was highly transcribed in female adults, followed by larvae, pupae, and male adults. The transcriptional expression levels of RdPrip were significantly high in the ovary and hindgut (including cryptonephridial systems) compared with the foregut, testis, midgut, and Malpighian tubules. Knockdown of RdPrip in female adults did not decrease fecundity, but significantly decreased the hatching rate of eggs laid by the females. The results suggest that RdPrip functions in embryonic development, not in egg formation. In addition, the transcriptional expression level of RdPrip was lower in the spinosad-resistant strain than in the susceptible one, and the resistant strain produced fewer progeny than the susceptible strain did. These studies support the functional role of RdPrip in female reproduction. The absence of significant mortality reduction in the R. dominica exposed to spinosad after RdPrip RNAi suggests that other aquaporins that were not knocked down may exist for the excretion of metabolized pesticides. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

10 pages, 1330 KiB

Open AccessFeature PaperArticle

Detection of Arthropod-Borne Bacteria and Assessment of MALDI-TOF MS for the Identification of Field-Collected Immature Bed Bugs from Mauritania

by Jacques Sevestre, Mohamed Aly Ould Lemrabott, Jean-Michel Bérenger, Adama Zan Diarra, Ali Ould Mohamed Salem Boukhary and Philippe Parola

Insects 2023, 14(1), 69; https://doi.org/10.3390/insects14010069 - 11 Jan 2023

Cited by 6 | Viewed by 2490

Abstract

Human infestations by bed bugs have upsurged globally in recent decades, including in African countries, where recent reports pointed out an increase in infestation. Sympatric dwelling has been described for two species of bed bug parasitizing humans: Cimex hemipterus (the tropical bed bug) [...] Read more.

Human infestations by bed bugs have upsurged globally in recent decades, including in African countries, where recent reports pointed out an increase in infestation. Sympatric dwelling has been described for two species of bed bug parasitizing humans: Cimex hemipterus (the tropical bed bug) and C. lectularius. Identification of these two species is based on morphological characteristics, and gene sequencing, and may also rely on Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS). The present work aimed to assess whether MALDI-TOF MS was applicable for species level identification of immature stages of Cimex. Arthropods were collected in domestic settings in Nouakchott, Mauritania. Identification used morphological keys and MALDI-TOF MS identification was assessed for immature stages. Quantitative PCR and sequencing assays were used to detect arthropod-associated bacteria in each specimen. A total of 92 arthropods were collected, all morphologically identified as C. hemipterus (32 males, 14 females and 45 immature stages). A total of 35/45 specimens produced good quality MALDI-TOF MS spectra. Analysis allowed species level identification of all immature C. hemipterus after their spectra were entered into our in-house MALDI-TOF MS arthropod spectra database. Molecular screening allowed detection of Wolbachia DNA in each specimen. These results suggested that MALDI-TOF MS is a reliable tool for species level identification of Cimex specimens, including immature specimens. Future studies should assess this approach on larger panels of immature specimens for different Cimex species and focus on the precise staging of their different immature developmental stages. Full article

► Show Figures

Figure 1

19 pages, 6413 KiB

Open AccessArticle

Multi-Omics Reveals the Effect of Population Density on the Phenotype, Transcriptome and Metabolome of Mythimna separata

by Sibo Wang, Hongjia Yang, Yushuo Hu, Chunyu Zhang and Dong Fan

Insects 2023, 14(1), 68; https://doi.org/10.3390/insects14010068 - 10 Jan 2023

Cited by 3 | Viewed by 2115

Abstract

Population-density-dependent polymorphism is important in the biology of some agricultural pests. The oriental armyworm (Mythimna separata) is a lepidopteran pest (family Noctuidae). As the population density increases, its body color becomes darker, and the insect eats more and causes greater damage [...] Read more.

Population-density-dependent polymorphism is important in the biology of some agricultural pests. The oriental armyworm (Mythimna separata) is a lepidopteran pest (family Noctuidae). As the population density increases, its body color becomes darker, and the insect eats more and causes greater damage to crops. The molecular mechanisms underlying this phase change are not fully clear. Here, we used transcriptomic and metabolomic methods to study the effect of population density on the differentiation of second-day sixth instar M. separata larvae. The transcriptomic analysis identified 1148 differentially expressed genes (DEGs) in gregarious-type (i.e., high-population-density) armyworms compared with solitary-type (low-population-density) armyworms; 481 and 667 genes were up- and downregulated, respectively. The metabolomic analysis identified 137 differentially accumulated metabolites (DAMs), including 59 upregulated and 78 downregulated. The analysis of DEGs and DAMs showed that activation of the insulin-like signaling pathway promotes the melanization of gregarious armyworms and accelerates the decomposition of saccharides, which promotes the gregarious type to take in more food. The gregarious type is more capable of digesting and absorbing proteins and decreases energy consumption by inhibiting transcription and translation processes. The phase change traits of the armyworm are thus attributable to plasticity of its energy metabolism. These data broaden our understanding of the molecular mechanisms of insect-density-dependent polymorphism. Full article

(This article belongs to the Special Issue Insect Genome and Transcriptome Data)

► Show Figures

Graphical abstract

15 pages, 1882 KiB

Open AccessArticle

Environmental Factors Drive Chalcid Body Size Increases with Altitudinal Gradients for Two Hyper-Diverse Taxa

by Ning Kang, Hongying Hu, Zengqian Huang, Shungang Luo and Shuhan Guo

Insects 2023, 14(1), 67; https://doi.org/10.3390/insects14010067 - 10 Jan 2023

Cited by 4 | Viewed by 2155

Abstract

Body size is the most essential feature that significantly correlates with insects’ longevity, fecundity, metabolic rate, and sex ratio. Numerous biogeographical rules have been proposed to illustrate the correlation between the body sizes of different taxa and corresponding geographical or environmental factors. Whether [...] Read more.

Body size is the most essential feature that significantly correlates with insects’ longevity, fecundity, metabolic rate, and sex ratio. Numerous biogeographical rules have been proposed to illustrate the correlation between the body sizes of different taxa and corresponding geographical or environmental factors. Whether the minute and multifarious chalcids exhibit a similar geographical pattern is still little known. In this research, we analyzed morphological data from 2953 specimens worldwide, including the two most abundant and diverse taxa (Pteromalidae and Eulophidae), which are both composed of field-collected and BOLD system specimens. We examined forewing length as a surrogate of body size and analyzed the average size separately for males and females using two methods (species and assemblage-based method). To verify Bergmann’s rule, we included temperature, precipitation, wind speed and solar radiation as explanatory variables in a generalized linear model to analyze the causes of the size variation. We found that there was an increasing trend in the body size of Pteromalidae and Eulophidae with altitude. The optimal Akaike information criterion (AIC) models showed that larger sizes are significantly negatively correlated with temperature and positively correlated with precipitation, and the possible reasons for this variation are discussed and analyzed. Full article

► Show Figures

Figure 1

Journal Menu

Journal Browser

Insects, Volume 14, Issue 1 (January 2023) – 96 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI