Insects

19 pages, 6063 KB

Open AccessArticle

Expression Characteristics of Gustatory Receptor Genes in Galeruca daurica (Coleoptera: Chrysomelidae) and Adult Behavioral and Electrophysiological Responses to Host Metabolites

by Jing Gao, Jinwei Li, Haichao Wang, Jinghang Zhang, Xiaomin An, Yanyan Li, Jun Zhao, Baoping Pang and Ling Li

Insects 2026, 17(4), 442; https://doi.org/10.3390/insects17040442 - 21 Apr 2026

Viewed by 429

Abstract

Galeruca daurica (Joannis) (Coleoptera: Chrysomelidae) is an oligophagous pest in which both adults and larvae prefer to feed on Allium forage grasses of the Liliaceae family. In this study, we identified gustatory receptor (GR) genes based on the transcriptome data of G. daurica [...] Read more.

Galeruca daurica (Joannis) (Coleoptera: Chrysomelidae) is an oligophagous pest in which both adults and larvae prefer to feed on Allium forage grasses of the Liliaceae family. In this study, we identified gustatory receptor (GR) genes based on the transcriptome data of G. daurica; analyzed the expression profiles of these GR genes across different larval instars and various tissues of male and female adults using quantitative real-time PCR (qRT-PCR); detected the electrophysiological responses of the mouthparts of male and female G. daurica adults to flavonoids and carbohydrates using single sensillum recording (SSR); and recorded the changes in food consumption of G. daurica adults after feeding on six host plant-derived metabolites. A total of 26 GR genes were identified from the transcriptome data of adult and larval of G. daurica. Phylogenetic analysis was performed to screen candidate functional gustatory receptor genes, including four sugar receptors (GdauGR7, GdauGR10, GdauGR14 and GdauGR28), seven bitter receptors (GdauGR11, GdauGR16~17, GdauGR22, GdauGR25~26 and GdauGR30), and two CO₂ receptors (GdauGR15 and GdauGR20). Larval expression profiling of GdauGRs in G. daurica revealed that the relative expression levels of 17 genes exhibited dynamic changes during larval growth and development. GdauGRs were expressed to varying degrees in the antennae, mouthparts, brain, gut, and forelegs of adult G. daurica, with sex-specific differences. Notably, the expression levels of GdauGR4, GdauGR9 and GdauGR16 in the gut were extremely significantly higher than those in other tissues. In the SSR test, the six tested flavonoids and one carbohydrate were able to induce robust electrophysiological responses in the gustatory sensilla on the antennae and mouthparts of adult G. daurica at specific concentrations. In addition, the supplementation of several host-derived metabolites altered the food consumption of adult G. daurica. These findings lay a solid foundation for elucidating the molecular mechanisms underlying gustatory recognition and host adaptation in G. daurica. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

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37 pages, 2228 KB

Open AccessReview

Integrated Pest Management Strategies for Controlling Phthorimaea (Tuta) absoluta: Advances in Biological, Pheromone, and Cultural Control Methods

by Chen Zhang, Yu-Xin Wang, Xu-Dong Liu, Asim Iqbal, Qing Wang and Yu Wang

Insects 2026, 17(4), 441; https://doi.org/10.3390/insects17040441 - 21 Apr 2026

Viewed by 1617

Abstract

The tomato leaf miner, Phthorimaea (Tuta) absoluta, Meyrick 1917 is recognized as a highly destructive pest, causing significant economic losses to crops in both greenhouse and open field environments across four continents: Asia, Africa, Europe, and South America. High genetic [...] Read more.

The tomato leaf miner, Phthorimaea (Tuta) absoluta, Meyrick 1917 is recognized as a highly destructive pest, causing significant economic losses to crops in both greenhouse and open field environments across four continents: Asia, Africa, Europe, and South America. High genetic homogeneity among populations from various regions and countries indicates significant gene flow between P. absoluta populations, suggesting a lack of geographical barriers to dispersion. Furthermore, P. absoluta has developed resistance to insecticides due to target-site mutations or metabolic resistance, which enable the insect to withstand lethal doses of insecticides. To control this insect pest, the plant-mediated RNA interference (RNAi) is most promising host-induced gene silencing technique, utilized the plant’s machinery to express double-stranded (dsRNA), which triggers the RNAi pathway in P. absoluta. Due to thermal tolerance, the P. absoluta has increased its area of invasion by 600 km per year over 9 years. Female P. absoluta releases pheromones that are recognized by males with a sophisticated olfactory circuit on their antenna. Pheromone binding proteins (PBPs) play a crucial role in mate recognition and attraction, and their expression peaks during courtship, specifically around 6:00 a.m. Given its potential to significantly alter the insect genome, clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9) offer a revolutionary strategy to control P. absoluta. Furthermore, this pest has developed remarkable adaptations to survive on unfavorable hosts by secreting specific proteins from its salivary glands that detoxify plant defenses. Insecticide resistance is likely the cause of field control failures of P. absoluta. Biological control, sex pheromone traps, and cultural control are the most promising approaches to address insecticide resistance resulting from these failures. Therefore, the implementation of integrated control programs and appropriate resistance management strategies is necessary to keep P. absoluta infestations under economic damage thresholds. Full article

(This article belongs to the Special Issue Sustainable Pest Management in Agricultural Systems)

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11 pages, 2193 KB

Open AccessArticle

Assessing the Effects of Thymol and Oxalic Acid on Honey Bee Colony Condition Using Ratiometric Spectral Indicators in Honey and Beeswax

by Mira Stanković, Miroslav Nikčević, Sladjana Z. Spasić and Ksenija Radotić

Insects 2026, 17(4), 440; https://doi.org/10.3390/insects17040440 - 21 Apr 2026

Viewed by 591

Abstract

Over the past 20 years, honey bee colony declines have been driven by multiple factors, notably diseases and parasites. The parasitic mite Varroa destructor, which weakens the bees’ immune systems, has been particularly harmful. While various synthetic acaricides are used, the chemicals [...] Read more.

Over the past 20 years, honey bee colony declines have been driven by multiple factors, notably diseases and parasites. The parasitic mite Varroa destructor, which weakens the bees’ immune systems, has been particularly harmful. While various synthetic acaricides are used, the chemicals may accumulate in the beeswax, endangering colony health and allowing Varroa populations to develop resistance to these acaricides. These problems have prompted interest in organic alternatives like thymol and oxalic acid. In this study, colony health was assessed through the proteins-to-phenolics spectral ratio in honey and beeswax, determined by fluorescence spectroscopy, as a ratiometric indicator of infection level in treated hives. Over two months, hives were treated with either oxalic acid, thymol, or remained untreated as controls. Neither treatment significantly affected the proteins-to-phenolics ratios in honey, ranging from 0.30 to 0.83, or in beeswax, ranging from 1.40 to 1.83, suggesting that the incorporation of these vital constituents remains stable despite acaricide application. While thymol demonstrates potential adverse effects on bee health, careful management of treatment concentrations is essential to ensure both the efficacy of Varroa control and the preservation of honey quality. These findings provide valuable insights for beekeepers regarding the safe application of organic acaricides. Full article

(This article belongs to the Special Issue Current Advances in Pollinator Insects)

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17 pages, 3093 KB

Open AccessArticle

RNAi-Mediated Silencing of vATPase Subunit E Impairs Larval Development in Plutella xylostella, and Virtual Screening Identifies a Potential Inhibitor

by Xuetao Yu, Jinhua Luo, Jiayi Xue, Lin Lu, Pan Deng, Li Zhu, Kang Yang, Xia Wan, Yuhua Wu, Akmal Boboev, Gang Wu, Xiaohong Yan and Chenhui Shen

Insects 2026, 17(4), 439; https://doi.org/10.3390/insects17040439 - 20 Apr 2026

Viewed by 734

Abstract

The diamondback moth (Plutella xylostella) is a devastating global pest of cruciferous crops. This study explores the potential of targeting the vacuolar ATPase subunit E (PxvATPaseE) for its control. We demonstrate that PxvATPaseE is essential for larval development, showing [...] Read more.

The diamondback moth (Plutella xylostella) is a devastating global pest of cruciferous crops. This study explores the potential of targeting the vacuolar ATPase subunit E (PxvATPaseE) for its control. We demonstrate that PxvATPaseE is essential for larval development, showing high expression levels in the midgut. RNA interference (RNAi)-mediated silencing of PxvATPaseE resulted in severe growth retardation and dose-dependent mortality, with higher dsRNA doses inducing more sustained effects. Furthermore, computational virtual screening of natural compound libraries identified a high-affinity binder of PxvATPaseE, such as periplocoside D. Our results demonstrate that PxvATPaseE is a promising molecular target for controlling P. xylostella, supporting a dual-strategy approach combining RNAi and targeted chemical inhibition for future pest management solutions. Full article

(This article belongs to the Special Issue Advances in Insect Pest Management: Innovative Approaches to Enhance Plant Protection)

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13 pages, 3507 KB

Open AccessReview

Insect SVWC Proteins: A Diverse Cytokine-like Family Orchestrating Multilayered Antiviral and Antibacterial Immunity

by Yangyang Chen, Gaoying Xu, Jingao Wang, Cong Zhang, Aliyu Yusuf Abubakar and Hengchuan Xia

Insects 2026, 17(4), 438; https://doi.org/10.3390/insects17040438 - 20 Apr 2026

Viewed by 728

Abstract

The single von Willebrand factor C (SVWC) domain-containing protein family represents a crucial class of immune molecules recently identified in insects and crustaceans. Initially regarded as functional analogs of vertebrate interferons (IFNs) due to their virus-induced expression and activation of the Janus kinase-signal [...] Read more.

The single von Willebrand factor C (SVWC) domain-containing protein family represents a crucial class of immune molecules recently identified in insects and crustaceans. Initially regarded as functional analogs of vertebrate interferons (IFNs) due to their virus-induced expression and activation of the Janus kinase-signal transducer and activator of the transcription (JAK-STAT) pathway, recent studies have revealed that SVWC proteins possess far more complex functions. Many SVWC members are themselves a novel class of pattern recognition receptors (PRRs) that can directly bind to viruses and bacteria. Importantly, SVWCs are not a single entity but a highly diverse family—multiple subtypes exist in Drosophila, Bombyx mori, and shrimp—a gene expansion that implies functional differentiation. This review systematically examines the multifunctionality of SVWC proteins in insects and crustaceans, with a particular focus on the functional specialization driven by subtype diversity. We delve into the complex regulatory networks governing SVWC expression, including the differential activation by nuclear factor kappa B (NF-κB) pathways (Dorsal, Rel-2, Relish) and interferon regulatory factor (IRF) pathways. We detail the unique signaling mechanism by which SVWCs activate the JAK-STAT pathway via integrins, rather than the canonical Domeless receptor. Furthermore, we extend the discussion to the emerging roles of SVWCs as PRRs in humoral immunity (activating Toll/IMD pathways to induce antimicrobial peptides) and cellular immunity (mediating hemocyte phagocytosis). Based on current evidence, We propose that diverse SVWC subtypes may recognize distinct pathogens, bind to different integrin receptors, and activate specific STAT variants via disparate upstream induction pathways, thereby establishing a systematic and hierarchical immunoregulatory network. This understanding positions the SVWC protein family as a central hub in the insect immune network and offers a novel perspective on the complexity and evolution of invertebrate immunity. Full article

(This article belongs to the Special Issue New Insights into Molecular Mechanism of Insect–Virus Interaction)

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13 pages, 1274 KB

Open AccessArticle

Contrasting Toxicity Classes Differentially Affect Gut Microbiota Composition in Honey Bees

by Yunchao Kan, Ruoke Wang, Bing Zhang, Yu Liu, Runqiang Liu, Zhongyin Zhang, Zhaonan Zhang, Camilo Ayra-Pardo and Dandan Li

Insects 2026, 17(4), 437; https://doi.org/10.3390/insects17040437 - 20 Apr 2026

Viewed by 774

Abstract

Honey bees rely on a specialized gut microbiota for nutrition, detoxification, and immune function, yet the effects of emerging insecticides on this symbiotic system remain poorly understood. We compared the acute toxicity and short-term gut microbiota responses of Apis mellifera ligustica workers exposed [...] Read more.

Honey bees rely on a specialized gut microbiota for nutrition, detoxification, and immune function, yet the effects of emerging insecticides on this symbiotic system remain poorly understood. We compared the acute toxicity and short-term gut microbiota responses of Apis mellifera ligustica workers exposed to two insecticides with contrasting toxicity classes: the highly toxic emamectin benzoate-lufenuron (EB-LFR) and the low-toxicity ecdysone agonist RH-5849. EB-LFR was associated with observed reductions in core gut symbionts (Gilliamella, Snodgrassella, Lactobacillus), a transient increase in Bifidobacterium, and the detection of opportunistic taxa such as Serratia marcescens and Enterobacter hormaechei. In contrast, RH-5849 was associated with broad reductions in beneficial bacteria without detectable pathogen emergence, suggesting a more moderate alteration of microbiota composition. Because microbiota analyses were based on single pooled samples per treatment, these results represent exploratory, qualitative insights into early microbial responses. Together with acute toxicity data, the findings suggest that insecticides with contrasting toxicity classes may differentially affect gut microbiota composition in honey bees and highlight the value of incorporating gut microbiota endpoints into pesticide risk-assessment frameworks to better anticipate sublethal effects on pollinator health. Full article

(This article belongs to the Section Social Insects and Apiculture)

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15 pages, 458 KB

Open AccessArticle

Sustainable Rearing of Tenebrio molitor Larvae Using Peatland Biomass

by Asma Akaichi, Nazanin Fazel Dehkordi, Jan Berend Lingens, Alexandra Rath, Florian Lohkamp, Amr Abd El-Wahab, Marwa F. E. Ahmed, Nils Th. Grabowski, Kashif ur Rehman, Madeleine Plötz, Christian Visscher and Cornelia Schwennen

Insects 2026, 17(4), 436; https://doi.org/10.3390/insects17040436 - 18 Apr 2026

Viewed by 690

Abstract

To promote sustainable biomass recycling and support food security, Tenebrio molitor (TM) larvae can serve as an eco-friendly source of food and feed. This study compared the survival, growth performance, and nutritional composition of TM larvae fed five diets. The control (CON) diet [...] Read more.

To promote sustainable biomass recycling and support food security, Tenebrio molitor (TM) larvae can serve as an eco-friendly source of food and feed. This study compared the survival, growth performance, and nutritional composition of TM larvae fed five diets. The control (CON) diet contained distillers’ dried grains with solubles (DDGS) and wheat bran (WB), while the experimental diets included 10–40% lignocellulose-rich organic products from rewetted peatlands (LPRP) replacing WB, with DDGS adjusted to maintain equivalent protein levels (about 21%). A total of 2500 larvae were divided into five replicates per treatment (100 larvae each). Survival exceeded 90% across all groups. Larvae fed the CON diet had a higher final body weight than those on the 30% and 40% LPRP diets (p < 0.05), with no significant differences among the CON and 10% and 20% LPRP groups. The feed conversion ratio (fresh matter) was significantly lower in the CON and 10% LPRP groups than in the other groups (p < 0.05). Larvae fed the 10% LPRP diet showed slightly higher crude protein content (55.8%) compared to the control group (54.8%) and the other treatment groups, whereas those fed the 30% LPRP diet had the highest numerical total amino acid content. Taken together, these results indicate that incorporating 10% LPRP with DDGS and WB provides the best overall balance between growth performance and nutritional quality for TM larvae, supporting sustainable production and circular economy goals. Full article

(This article belongs to the Special Issue Insects as Food: Advances in Edible Insect Research and Applications)

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20 pages, 3018 KB

Open AccessArticle

Differences in Pigment Content and Expression of Cocoon Color Formation-Related Genes in Multiple Silkworm Strains

by Lin Zhu, Mengli Li, Zijian Huang, Yuyang Wu, Guodong Zhao and Heying Qian

Insects 2026, 17(4), 435; https://doi.org/10.3390/insects17040435 - 17 Apr 2026

Viewed by 501

Abstract

Deciphering the coloration mechanism of natural-colored cocoons in the domestic silkworm (Bombyx mori) is of great importance for the green and sustainable development of the sericulture industry. In this study, 14 silkworm strains were selected for studying differences in the coloration [...] Read more.

Deciphering the coloration mechanism of natural-colored cocoons in the domestic silkworm (Bombyx mori) is of great importance for the green and sustainable development of the sericulture industry. In this study, 14 silkworm strains were selected for studying differences in the coloration mechanism of diverse cocoon colors, and the present research carried out integrated investigations from three aspects: pigment content, differences in gene expression levels, and gene structural variation. The results demonstrated that pigment accumulation presented distinct tissue-specific and strain-specific characteristics. The middle silk gland (MSG) acts as the primary locus for pigment deposition: silkworm strains forming yellow or red cocoons accumulate carotenoids at high levels in this tissue, whereas those producing green cocoons show abundant flavonoid enrichment here. Analysis of gene expression profiles indicated that the expression patterns of core transporter genes are highly correlated with the spatial distribution of pigments. The expression level of CBP gene in the MSG is over 10-fold higher than that in the midgut (MG) among yellow/red cocoon strains. The pivotal glycosylation gene UGT86 displayed remarkably elevated expression in the MSG relative to other tissues across all green cocoon silkworm strains. The CBP gene acts as a core regulatory factor governing the transport of carotenoid pigments, and notable disparities existed in the coding region of the gene among silkworm strains with different cocoon colors. In contrast to yellow and red cocoon strains, the transcription start site of CBP gene is displaced in silkworm varieties that form green or white cocoons. In summary, this study clarified the expression patterns and variations in key pigment deposition-related genes at the population level for the first time and provided data references for the study of the biological basis and coloration mechanism of diverse cocoon colors. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

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26 pages, 1668 KB

Open AccessArticle

Edible Insects as Human Food: Perceptions of Individuals from Six Countries

by Raquel P. F. Guiné, Sofia G. Florença, Anayansi Escalante-Aburto, Rosa María Mariscal-Moreno, César Ozuna, Lucio Rodríguez-Sifuentes, Cristina Chuck-Hernández, Marijana Matek Sarić, Nada M. Boustani, Elena Bartkiene, Cristina Filip, Simona Pârvu and Monica Tarcea

Insects 2026, 17(4), 434; https://doi.org/10.3390/insects17040434 - 17 Apr 2026

Viewed by 706

Abstract

Edible insects (EIs) have been suggested as a sustainable alternative to meat from traditional sources. However, despite EIs being consumed by humans since time immemorial, it is also true that, in many areas, especially in Western countries, there is some resistance and even [...] Read more.

Edible insects (EIs) have been suggested as a sustainable alternative to meat from traditional sources. However, despite EIs being consumed by humans since time immemorial, it is also true that, in many areas, especially in Western countries, there is some resistance and even neophobia to their acceptance as food. This work aimed to investigate the perceptions about EIs and validate a corresponding scale. This descriptive cross-sectional study was carried out by means of a questionnaire survey on a sample of 3711 participants in six countries (Croatia, Lebanon, Lithuania, Mexico, Portugal and Romania). Data were analysed by factor and cluster analyses, as well as other statistical tools. The results showed that, out of the initial 36 items in the questionnaire, 24 were validated in the scale of perceptions, distributed across six factors. Cluster analysis showed that the participants could be grouped according to three clusters (Traditionalists, Shoppers and Innovators). Statistical tests revealed significant differences (p < 0.05) between the clusters in practically all sociodemographic and consumption variables studied. Finally, a word analysis of the 2263 words indicated by the participants when thinking about EIs revealed that the most frequent words were ‘disgusting’, ‘protein’, and ‘nutritive’ in all three clusters. However, differences were observed after the fourth position in the list of most frequent words. In conclusion, these results indicate that perceptions of EIs were highly variable across countries of origin and other sociodemographic groups, and that, globally, participants exhibited some neophobia towards EIs. However, they recognised their value in terms of nutrition, particularly protein. This work evidences some relevant aspects that can be useful to adapt and define targeted policies to demystify the negative perceptions about EIs and improve consumer acceptance, thus contributing to more sustainable food systems. Full article

(This article belongs to the Section Role of Insects in Human Society)

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25 pages, 12709 KB

Open AccessArticle

Faunistic Contributions to the Superfamilies Oestroidea and Muscoidea (Insecta: Diptera) of Greece and Cyprus: New Records from Five Calyptrate Families

by Gabriella Dimitra Rakopoulou, Savvas Zafeiriou, Nikoleta-Nefeli Kofou, Theodora Petanidou and Georgios Agapakis

Insects 2026, 17(4), 433; https://doi.org/10.3390/insects17040433 - 17 Apr 2026

Viewed by 595

Abstract

Knowledge of the Oestroidea and Muscoidea fauna of Greece and Cyprus remains fragmentary, with substantial parts of the two countries having never been systematically surveyed. The present study verifies the presence of Scathophaga stercoraria (Linnaeus, 1758) in Cyprus and records 16 new species [...] Read more.

Knowledge of the Oestroidea and Muscoidea fauna of Greece and Cyprus remains fragmentary, with substantial parts of the two countries having never been systematically surveyed. The present study verifies the presence of Scathophaga stercoraria (Linnaeus, 1758) in Cyprus and records 16 new species from Greece, belonging to five calyptrate families: [Anthomyia illocata Walker, 1856 (Muscoidea: Anthomyiidae); Scathophaga lutaria (Fabricius, 1794) (Muscoidea: Anthomyiidae); Fannia pallitibia (Rondani, 1866); Fannia pusio (Wiedemann, 1830) (Muscoidea: Fanniidae); and Coenosia sp. nov. 1, Coenosia sp. nov. 2, Lispe flavicincta Loew, 1847, Lispe nuba Wiedemann, 1830, Lispe orientalis Wiedemann, 1824, Lispe cf. sericipalpis (Stein, 1904), Potamia littoralis Robineau–Desvoidy, 1830 (Muscoidea: Muscidae); Apodacra radchenkoi Verves and Khrokalo, 2015, Craticulina tabaniformis (Fabricius, 1805), Miltogramma rutilans Meigen, 1824, Nyctia lugubris (Macquart, 1843) (Oestroidea: Sarcophagidae), and Linnaemya lithosiophaga (Rondani, 1859) (Oestroidea: Tachinidae)]. These records are based on the examination of 152 dry-pinned specimens from 58 localities, collected between 1978 and 2026 across Greece and Cyprus using a combination of passive (animal-baited traps, UV-bright pan traps) and active (hand collecting, net sweeping) sampling methods, together with insect material from the entomological collections of the National Museum of Natural History Goulandris and the Melissotheque of the Aegean. In addition, the first checklists of the family Fanniidae and the subfamily Scathophaginae for Greece and Cyprus are presented. Collectively, the findings presented expand the documented diversity of Greek and Cypriot Calyptratae and refine the current understanding of their biogeographic patterns, providing an updated framework for taxonomic, ecological, forensic, and other applied entomological research within the two countries. Full article

(This article belongs to the Special Issue Forensic Entomology: From Basic Research to Practical Applications)

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17 pages, 3740 KB

Open AccessArticle

Transcriptomic Evidence Reveals the IIS–FOXO–SOD2 Axis as a Core Anti-Aging Pathway in Long-Lived Queens of Odontotermes formosanus

by Yiyang Chen, Dandan Qiao, Hao Chen, Dayu Zhang and Yongjian Xie

Insects 2026, 17(4), 432; https://doi.org/10.3390/insects17040432 - 17 Apr 2026

Viewed by 757

Abstract

The reproductive caste of higher termites exhibits remarkable longevity, but the mechanisms by which they manage age-related oxidative stress during lifespan extension remain insufficiently understood. This study investigated the dynamic regulation of the insulin/IGF (IIS)–FOXO axis, a key anti-aging regulatory pathway that integrates [...] Read more.

The reproductive caste of higher termites exhibits remarkable longevity, but the mechanisms by which they manage age-related oxidative stress during lifespan extension remain insufficiently understood. This study investigated the dynamic regulation of the insulin/IGF (IIS)–FOXO axis, a key anti-aging regulatory pathway that integrates insulin signaling with downstream processes, including antioxidant defense and DNA repair, as well as the superoxide dismutase (SOD) system in female Odontotermes formosanus reproductives at various life stages (Swarming Queen (SQ), 1-Year Queen (1YQ), 8-Year Queen (8YQ)) through transcriptomic, qRT-PCR, and enzyme activity analyses. Age-dependent upregulation of IIS pathway components (InR, chico, PDK1, Akt, Sirt1, FOXO) was observed, alongside the identification of six SOD transcripts, including two SOD1, two SOD2, and two SOD3 isoforms. Notably, mitochondrial SOD2 (particularly SOD2_b) showed a progressive increase with age, exhibiting the highest enzymatic activity and being associated with reduced mitochondrial oxidative stress and the disruption of reactive oxygen species (ROS) amplification cycles. These findings suggest that O. formosanus reproductives counteract the potential lifespan-reducing effects of chronic IIS activation by maintaining or enhancing FOXO activity, thereby supporting DNA repair, antioxidant defenses, and cellular homeostasis. The IIS–FOXO–SOD2 axis is identified as a key regulator of reproductive longevity in higher termites, offering new insights into the molecular mechanisms behind lifespan extension in social insects. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

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14 pages, 3382 KB

Open AccessArticle

A True Bug with a True but Unique Chela in 100 Million-Year-Old Amber

by Carolin Haug, Fenja I. Haug, Marie K. Hörnig, Florian Braig and Joachim T. Haug

Insects 2026, 17(4), 431; https://doi.org/10.3390/insects17040431 - 17 Apr 2026

Viewed by 6934

Abstract

Grasping appendages in representatives of the group Insecta are usually of the sub-chelate (jackknifing) type. Only rarely do chelate appendages occur: Carcinothrips (Thysanoptera), Dryinidae (Hymenoptera), and Carcinocorini (Heteroptera). Here, we report a new find from about 100 million-year-old Kachin amber, representing, to our [...] Read more.

Grasping appendages in representatives of the group Insecta are usually of the sub-chelate (jackknifing) type. Only rarely do chelate appendages occur: Carcinothrips (Thysanoptera), Dryinidae (Hymenoptera), and Carcinocorini (Heteroptera). Here, we report a new find from about 100 million-year-old Kachin amber, representing, to our knowledge, the first case of a fossil of the group Insecta with a chelate type of appendage. This find is only the fourth case of an independent or convergent evolution of such a structure. A quantitative morphological comparison of over 2000 grasping structures reveals that the proximal part of the chela (in this case, the femur) has a unique shape in the fossil, unparalleled in the fossil and modern fauna. Moreover, some other new fossils reported do not possess such a shape. The mouthparts, forming a distinct beak, allow us to identify the new fossil with the distinct chela as a representative of Heteroptera. Its short beak, together with some other characteristics, indicates that it most likely is a representative of Nepomorpha. Many other details of the fossil are not well preserved, but the overall appearance shows similarities to extant and fossil representatives of Gelastocoridae, a group of terrestrial predators. Full article

(This article belongs to the Special Issue Recent Studies on Functional Morphological Diversity of Insects)

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20 pages, 40102 KB

Open AccessArticle

Three New Species, New Records, and a Key to Dryops Olivier, 1791 (Coleoptera: Dryopidae) from Brazil

by Matheus de Souza Leite Alexandre, Bruno Clarkson, André Silva Fernandes and Felipe Ferraz Figueiredo Moreira

Insects 2026, 17(4), 430; https://doi.org/10.3390/insects17040430 - 17 Apr 2026

Viewed by 881

Abstract

Dryopidae (Insecta: Coleoptera) comprise 37 genera and about 280 species, occurring on all continents except Antarctica. The Neotropical fauna of the family has been neglected for decades, despite a few recent contributions. So far, seven genera and 29 species have been recorded from [...] Read more.

Dryopidae (Insecta: Coleoptera) comprise 37 genera and about 280 species, occurring on all continents except Antarctica. The Neotropical fauna of the family has been neglected for decades, despite a few recent contributions. So far, seven genera and 29 species have been recorded from Brazil. Based on 369 adults collected in the Brazilian states of Bahia, Paraná, and Rio de Janeiro, we describe Dryops antonioi sp. nov., D. nelsimarae sp. nov., and D. simoneae sp. nov. Furthermore, we herein redescribe and provide new records for D. ovatus (Grouvelle, 1890), an updated key to the species recorded from the country and a checklist of Neotropical representatives of the genus. Full article

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

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22 pages, 2293 KB

Open AccessArticle

Application of an Electronic Nose for Early Detection of Tephritidae Infestation in Fruits

by Eirini Anastasaki, Aikaterini Psoma, Mattia Crivelli, Savina Toufexi, Maria-Vassiliki Giakoumaki and Panagiotis Milonas

Insects 2026, 17(4), 429; https://doi.org/10.3390/insects17040429 - 16 Apr 2026

Viewed by 721

Abstract

Identifying pest infestations in fresh fruits is a crucial aspect of international trade. Currently, inspections rely on visual observations and destructive sampling, which are, in most cases, quite demanding. The detection of oviposition signs or early larval development is largely not feasible. Therefore, [...] Read more.

Identifying pest infestations in fresh fruits is a crucial aspect of international trade. Currently, inspections rely on visual observations and destructive sampling, which are, in most cases, quite demanding. The detection of oviposition signs or early larval development is largely not feasible. Therefore, new methods that are sensitive and non-destructive are urgently needed to detect fruit fly infestation during inspections of fresh produce before their introduction and spread into pest-free areas. Portable electronic olfactory systems, or electronic noses (e-noses), are used in various scientific fields and industries. In this study, we evaluated the potential of a portable PEN3 electronic nose to discriminate between non-infested and infested fruits for three fruit fly species: Ceratitis capitata (Wiedemann), Bactrocera dorsalis (Hendel), and Bactrocera zonata (Saunders) (Diptera: Tephritidae). E-nose datasets were generated from samples of each combination of fruit, fruit fly species, infestation status, and storage condition. These datasets were used to develop classification models. The classification accuracy of the models ranged from 50 to 99% during calibration and cross-validation conditions. However, their performance decreased substantially when applied to independent datasets, highlighting limitations in robustness. These findings indicate that although the PEN3 system shows promise as a non-destructive detection tool, its performance is strongly influenced by seasonal and experimental variability. Further work is needed to incorporate multi-season and multi-variety datasets, improve calibration, and robust validation before practical implementation in field inspection systems. Full article

(This article belongs to the Special Issue Fruit Flies (Diptera: Tephritidae): Behavior, Ecology and Integrated Management)

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17 pages, 2168 KB

Open AccessArticle

The Potential of Landscape Plants Photinia × fraseri and Pittosporum tobira as Refuge for Natural Enemies of Pest Insects in Rice–Wheat Rotation Systems

by Qianwen Yang, Qiang Li, Xiaowei Liu, Yajun Yang, Yongming Ruan, Pingyang Zhu, Zhongxian Lu, Chuanwang Cao and Yanhui Lu

Insects 2026, 17(4), 428; https://doi.org/10.3390/insects17040428 - 16 Apr 2026

Viewed by 557

Abstract

The rice–wheat rotation is a predominant cropping pattern in China, frequently challenged by pests such as aphids in wheat, and Chilo suppressalis and Cnaphalocrocis medinalis in rice. This study investigates the potential of two common landscape plants, Photinia × fraseri and Pittosporum tobira [...] Read more.

The rice–wheat rotation is a predominant cropping pattern in China, frequently challenged by pests such as aphids in wheat, and Chilo suppressalis and Cnaphalocrocis medinalis in rice. This study investigates the potential of two common landscape plants, Photinia × fraseri and Pittosporum tobira, as functional plants for conserving natural enemies across crop cycles. Arthropod communities were systematically monitored using Malaise traps during the wheat, wheat–rice transition, and rice seasons from 2023 to 2024. Results revealed that both species successfully conserved a diverse natural enemy community, though their structural differentiation was strongly driven by seasonal variation, as confirmed by Heatmap and principal component analysis (PCA) (P. × fraseri: PC1 = 46.3%, PC2 = 23%; P. tobira: PC1 = 40.2%, PC2 = 25%). During the wheat season, both plants synergistically supported rich functional guilds, including predatory guilds (e.g., Episyrphus balteatus, Gnathonarium dentatum, and Harmonia axyridis) and parasitic guilds (e.g., Microplitis tuberculifer and Cotesia spp.). Notably, during the critical wheat-to-rice transition, these shrubs functioned as “habitat anchors,” where P. × fraseri demonstrated superior retention capacity for functional groups like Aphidius gifuensis, mitigating post-harvest habitat fragmentation. During the rice season, distinct functional complementarity emerged: P. × fraseri appeared to function as a habitat-type plant, potentially providing stable shelter for predatory groups (e.g., spiders and lady beetles), while P. tobira appeared to act as a resource-type plant, potentially attracting a significant rebound of parasitoids (e.g., Xanthopimpla flavolineata) in August. This mid-summer rebound on P. tobira was primarily attributed to its dense evergreen foliage providing a microclimatic refuge, rather than an active flowering resource. Analysis of shared dominant taxa (H. axyridis, Cotesia spp., and E. balteatus) showed highly significant seasonal fluctuations, with peak conservation during the wheat season. This study confirms that P. × fraseri and P. tobira have cross-cycle potential as a “natural enemy bank” in rice–wheat rotation agricultural systems. Their synergistic effects—integrating stable structural shelter with seasonal nutritional subsidies—support the conservation of diverse natural enemy communities throughout the annual crop cycle and significantly enhance the sustained pest control capacity of farmland ecosystems, identifying them as exemplary functional plants for ecological engineering in rice–wheat landscapes and providing a foundation for future studies on biological control efficacy. Full article

(This article belongs to the Special Issue The Role of Beneficial Insects in Pest Control)

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10 pages, 758 KB

Open AccessHypothesis

Independent Evolution of Linear and Branched Cuticular Hydrocarbons in Ants: A Hypothesis

by Abraham Hefetz

Insects 2026, 17(4), 427; https://doi.org/10.3390/insects17040427 - 16 Apr 2026

Viewed by 534

Abstract

The epicuticle of Cataglyphis niger is endowed with hydrocarbons comprising both linear and branched alkanes. For linear alkane, it is hypothesized that the primary driving force for their evolution was acquiring means for attaining cuticular impermeability that protects the ants from desiccation, and, [...] Read more.

The epicuticle of Cataglyphis niger is endowed with hydrocarbons comprising both linear and branched alkanes. For linear alkane, it is hypothesized that the primary driving force for their evolution was acquiring means for attaining cuticular impermeability that protects the ants from desiccation, and, secondarily, was co-opted as cues and signals. For example, being more abundant in foragers, they signal colony foraging intensity and, accordingly, adjust task allocation. Branched alkanes serve mostly in communication, but their evolution is less clear. Studies of the biosynthesis of both classes of hydrocarbons revealed disparate pathways, which suggests an independent evolution. The biosynthesis of branched alkanes hints at their possible evolution. They are derived from branched fatty acids, which have evolved as protective means due to their bactericidal activity. It is hypothesized that their biosynthetic pathway was secondarily co-opted for producing branched alkanes as signals and cues. Branched alkanes blend within the linear alkane layer to evenly cover the ants’ body surface and enhance the ants’ communicative capacity by conveying larger informational content due to their numerous positional and stereoisomers. The present study presents the occurrence of substantial amounts of branched fatty acids with branching position that matches that of the branched alkanes. The disparate biosynthesis pathways and the postulated differences in their evolutionary roots lend credence to the hypothesis of their independent evolution. Full article

(This article belongs to the Section Social Insects and Apiculture)

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13 pages, 757 KB

Open AccessArticle

Early-Life Heat Stress Exposes Genotype-Dependent Male Fertility Limits in Drosophila melanogaster Under Sublethal Agrochemical Exposure

by David A. Sánchez-Rodríguez, Ying Ting Yang, Felipe Martelli and Nina Wedell

Insects 2026, 17(4), 426; https://doi.org/10.3390/insects17040426 - 16 Apr 2026

Viewed by 866

Abstract

Insect populations are increasingly exposed to concurrent climate warming and agrochemical contamination, yet how these stressors interact to influence reproductive performance remains poorly understood. Because fertility can constrain population growth before survival declines, understanding how environmental stress affects reproduction is essential for predicting [...] Read more.

Insect populations are increasingly exposed to concurrent climate warming and agrochemical contamination, yet how these stressors interact to influence reproductive performance remains poorly understood. Because fertility can constrain population growth before survival declines, understanding how environmental stress affects reproduction is essential for predicting demographic responses. Here, we investigated how elevated temperatures and sublethal imidacloprid exposure during development and early-life interact with the insecticide resistance locus Cyp6g1 to influence male reproductive performance in Drosophila melanogaster. Males were reared from embryo to adulthood under factorial combinations of temperature and insecticide exposure, and mating behaviour and fertilisation success were subsequently quantified under benign assay conditions. Early-life heat reduced fertilisation success in a genotype-dependent manner, with a pronounced collapse observed in insecticide-susceptible males. Sublethal insecticide exposure modified this thermal response, restoring fertilisation success in susceptible males and producing non-additive interactions between thermal and agrochemical stress. In contrast, although mating frequency varied across treatments, it did not show the pronounced decline observed in fertilisation success, indicating that behavioural engagement does not necessarily predict functional reproductive output. These results suggest that environmental stress experienced during early-life can reshape reproductive performance, potentially through genotype-dependent shifts in physiological investment. Considering developmental stress history and genetic variation will therefore be important for predicting insect population responses to climate warming and environmental contamination. Full article

(This article belongs to the Special Issue Effects of the Environmental Temperature on Insects)

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14 pages, 2608 KB

Open AccessArticle

Biology of Bedellia somnulentella (Lepidoptera: Bedelliidae) Associated with Wild Ipomoea spp. (Convolvulaceae) as Host Plants

by Maria Jéssica dos Santos Cabral, Rodrigo Almeida Pinheiro, Isabel Moreira da Silva, José Barbosa dos Santos, Muhammad Haseeb and Marcus Alvarenga Soares

Insects 2026, 17(4), 425; https://doi.org/10.3390/insects17040425 - 16 Apr 2026

Viewed by 591

Abstract

Bedellia somnulentella (Lepidoptera: Bedelliidae) is an invasive, leaf-mining, and defoliating pest of sweet potatoes (Ipomoea batatas L.) that has recently established in Brazil. Its colonization and infestation levels in cultivated fields are influenced by the availability of wild Ipomoea species that sustain [...] Read more.

Bedellia somnulentella (Lepidoptera: Bedelliidae) is an invasive, leaf-mining, and defoliating pest of sweet potatoes (Ipomoea batatas L.) that has recently established in Brazil. Its colonization and infestation levels in cultivated fields are influenced by the availability of wild Ipomoea species that sustain populations during off-season periods. The objective was to evaluate the biology and life history of B. somnulentella feeding on wild plants of the genus Ipomoea and on I. batatas cv. Beauregard. Vegetative and reproductive parts of Ipomoea plants were collected and cultivated, and the biology and life history of B. somnulentella were studied using twenty adult pairs of the insect per host plant in a climate-controlled room. The wild species Ipomoea hederifolia L., Ipomoea indica (Burm.f.) Merr., Ipomoea purpurea L., and cultivated I. batatas were used for the assays. The experiment followed a completely randomized design with ten replicates. Hatching, larval stages, prepupa, pupa, and adult phases were observed and recorded daily. Variations in the coloration of B. somnulentella larvae feeding on leaves of I. hederifolia, I. indica, and I. purpurea were observed. The survival and development of B. somnulentella were higher on I. batatas and I. hederifolia than on I. indica and I. purpurea, mainly during the larval and adult stages. The results provide information on infestation in alternative wild hosts and on biological aspects of B. somnulentella. Full article

(This article belongs to the Special Issue Invasive Pests: Bionomics, Damage, and Management)

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28 pages, 1716 KB

Open AccessReview

Towards Bioethical and Functional Standards in the Slaughter Methods of Edible Insects: A Narrative Review

by Oscar Abel Sánchez-Velázquez and Alan Javier Hernández-Álvarez

Insects 2026, 17(4), 424; https://doi.org/10.3390/insects17040424 - 16 Apr 2026

Viewed by 793

Abstract

The rapid expansion of edible insect production has focused primarily on rearing, processing efficiency, safety, and nutritional composition, while the slaughter of insects has received comparatively little scientific and ethical scrutiny. This narrative review examines insect slaughter as a critical control point linking [...] Read more.

The rapid expansion of edible insect production has focused primarily on rearing, processing efficiency, safety, and nutritional composition, while the slaughter of insects has received comparatively little scientific and ethical scrutiny. This narrative review examines insect slaughter as a critical control point linking bioethics, physiology, and ingredient quality. The review synthesizes evidence from neurobiology, food science, and processing studies to evaluate how commonly used slaughter methods interact with biological aspects of insects. Existing literature shows that slaughter techniques influence protein stability and hydrolysis, lipid oxidation, antioxidant retention, techno-functional properties such as emulsification and gelation, as well as sensory attributes and consumer acceptance. Available evidence suggests that methods designed to rapidly suppress metabolic activity may be associated with improved preservation of certain nutritional and functional parameters, although findings remain species- and context-dependent. The review further highlights major knowledge gaps, including the lack of species- and life-stage-specific welfare indicators and standardized assessment protocols. Overall, the findings support the need to reconceptualize insect slaughter as a strategic upstream decision rather than a neutral processing step. Integrating ethical considerations with nutritional, functional, and regulatory perspectives is essential for establishing science-based standards and ensuring the responsible development of edible insect-based food and feed systems. Full article

(This article belongs to the Special Issue Impact of Killing and Processing Conditions on Edible Insect Quality for Food Applications)

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17 pages, 3404 KB

Open AccessArticle

Robust Fine-Grained Pest Classification via Boundary-Aware Attention and Growth-Stage Supervision

by Xinliang Liu, Ruiming Zhu and Yuying Cao

Insects 2026, 17(4), 423; https://doi.org/10.3390/insects17040423 - 15 Apr 2026

Viewed by 509

Abstract

Accurate pest identification plays a critical role in effective pest management and sustainable agricultural production. However, fine-grained pest classification is inherently challenging due to low inter-class separability, significant intra-class variability, and complex environmental interference. To address these challenges, we develop a boundary-aware channel-spatial [...] Read more.

Accurate pest identification plays a critical role in effective pest management and sustainable agricultural production. However, fine-grained pest classification is inherently challenging due to low inter-class separability, significant intra-class variability, and complex environmental interference. To address these challenges, we develop a boundary-aware channel-spatial attention network to strengthen discriminative feature learning while suppressing background noise. The proposed attention module enhances fine-grained structural and boundary cues to improve inter-class separability under cluttered field conditions. Furthermore, auxiliary label supervision based on pest growth stages is incorporated to model developmental variations and enhance intra-class consistency. Experiments on the IP102 dataset demonstrate that the proposed method consistently outperforms state-of-the-art baselines in classification accuracy, validating its effectiveness for fine-grained agricultural pest classification. These results highlight the potential of integrating boundary-aware attention mechanisms with growth-stage supervision for robust real-world pest classification. Full article

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

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22 pages, 2445 KB

Open AccessArticle

Diptera in the Forensic Investigation of Human Deaths in Great Britain and the Dominant Role of Calliphora vicina (Calliphoridae) in Estimating a Minimum Post-Mortem Interval

by Martin J. R. Hall

Insects 2026, 17(4), 422; https://doi.org/10.3390/insects17040422 - 15 Apr 2026

Cited by 1 | Viewed by 860

Abstract

Saprophagic flies can have a vital role in forensic investigations of suspicious death by providing an estimate of the minimum post-mortem interval (minPMI). An exemplar blow fly species, Calliphora vicina (Diptera: Calliphoridae), is frequently reported as being of greatest importance in this role, [...] Read more.

Saprophagic flies can have a vital role in forensic investigations of suspicious death by providing an estimate of the minimum post-mortem interval (minPMI). An exemplar blow fly species, Calliphora vicina (Diptera: Calliphoridae), is frequently reported as being of greatest importance in this role, but without significant corroborating evidence. Therefore, the present study examined 122 anonymised, historic cases of suspicious death investigated in Great Britain (GB) to determine the role of Diptera and of C. vicina in particular. Thirty-seven fly species in eighteen families were recorded, with greater diversity outdoors (17 families) than indoors (11 families). Family diversity and the age of the oldest developmental stage increased as estimated minPMI increased. Indoor minPMIs tended to be lower than outdoor minPMIs, probably due to the higher likelihood of finding a body indoors. The most commonly collected family and species were Calliphoridae and C. vicina, respectively, the latter recorded in 69.7% (85/122) of all cases. The four main reasons for the importance of C. vicina are: (1) widespread distribution; (2) broad seasonality; (3) low thermal tolerance; and (4) ability to colonise bodies soon after death. It was used to determine minPMI in 85.9% of cases in which it was collected (73/85). Where a most likely PMI could be compared by regression analysis with a minPMI from C. vicina evidence, the relationship was robust (R² > 0.98), accurate to within 2.5–2.7 days at a most likely PMI of 20 days. With greater research effort, Calliphora vicina and more neglected fly species can have an increasing role in future forensic investigations of suspicious death. Full article

(This article belongs to the Special Issue Forensic Entomology: From Basic Research to Practical Applications)

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6 pages, 181 KB

Open AccessArticle

Comparative Efficacy of Different Attractants for Surveillance of Synanthropic Flies Across Seven Zoogeographical Regions of China

by Chao Wang, Taotian Tu, Xiaojuan Ma, Xiaojing Shen, Hong Tao, Yujuan Fan, Kaiwang Li, Xiaomei Zhou, Shoujiang Li, Wuhan Liu and Qiyong Liu

Insects 2026, 17(4), 421; https://doi.org/10.3390/insects17040421 - 15 Apr 2026

Viewed by 526

Abstract

Accurate identification of fly species composition and their responses to attractants is critical for risk assessment and targeted vector control. To evaluate the efficacy of different attractants in surveillance and their species-specific trapping biases, a standardized field study was conducted from June to [...] Read more.

Accurate identification of fly species composition and their responses to attractants is critical for risk assessment and targeted vector control. To evaluate the efficacy of different attractants in surveillance and their species-specific trapping biases, a standardized field study was conducted from June to September 2021 across seven representative cities in China’s major zoogeographical regions: Xining, Ürümqi, Yanji, Beijing, Chongqing, Kunming, and Sanya. Cage traps baited with either fish offal or sugar–vinegar solution were deployed, supplemented by hand-net collection. A total of 134 traps were set, yielding 2132 flies belonging to 21 species. Fish offal captured 1961 flies (91.9%), significantly more than the 101 flies (4.7%) caught with sugar–vinegar solution (χ² = 1582.3, p < 0.001). Lucilia sericata was the dominant species (885 individuals, 41.51%), followed by L. cuprina (178, 8.35%), Sarcophaga portschinskyi (127, 5.96%), and Sarcophaga africa (100, 4.70%). High-risk taxa (Calliphoridae and Sarcophagidae) were almost exclusively attracted to fish offal. Our findings demonstrate that protein-based baits, such as fish offal, are substantially more effective than traditional sugar–vinegar solutions for capturing epidemiologically relevant fly species across diverse ecological zones in China. We recommend prioritizing proteinaceous attractants in national fly surveillance programs and advocate for routine species-level identification to enable risk-informed vector monitoring. Full article

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

23 pages, 1214 KB

Open AccessArticle

Refining the Moderate Inclusion Range of Dried Asian Watermeal (Wolffia globosa) in the Diets of Two-Spotted Crickets (Gryllus bimaculatus): Integrating Segmented Regression and Nutritional Self-Selection

by Jamlong Mitchaothai, Rachakris Lertpatarakomol, Achara Lukkananukool, Tassanee Trairatapiwan, Natnaree Kaewsiri and Nils T. Grabowski

Insects 2026, 17(4), 420; https://doi.org/10.3390/insects17040420 - 15 Apr 2026

Viewed by 542

Abstract

The integration of rapidly renewable biomass into insect production systems has been proposed as a strategy to improve resource-use efficiency in insect production. This study evaluated the graded inclusion levels of dried watermeal (Wolffia globosa) in diets of two-spotted crickets ( [...] Read more.

The integration of rapidly renewable biomass into insect production systems has been proposed as a strategy to improve resource-use efficiency in insect production. This study evaluated the graded inclusion levels of dried watermeal (Wolffia globosa) in diets of two-spotted crickets (Gryllus bimaculatus) and assessed voluntary nutrient regulation under free-choice feeding. Four fixed-inclusion diets (0%, 25%, 35%, and 45% watermeal) and one self-selection treatment were tested over 28 days. Growth performance, feed conversion ratio (FCR), survival rate (Surv), production index (PI), and whole-body composition were determined. Repeated-measures analysis using linear mixed-effects models indicated that treatment, week, and their interaction were statistically significant (p ≤ 0.024). However, partial R² analysis showed that the independent contributions of treatment and week were negligible, whereas the treatment × week interaction explained measurable variance, indicating that dietary effects were primarily expressed through time-dependent responses. Segmented regression identified a breakpoint at 35% watermeal inclusion (95% CI: 24.93–45.07), indicating that PI was the highest within a moderate supplementation range under the present fixed-diet conditions rather than at a precise single optimum. Inclusion levels beyond this threshold reduced performance. Under free-choice conditions, crickets progressively increased watermeal intake with age and maintained stable nitrogen-free extract (NFE):crude protein (CP) and gross energy (GE):CP intake ratios, selecting an average of 25–35% watermeal over the experimental period. This supplementation range improved feed efficiency and protein deposition while limiting lipid accumulation, suggesting improved energy–protein balance and nutrient partitioning. The self-selection result is interpreted as evidence of behavioral intake regulation under choice conditions and not as direct validation of the segmented-regression breakpoint. Collectively, these findings provide complementary statistical and behavioral evidence supporting a biologically relevant moderate inclusion range (approximately 30–35%) of dried watermeal. Full article

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

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24 pages, 1518 KB

Open AccessArticle

The Association Between Soil Sampling and Bait Traps in Wireworm Monitoring: A Methodological and Statistical Approach

by Lorenzo Furlan, Giancarlo Bourlot, Annalisa Turchi, Valerio Snichelotto, Maddalena Cappello Fusaro and Stefano Bona

Insects 2026, 17(4), 419; https://doi.org/10.3390/insects17040419 - 15 Apr 2026

Viewed by 512

Abstract

The key to implementing IPM of wireworms effectively is to associate feasible, reliable and affordable sampling methods with well-defined damage thresholds. As wireworms live underground, they cannot be observed directly, thus estimating population levels can be challenging. Soil sampling to ascertain larval density [...] Read more.

The key to implementing IPM of wireworms effectively is to associate feasible, reliable and affordable sampling methods with well-defined damage thresholds. As wireworms live underground, they cannot be observed directly, thus estimating population levels can be challenging. Soil sampling to ascertain larval density is very time-consuming, and although the use of bait traps is much more time-effective, it is unclear how wireworm numbers in bait traps are associated with wireworm density. The work described herein was conducted between 1993 and 1999 in two regions of Northern Italy: Veneto and Piedmont. The experimental protocol involved placing soil bait traps in a 15–30 m × 10 m grid in selected cultivated fields and taking a soil sample 3 m from the location of each bait trap. The number of monitoring points ranged from 12 to 48 per site. Both trap contents and soil cores were put in funnels to dry out, forcing the wireworms to move and fall into a vial, according to the Berlese method. A moderate association was found between the number of wireworms (Agriotes brevis, A. sordidus and A. ustulatus) caught by the bait traps and by soil sampling, indicating a potential for reciprocal estimation between methods. In other words, the number of bait-trap catches can be estimated by soil sampling (e.g., when bait traps cannot be used due to low temperatures or when growing plants cover a field) and vice versa. The potential of bait traps for catching wireworms was shown to be 5 to 25 times higher than the potential of soil sampling. The threshold values for soil samples, which were derived from the original bait-trap values, range between 15 and 20 larvae/m². Full article

(This article belongs to the Special Issue Optimizing Insect Trap Systems: Advances in Lures, Dispensers, and Field Performance)

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15 pages, 9246 KB

Open AccessArticle

Upregulation of Two Cuticular Proteins Is Associated with Resistance to Beauveria bassiana in Crowded Mythimna separata

by Wenmeng Li, Jing Liao, Lingling Li, Changgeng Dai, Yang Hu, Yuhan Qian and Hongbo Li

Insects 2026, 17(4), 418; https://doi.org/10.3390/insects17040418 - 15 Apr 2026

Viewed by 761

Abstract

Mythimna separata, an important insect pest of grain crops, exhibits density-dependent prophylaxis (DDP). Most studies have focused on DDP from the perspective of immune system regulation. In this report, we show that two cuticular protein genes, MsCP1 and MsCP2, are involved in [...] Read more.

Mythimna separata, an important insect pest of grain crops, exhibits density-dependent prophylaxis (DDP). Most studies have focused on DDP from the perspective of immune system regulation. In this report, we show that two cuticular protein genes, MsCP1 and MsCP2, are involved in DDP of M. separata. MsCP1 and MsCP2 were highly expressed in 4th and 5th instar larvae of the M. separata gregarious high-density phase as compared to solitary, low-density individuals. The expression levels of MsCP1 and MsCP2 were significantly higher in the cuticle of gregarious larvae than in solitary individuals. When MsCP1 and MsCP2 were knocked down by star polycation (SPc) nanocarrier-mediated RNA interference (RNAi), the expression levels of the two genes were significantly downregulated in gregarious larvae as compared to dsGFP/SPc-treated gregarious larvae but were not significantly different from dsGFP/SPc-treated solitary larvae. Furthermore, silencing of MsCP1 and MsCP2 caused abnormal molting, alterations in ultrastructure, and reduced cuticle thickness in gregarious larvae. The mortality rates in dsMsCP1/SPc- and dsMsCP2/SPc-treated gregarious larvae were significantly higher after infection with the entomopathogenic fungus Beauveria bassiana as compared to the dsGFP/SPc-treated gregarious larva but were not significantly different from mortality rates in dsGFP/SPc-treated solitary larvae. Taken together, these findings suggest that upregulation of MsCP1 and MsCP2 are associated with resistance of gregarious M. separata to B. bassiana. These results broaden our understanding of insect DDP and are of great significance in the biological control of M. separata. Full article

(This article belongs to the Special Issue Migration and Outbreak Mechanisms of Migratory Pests)

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23 pages, 9786 KB

Open AccessArticle

A Revision of the Prionus gahani Species Group (Coleoptera: Cerambycidae: Prioninae: Prionini)

by Mei-Ying Lin and Alain Drumont

Insects 2026, 17(4), 417; https://doi.org/10.3390/insects17040417 - 14 Apr 2026

Viewed by 654

Abstract

This study contributes to the taxonomic research on the “Prionus gahani” species group, which includes six species. A new species, Prionus zhumingyui Lin & Drumont, sp. nov., is described from Guangdong Province, China. The new species is distinguished by having pronotum [...] Read more.

This study contributes to the taxonomic research on the “Prionus gahani” species group, which includes six species. A new species, Prionus zhumingyui Lin & Drumont, sp. nov., is described from Guangdong Province, China. The new species is distinguished by having pronotum longer, antennomere III with obvious apical lobe more stretched outward and cone-shaped. Illustrations of the habitus and genitalia of the new species and other four species are provided. The habitats and collecting experiences of four species are provided: P. zhumingyui Lin & Drumont, sp. nov., P. sontinh Do, Drumont & Komiya, 2019 (with new locality information), P. antonkozlovi Drumont & Komiya, 2021, and P. gahani Lameere, 1912 (with female described for the first time). It is concluded that the species of this group are diurnal, although they have somber colors. Their small compound eyes (especially compared with other Prionus species, which have large compound eyes and are attracted to light) are well-matched to their diurnal lifestyle. Full article

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

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18 pages, 6980 KB

Open AccessArticle

Understanding the Chemosensory and Detoxification Mechanisms in the Oriental Fruit Fly, Bactrocera dorsalis

by Saleem Jaffar and Yongyue Lu

Insects 2026, 17(4), 416; https://doi.org/10.3390/insects17040416 - 14 Apr 2026

Viewed by 882

Abstract

Bactrocera dorsalis (Hendel) is a major fruit-feeding pest that poses a severe and persistent threat to the horticulture industry in tropical and subtropical regions. Methyl eugenol (ME) is a powerful male-specific attractant phytochemical and pheromone precursor that has been widely exploited in lure-and-kill [...] Read more.

Bactrocera dorsalis (Hendel) is a major fruit-feeding pest that poses a severe and persistent threat to the horticulture industry in tropical and subtropical regions. Methyl eugenol (ME) is a powerful male-specific attractant phytochemical and pheromone precursor that has been widely exploited in lure-and-kill pest management programs. Upon ingestion, ME is metabolized (E)-coniferyl alcohol (E-CF) and 2-allyl-4,5-dimethoxyphenol (DMP), which are stored in the male rectal glands and released during courtship to attract females. Despite its ecological significance, the fundamental molecular mechanism underlying ME perception remains poorly understood. Here, we performed a comparative transcriptomic analysis of ME-responsive and ME-non-responsive male B. dorsalis across four tissues (head, gut, midleg, and wing). A total of 15,727 genes were annotated, of which 970 were associated with odorant-binding proteins (OBPs), odorant receptors (ORs), gustatory receptors (GRs), ionotropic receptors (IRs), and chemosensory proteins (CSPs), as well as detoxification families comprising cytochrome P450s (CYPs), carboxylesterases (CaEs), glutathione S-transferases (GSTs), and uridine diphosphate (UDP)-glycosyltransferases (UGTs), and the stress-related heat shock proteins (HSPs) genes. Differential expression analysis identified 7222, 7763, and 6105 differentially expressed genes (DEGs) in the head, gut, and wings/midlegs, respectively, between ME-responsive and ME-non-responsive males. Notably, CYPs, UGTs, and HSPs involved in detoxification and stress response were significantly downregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that CYPs were significantly enriched in metabolic detoxification pathways. These findings reveal a complex molecular interplay between olfaction and detoxification and suggest that ME induces coordinated genetic pathways supporting survival, reproduction, and environmental adaptability. This knowledge provides a foundation for the development of eco-friendly pest management strategies targeting these molecular mechanisms. Full article

(This article belongs to the Special Issue Insect Transcriptomics)

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19 pages, 3011 KB

Open AccessArticle

Contributions of ABC Transporters and Cytochrome P450s to the Tolerance in Antheraea pernyi Against Beta-Cypermethrin

by Tianyi Zhang, Xin Chen, Junshan Chen, Peifeng Liu, Fengquan Liu, Miaomiao Chen, Liang Xu, Shiwen Zhao and Xisheng Li

Insects 2026, 17(4), 415; https://doi.org/10.3390/insects17040415 - 13 Apr 2026

Viewed by 617

Abstract

Antheraea pernyi larvae growing in the wild suffer damage from the drift diffusion of insecticides used in surrounding farmland. In this study, we assessed the toxicity of beta-cypermethrin, chlorantraniliprole, imidacloprid, and thiamethoxam to different A. pernyi strains. It was found that the lowest [...] Read more.

Antheraea pernyi larvae growing in the wild suffer damage from the drift diffusion of insecticides used in surrounding farmland. In this study, we assessed the toxicity of beta-cypermethrin, chlorantraniliprole, imidacloprid, and thiamethoxam to different A. pernyi strains. It was found that the lowest LC₅₀ value of the Liaocanda9 strain against beta-cypermethrin (0.008 mg/L) was significantly higher than that of the Kangda strain (0.0047 mg/L). Additionally, beta-cypermethrin exposure was associated with significant increases in detoxification and antioxidant enzyme activities in both strains. Transcriptomic analysis showed that differentially expressed genes (DEGs) were significantly enriched in pathways related to oxidoreductase activity and transmembrane transporter activity terms. Furthermore, these genes were differentially expressed following the beta-cypermethrin exposure. The dsRNA injection treatment effectively inhibited the expression of P450 genes, thereby reducing the tolerance of A. pernyi against beta-cypermethrin by 25.93–55.56%. Molecular docking predicted that beta-cypermethrin bound to ABCG1, ABCG5, and CYP9A22 with hydrogen bonds. These results indicate that ABC transporters and P450s contribute to the tolerance of A. pernyi against beta-cypermethrin. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

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21 pages, 2288 KB

Open AccessArticle

Filling the Gap: Establishing a Statewide Tick and Tick-Borne Pathogen Surveillance Program

by Kyndall C. Dye-Braumuller, Lídia Gual-Gonzalez, Emily Owens Pickle, Christopher Lee, Madeleine M. Meyer-Torelli, Chris L Evans, Jennifer G. Chandler, Rebecca T. Trout Fryxell and Melissa S. Nolan

Insects 2026, 17(4), 414; https://doi.org/10.3390/insects17040414 - 12 Apr 2026

Viewed by 956

Abstract

Individuals in the southeastern United States of America (USA) have an increasing risk of contracting a tick-borne disease. Land use changes, changing climate, and redistribution of both ticks and their hosts make systematic tick and tick-borne pathogen investigation crucial for public health protection. [...] Read more.

Individuals in the southeastern United States of America (USA) have an increasing risk of contracting a tick-borne disease. Land use changes, changing climate, and redistribution of both ticks and their hosts make systematic tick and tick-borne pathogen investigation crucial for public health protection. Prior to 2020, South Carolina had limited data on tick species distribution and tick infection rates. In this work, we describe establishment of a sustainable tick and tick-borne pathogen collaborative network for South Carolina. A major determinant of program success was sharing work effort between the University of South Carolina, the South Carolina Department of Public Health, and key partners including state park employees, local veterinarians, students, and volunteers. The program collected questing ticks from public lands and host-attached ticks from animal shelters. Amblyomma americanum was the most commonly collected tick, with highest density in South Carolina’s southern coastal region. A greater tick species diversity was seen in animal shelter collected versus questing ticks. Pathogen testing results yielded a high presence of Rickettsia amblyommatis among Am. americanum ticks with several other Rickettsia spp. detected including Rickettsia parkeri, Candidatus R. andeanae, R. montanensis, and R. asembonensis. Additional Rickettsiales detected included multiple Ehrlichia and Anaplasma species, with higher presence in the state’s northern region. Borrelia burgdorferi sensu stricto was detected in one questing Ixodes keiransi from the southern coastal region. The current report presents the initial steps for pathogen and tick species surveillance in South Carolina, providing successes and pitfalls as a model for other states and regions to establish similar efforts to improve national tick surveillance. Full article

(This article belongs to the Section Medical and Livestock Entomology)

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Epidemiology, Associated Factors and Implications for Effective Control of Pediculosis Among Primary Schoolgirls in Thailand: A Cross-Sectional Study

by Manachai Yingklang, Patchana Hengboriboonpong Jaidee, Penchom Janwan, Wanchai Maleewong, Na T. D. Tran and Tongjit Thanchomnang

Insects 2026, 17(4), 413; https://doi.org/10.3390/insects17040413 - 10 Apr 2026

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Abstract

Pediculosis remains a public health problem among primary schoolchildren worldwide, including in Thailand. This study aimed to determine the prevalence of pediculosis and identify associated determinants among primary schoolgirls from different socio-geographic regions of Thailand to inform effective control strategies. A cross-sectional survey [...] Read more.

Pediculosis remains a public health problem among primary schoolchildren worldwide, including in Thailand. This study aimed to determine the prevalence of pediculosis and identify associated determinants among primary schoolgirls from different socio-geographic regions of Thailand to inform effective control strategies. A cross-sectional survey was conducted among 494 schoolgirls from eastern, northeastern, and southern provinces. Data on demographic characteristics, socioeconomic status, personal hygiene practices, parental knowledge and attitudes toward head lice, and school health policies were collected using questionnaires and interviews with school administrators. Univariable analyses and a generalized linear mixed model (GLMM) with school as a random effect were used to account for clustering. The overall prevalence of pediculosis was 50.81% (95% CI: 46.31–55.20), with significant variation across provinces. In univariable analysis, several factors were associated with infestation. However, after accounting for clustering, only class level (adjusted OR = 3.09; 95% CI: 1.31–7.29) and self-performed hair washing (adjusted OR = 2.93; 95% CI: 1.57–5.49) remained significantly associated with pediculosis, while other associations were attenuated. Parental knowledge was moderate, and commonly held beliefs regarding prevention and treatment varied. None of the participating schools had routine head lice screening policies. These findings indicate that pediculosis is likely influenced by both individual and school-level factors. Control efforts may benefit from coordinated school-based approaches, alongside improved access to effective treatment and targeted health education. Full article

(This article belongs to the Section Other Arthropods and General Topics)

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Insects, Volume 17, Issue 4 (April 2026) – 90 articles

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