Insects

16 pages, 7361 KB

Open AccessArticle

Integrated Transcriptomic and Metabolomic Insights into “I See You” (ISY) Defensive Behavior in Apis cerana Against Vespa velutina

by Yijie Chen, Xueling Xu, Yingjiao Li, Ning Ji, Yiwei Ruan, Mei Yang, Hongji Huang, Liulin Yang, Xiaoyu Cao and Jianghong Li

Insects 2025, 16(10), 1047; https://doi.org/10.3390/insects16101047 (registering DOI) - 13 Oct 2025

Abstract

Vespa velutina (V. velutina) is a globally widespread predator of honeybees, posing a serious threat to them. Apis cerana (A. cerana) has acquired the ability to partially thwart the predation of the wasps, but the molecular mechanism by which [...] Read more.

Vespa velutina (V. velutina) is a globally widespread predator of honeybees, posing a serious threat to them. Apis cerana (A. cerana) has acquired the ability to partially thwart the predation of the wasps, but the molecular mechanism by which it responds to V. velutina attacks is unknown. Here, both transcriptomic and metabolomic analyses were integrated to decipher what happened in the brain tissues of A. cerana exposed to V. velutina attacks. Transcriptomic analysis revealed 296 differentially expressed genes (DEGs) that were significantly enriched in neural signaling pathways (particularly serotonin and dopamine transmission), the cAMP signaling pathway, and energy metabolism. Metabolomic results showed that V. velutina attacks affected 38 metabolic pathways involving 86 differentially expressed metabolites (DEMs), primarily including amino acids, nucleotides, and carbohydrates. Several metabolites, such as isocitrate, xanthine, and adenosine, were upregulated in response to the hornet presence. Combined pathway analysis indicated an upregulation of the purine and tyrosine metabolism pathways, highlighting their critical role in A. cerana against invasive hornets. The results of this study will help to understand the molecular mechanisms of A. cerana in response to V. velutina attacks and provide valuable insights for enhancing collective defensive behavior against V. velutina in honeybees. Full article

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

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27 pages, 4953 KB

Open AccessArticle

Genome-Wide Analysis and Functional Correlation of Tomato JAZ Genes Under Tuta absoluta Infestation and Nanoparticle-Induced Defense

by Inzamam Ul Haq, Abdul Basit, Moazam Hyder, Mirza Naveed Shahzad, Asim Abbasi, Yasir Sharif, Muhammad Adeel Ghafar, Xiangyun Cai, Nazih Y. Rebouh and Youming Hou

Insects 2025, 16(10), 1046; https://doi.org/10.3390/insects16101046 - 13 Oct 2025

Abstract

Tomato (Solanum lycopersicum) production is increasingly threatened by Tuta absoluta, a destructive pest that compromises yield and quality. To explore sustainable alternatives to conventional insecticides, we investigated the jasmonate-mediated defense pathway by performing a genome-wide characterization of the JAZ gene [...] Read more.

Tomato (Solanum lycopersicum) production is increasingly threatened by Tuta absoluta, a destructive pest that compromises yield and quality. To explore sustainable alternatives to conventional insecticides, we investigated the jasmonate-mediated defense pathway by performing a genome-wide characterization of the JAZ gene family in S. lycopersicum. A total of 39 SlJAZ genes were identified and mapped to 12 chromosomes. Detailed analysis revealed conserved motifs, diverse exon–intron structures, four major phylogenetic groups, and the presence of multiple MeJA- and stress-responsive cis-elements. Synteny analysis indicated gene duplication events and evolutionary conservation with Arabidopsis and potato. Small RNA predictions suggested that 33 SlJAZ genes are targeted by 69 microRNAs, implying multilayered regulation. Transcriptome analysis under four treatment conditions—mesoporous silica nanoparticles (MSNs) ± pest infestation—revealed 21 differentially expressed SlJAZ genes. SlJAZ1, SlJAZ19, SlJAZ20, and SlJAZ22 were notably upregulated under the combined MSN and pest treatment, with expression patterns validated by qRT-PCR (R² = 0.92). Phenotypic assessment of leaf damage index, larval survival rate, and number of leaf mines showed reduced pest activity in MSN-treated plants. Regression analysis demonstrated significant negative correlations between expression levels of SlJAZ20, SlJAZ26, and SlJAZ29 and pest-related damage traits. These findings indicate that MSNs function as effective elicitors of JA-responsive defense in tomato and modulate the expression of specific JAZ genes linked to enhanced resistance. The study provides a valuable foundation for integrating nanotechnology with molecular defense strategies to promote sustainable pest management. Full article

(This article belongs to the Special Issue Research on Insect Molecular Biology)

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10 pages, 833 KB

Open AccessArticle

Behavioral Suppression and Rapid Lethality: Beauveria bassiana B4 Targets Adult Monochamus alternatus for Sustainable Management of Pine Wilt Disease

by Yaqi Zhang, Xuejie Zhang, Liudi An, Dongfeng Gong, Jinsheng Wang, Huitao Bi, Yi Zheng, Lei Cao and Shaohui Lu

Insects 2025, 16(10), 1045; https://doi.org/10.3390/insects16101045 - 12 Oct 2025

Abstract

Pine wilt disease, transmitted primarily by Monochamus alternatus (Hope, 1842) adults, causes severe ecological and economic losses globally. Conventional chemical controls face challenges of resistance and non-target toxicity. This study identified Beauveria bassiana (Bals.-Criv.) Vuill. strain B4 as a high-virulence biocontrol agent against [...] Read more.

Pine wilt disease, transmitted primarily by Monochamus alternatus (Hope, 1842) adults, causes severe ecological and economic losses globally. Conventional chemical controls face challenges of resistance and non-target toxicity. This study identified Beauveria bassiana (Bals.-Criv.) Vuill. strain B4 as a high-virulence biocontrol agent against adult M. alternatus. Laboratory bioassays compared four strains (B1–B4), with B4 exhibiting rapid lethality (LT₅₀ = 6.61 days at 1 × 10⁸ spores/mL) and low median lethal concentration (LC₅₀ = 9.63 × 10⁵ spores/mL). Critically, B4 infection induced significant behavioral suppression, including reduced appetite and mobility prior to death. In forest trials, pheromone-enhanced nonwoven fabric bags impregnated with B4 spores reduced trap catches by 66.4% within one month, with effects persisting for over a year without reapplication. The slow-release carrier system enabled continuous spore dissemination and sustained population suppression. These results demonstrate that B4’s dual action—rapid lethality and behavioral disruption—provides an effective, eco-friendly strategy for sustainable pine wilt disease management. Full article

(This article belongs to the Topic Advances in Integrated Pest Management: New Tools and Tactics for Pest Control)

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21 pages, 2715 KB

Open AccessArticle

Comparative Transcriptome Analysis of Rhynchophorus ferrugineus (Coleoptera: Curculionidae) Reveals Potential Mechanisms Involved in the Toxication and Detoxification of the External Immune Compound p-Benzoquinone Present in Oral Secretions

by Juan Chen, Yu-Chen Pu, Wen-Qing You, Ya-Nan Ji, Can-Hui Ding, Zong-Wei Zheng, Yi-Fan Wang and You-Ming Hou

Insects 2025, 16(10), 1044; https://doi.org/10.3390/insects16101044 - 11 Oct 2025

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Abstract

p-Benzoquinone (PBQ), a highly toxic compound, is the main active component in larval oral secretions of red palm weevil (RPW), Rhynchophorus ferrugineus, playing critical roles in external immunity and pathogen defense. In this study, we demonstrated that pathogens effectively induce RPW larval [...] Read more.

p-Benzoquinone (PBQ), a highly toxic compound, is the main active component in larval oral secretions of red palm weevil (RPW), Rhynchophorus ferrugineus, playing critical roles in external immunity and pathogen defense. In this study, we demonstrated that pathogens effectively induce RPW larval external immune responses. On this basis, the toxicity of PBQ to third-instar larvae was determined, with poisoning symptoms observed. The differences in gene expression between larvae before and after treatment with PBQ were analyzed by transcriptome sequencing to potentially involve the mechanisms of PBQ toxicity on larvae and the mechanisms of detoxification in the infected larvae. The results indicated that PBQ exposure was associated with altered expression of chitinase (CHI) and phenoloxidase (PO) genes in RPW larvae, which not only affects the digestion and degradation of the old cuticle but also activates phenoloxidase, further oxidizing tyrosine for its conversion into DOPA and dopamine, resulting in the generation of melanin and different degrees of cuticular melanization. The transcriptional changes further suggest that RPW larvae may employ metabolic processes to counteract the external immune-active compound PBQ toxicity by regulating the expression levels of detoxifying enzyme-encoding genes, such as cytochrome P450 (CYP450), glutathione S-transferase (GST), and ATP-binding cassette transporter (ABC). Our research provides potential novel strategies for pest control by targeting insect metabolic detoxification systems. Full article

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

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11 pages, 1342 KB

Open AccessArticle

Drylands Under Pressure: Responses of Insect Density to Land-Use Change in a Tropical Desert

by Anshuman Pati, Indranil Paul and Sutirtha Dutta

Insects 2025, 16(10), 1043; https://doi.org/10.3390/insects16101043 - 11 Oct 2025

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Abstract

Habitat alteration due to agricultural expansion and heavy livestock grazing is a major threat for open natural ecosystems (ONEs). Within the Indian Thar Desert, such land-use transformations are altering native grassland habitats, with consequential effects on insect communities that perform vital ecological functions [...] Read more.

Habitat alteration due to agricultural expansion and heavy livestock grazing is a major threat for open natural ecosystems (ONEs). Within the Indian Thar Desert, such land-use transformations are altering native grassland habitats, with consequential effects on insect communities that perform vital ecological functions and support higher trophic levels. Between 2020 and 2022, we surveyed a 641 km² area, using belt transect and visual detection methods, to quantify insect densities at the order level across different seasons. Linear mixed-effect (LME) models revealed that the orthopteran insect densities, primarily grasshoppers, were significantly higher in grasslands compared to agriculture and barren lands and were lower in the presence of livestock grazing. Orthopteran densities were higher and showed strong seasonal dependencies, likely driven by rainfall-mediated vegetation growth during monsoons. Intense grazing and agricultural expansion reduced vegetation biomass and resource availability, which affected the insect populations negatively. These research findings underscore the urgent need to implement ecologically sensitive land management practices, including sustainable grazing regimes and grassland conservation, to maintain insect biodiversity and the broader ecological network. Given the role of insects in ecosystem functioning and their importance to conservation dependent species of, such as the critically endangered Great Indian Bustard (Ardeotis nigriceps), these findings underscore the ecological significance of preserving native grassland habitats in the Thar Desert landscape. Full article

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

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13 pages, 5128 KB

Open AccessArticle

Influence of Host’s Plant Diet on Gut Microbial Communities and Metabolic Potential in Spodoptera frugiperda

by Wan-Ying Dong, Muhammad Hafeez, Sheng-Yuan Zhao, Jin-Ming Zhang, Muhammad Imran, Farman Ullah, Xiao-Wei Li and Yao-Bin Lu

Insects 2025, 16(10), 1042; https://doi.org/10.3390/insects16101042 - 10 Oct 2025

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Abstract

The gut microbiota of insects, shaped by extensive coevolution, plays a crucial role in host adaptability and ecological expansion. The fall armyworm (Spodoptera frugiperda J.E. Smith), a highly polyphagous and migratory invasive pest, infests more than 350 plant species worldwide, resulting in [...] Read more.

The gut microbiota of insects, shaped by extensive coevolution, plays a crucial role in host adaptability and ecological expansion. The fall armyworm (Spodoptera frugiperda J.E. Smith), a highly polyphagous and migratory invasive pest, infests more than 350 plant species worldwide, resulting in substantial crop losses and increased reliance on pesticide applications. In this study, we employed 16S rRNA high-throughput sequencing to investigate diet-induced alternations in the gut microbial communities of larvae fed corn, rice, or an artificial diet. The results showed that diet significantly influenced microbial diversity, with rice-fed larvae exhibiting the highest richness. Firmicutes, Proteobacteria, and Cyanobacteria were the predominant bacterial phyla. Genus-level analysis revealed notable diet-dependent shifts, with Enterobacter and other genera (e.g., Ochrobactrum and Allorhizobium–Neorhizobium–Pararhizobium–Rhizobium) only detected in plant-fed groups. Additionally, current findings suggest that gut microbial genera are more prevalent when S. frugiperda larvae feed on rice plants than on corn plants or an artificial diet and are closely linked to their metabolic activities. Dominant microbial genera are expected to support essential metabolic processes and exhibit increased abundance on rice. These results indicate that the gut microbiome of S. frugiperda is diet-driven reorganization, potentially facilitating its polyphagy. This study extends the current understanding by elucidating the specific gut microbial taxa and their putative metabolic associations that are responsive to diet in S. frugiperda, thereby providing a theoretical basis for its polyphagous capability and underscoring microbiota-based strategies for sustainable pest management. Full article

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

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14 pages, 1815 KB

Open AccessArticle

The Defensin NldefB as a Potential Target for Brown Planthopper Control Based on the Combination of RNA Interference and Fungal Insect Pathogen

by Chen-Ping Lan, Zhi-Guo Hu, Xiao-Ping Yu and Zheng-Liang Wang

Insects 2025, 16(10), 1041; https://doi.org/10.3390/insects16101041 - 10 Oct 2025

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Abstract

Defensins are a class of small cysteine-rich cationic antimicrobial peptides (AMPs) that play vital roles in immune-regulating insect–microbe interaction, offering great potential for developing pest control approaches using RNA interference (RNAi) and insect pathogens. However, the biocontrol potential of defensins from the destructive [...] Read more.

Defensins are a class of small cysteine-rich cationic antimicrobial peptides (AMPs) that play vital roles in immune-regulating insect–microbe interaction, offering great potential for developing pest control approaches using RNA interference (RNAi) and insect pathogens. However, the biocontrol potential of defensins from the destructive rice pest Nilaparvata lugens (brown planthopper, BPH) remains largely unexplored. Here, we identified and functionally characterized a defensin-encoding gene NldefB in BPH. The open reading frame (ORF) of NldefB is 315 bp in length, encoding 104 amino acids with a conserved Knot1 domain. The qRT-PCR results showed that the transcription level of NldefB went upward with the increasing developmental stages, with the highest expressions in the female adults and their fat body. The expression of NldefB was continuously induced by bacterial pathogens but exhibited a pattern of initial increase followed by a decrease when challenged by a fungal pathogen Metarhizium anisopliae. RNAi-mediated silencing of NldefB significantly decreased the host survival rate, egg production and hatchability, as well as the capability to resist fungal infection. Additionally, NldefB suppression resulted in a significant increase in microbial loads. Our findings underscored that NldefB plays essential roles in regulating host development, pathogen defense, and microbial maintenance, providing a potential target for RNAi- and microbe-mediated BPH biocontrol. Full article

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

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16 pages, 2801 KB

Open AccessArticle

Temporal Dynamics of Bacterial Communities in Ectropis grisescens Following Cryogenic Mortality

by Xinxin Zhang, Zhibo Wang, Guozhong Feng, Qiang Xiao and Meijun Tang

Insects 2025, 16(10), 1040; https://doi.org/10.3390/insects16101040 - 9 Oct 2025

Viewed by 181

Abstract

Ectropis grisescens (Lepidoptera: Geometridae) is a destructive pest in tea plantations, leading to significant economic losses through defoliation. Existing control strategies, including chemical insecticides and biological agents, are often limited by environmental concerns, resistance, and variable efficacy. Recent evidence suggests [...] Read more.

Ectropis grisescens (Lepidoptera: Geometridae) is a destructive pest in tea plantations, leading to significant economic losses through defoliation. Existing control strategies, including chemical insecticides and biological agents, are often limited by environmental concerns, resistance, and variable efficacy. Recent evidence suggests that bacteria influence insect physiology and could be leveraged for pest management, but the postmortem microbial ecology of E. grisescens remains uncharacterized. In this study, we employed 16S rRNA sequencing to investigate temporal changes in the bacterial communities of E. grisescens cadavers at 0, 7, and 21 days following cryogenic mortality. Our results indicate a time-dependent decline in microbial diversity, while species richness initially increased before subsequent reduction. The dominant endosymbiont Wolbachia gradually diminished after host death, whereas Enterobacter remained abundant. Notably, non-dominant genera including Lysinibacillus and Sporosarcina exhibited a transient increase in abundance at day 7 before reverting to control levels by day 21. This study presents the first comprehensive analysis of postmortem microbial succession in a lepidopteran system, highlighting dynamic shifts in bacterial composition and offering potential avenues for microbiome-based pest management strategies. Full article

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

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11 pages, 5596 KB

Open AccessArticle

A New Species of Orthosyntexis (Hymenoptera: Anaxyelidae) from Mid-Cretaceous Burmese Amber

by Xiao Li, Gengyun Niu and Meicai Wei

Insects 2025, 16(10), 1039; https://doi.org/10.3390/insects16101039 - 9 Oct 2025

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Abstract

Anaxyelidae, a relict lineage of sawflies, are represented by a single extant species today but displayed remarkable Mesozoic diversity. Here, we describe the Orthosyntexis mascula sp. nov. from mid-Cretaceous Burmese amber. The new species can be readily distinguished by its forewing, with a [...] Read more.

Anaxyelidae, a relict lineage of sawflies, are represented by a single extant species today but displayed remarkable Mesozoic diversity. Here, we describe the Orthosyntexis mascula sp. nov. from mid-Cretaceous Burmese amber. The new species can be readily distinguished by its forewing, with a normally sized, uniformly sclerotized pterostigma; 1-Rs shorter than 1-M; cell 1M more than twice as long as wide; absence of 1r-rs; 1-Cu, distinctly shorter than 2-Cu; 3-Cu shorter than 4-Cu; 2m-cu shorter than 1m-cu; and 3rs-m twice as short as 4-M. In the hind wing, abscissa 2-M+Cu present, 1-M shorter than 2-M, crossvein m-cu absent, and cell R1 closed. Mesotibia with two apical spurs. Examination of high-resolution photographs of Kempendaja jacutensis enables a revised interpretation of its venation, confirming its placement in Anaxyelinae. Comparative analysis of syntexine taxa further reveals that variation in the forewing crossvein 1r-rs consistently corresponds with hind wing venation, suggesting that multiple evolutionary trajectories may have existed within Syntexinae. These findings not only expand the known diversity of Cretaceous Anaxyelidae but also provide new evidence for reconstructing the evolutionary history and internal diversification of Anaxyelidae. Full article

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

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12 pages, 1621 KB

Open AccessArticle

Fitness Trade-Offs and Potential Metabolic Resistance Mechanisms in Geographically Distinct Strains of Trichogramma dendrolimi: Implications for Imidacloprid Resistance Management

by Yu-Tong Li, Xiang-Xin Kong, Wu-Nan Che, Jin-Cheng Zhou, Shu-Qi Wang and Hui Dong

Insects 2025, 16(10), 1038; https://doi.org/10.3390/insects16101038 - 9 Oct 2025

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Abstract

The widespread use of neonicotinoid insecticides has led to increasing resistance in non-target organisms, including the egg parasitoid Trichogramma dendrolimi, a crucial biological control agent. Film-residue bioassays on 17 geographic strains revealed striking inter-strain variability in susceptibility to imidacloprid, with mortality at [...] Read more.

The widespread use of neonicotinoid insecticides has led to increasing resistance in non-target organisms, including the egg parasitoid Trichogramma dendrolimi, a crucial biological control agent. Film-residue bioassays on 17 geographic strains revealed striking inter-strain variability in susceptibility to imidacloprid, with mortality at a discriminating dose of 0.1 mg/L ranging from 25.7% to 87%. The most tolerant (FS) and least tolerant (HA) strains were subsequently selected for evaluation of biological parameters and comparative transcriptomics. Tolerant strains (FS) showed adaptive trade-offs: extended longevity (5.47 ± 0.57 d) and emergence (93.6 ± 1.9%), but reduced fecundity (54.6 ± 4.9 eggs) compared to HA. Transcriptome analysis revealed 2115 differentially expressed genes, with GO enrichment highlighting metabolic and detoxification pathways. KEGG analysis the most enriched pathways were “Protein digestion and absorption” and “Neuroactive ligand-receptor interaction”. RT-qPCR confirmed overexpression of CYP4C1, CYP6K1, and GstS1 in FS, indicating their potential roles in metabolic resistance if present. This study presents preliminary evidence of potential fitness trade-offs and molecular mechanisms that could underly imidacloprid resistance in T. dendrolimi, which may lead to important insights for resistance monitoring and more sustainable integrated pest management strategies. Full article

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

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16 pages, 9701 KB

Open AccessArticle

The Parasitoid Complex of Aleurothrixus floccosus (Hemiptera: Aleyrodidae) in the Citrus Groves of Central–Southern Italy

by Gianluca Melone, Lucia Andretta, Valentino Maria Guastaferro, Eleonora Romito, Giorgio Formisano, Massimo Giorgini and Stefania Laudonia

Insects 2025, 16(10), 1037; https://doi.org/10.3390/insects16101037 - 9 Oct 2025

Viewed by 184

Abstract

The woolly whitefly, Aleurothrixus floccosus, is likely a Neotropical origin species that has spread globally. Introduced to France in 1969, it became a pest in southern European citrus groves, first reported in Italy in 1974. Integrated management using biological control agents is [...] Read more.

The woolly whitefly, Aleurothrixus floccosus, is likely a Neotropical origin species that has spread globally. Introduced to France in 1969, it became a pest in southern European citrus groves, first reported in Italy in 1974. Integrated management using biological control agents is crucial due to the low efficacy of chemical controls. Nymphs produce waxy filaments and honeydew, limiting insecticide contact. Natural enemies, especially from Neotropics, have been documented. The parasitoids Amitus spiniferus and Cales noacki were released in France in 1970 and later observed in Liguria, Italy. In the Campania region, C. noacki was first found on Aleurotuba jelineki in 1984 and this finding preceded the first report of A. floccosus in the same area. Subsequently, C. noacki was also introduced in other regions where it showed better adaptation throughout the Italian territory, reaching high parasitization levels on the woolly whitefly nymphs. After many years since the last field investigations, surveys in 2024–2025 in organic citrus groves in central and southern Italy identified additional parasitoids. Besides C. noacki and A. spiniferus, Eretmocerus paulistus and Signiphora xanthographa were found for the first time in Italy. Both species were originally described from the Neotropical ecozone. The aphelinid finding represents its first documented establishment in Italy, while the signiphorid one represents a new record for the European fauna. E. paulistus is a primary parasitoid, while S. xanthographa is a hyperparasitoid that can limit the effectiveness of other parasitoids. The interaction of these parasitoids resulted in high parasitism rates for A. floccosus nymphs. Preserving the current complexity of parasitoids in integrated pest management (IPM) programs could effectively control the woolly whitefly in central and southern Italy. Full article

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

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20 pages, 2101 KB

Open AccessArticle

Culicidae Fauna (Diptera: Culicomorpha) of the Municipality of Mazagão, Amapá, in the Brazilian Amazon

by Rafael Espíndola do Nascimento, Daniel Damous Dias, Bruna Lais Sena do Nascimento, Tiago Silva da Costa, Raimundo Nonato Picanço Souto, Livia Medeiros Neves Casseb, Joaquim Pinto Nunes Neto and Valeria Lima Carvalho

Insects 2025, 16(10), 1036; https://doi.org/10.3390/insects16101036 - 9 Oct 2025

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Abstract

The Amazon hosts one of the richest diversities of mosquitoes in the family Culicidae, which are key both as arbovirus vectors and as environmental bioindicators. However, the state of Amapá remains poorly studied regarding its mosquito fauna. This study aimed to characterize the [...] Read more.

The Amazon hosts one of the richest diversities of mosquitoes in the family Culicidae, which are key both as arbovirus vectors and as environmental bioindicators. However, the state of Amapá remains poorly studied regarding its mosquito fauna. This study aimed to characterize the diversity and seasonal composition of Culicidae in the municipality of Mazagão, Eastern Amazon, within a rural landscape influenced by human activity and extreme climatic events. Three sampling campaigns were conducted between 2023 and 2024, covering rainy, intermediary, and dry periods. Mosquitoes were collected using Protected Human Attraction (PHA) and CDC light traps at both ground and canopy strata. A total of 3500 specimens were obtained, representing 38 species across 15 genera. The intermediary period yielded the highest abundance and richness, whereas the dry season presented very low diversity, probably because of severe drought and forest fires. Dominant species included Coquillettidia (Rhy.) venezuelensis, Cq. albicosta, and Mansonia titillans. There were significant differences in community diversity between dry and wetter periods, underscoring the strong role of seasonality in shaping mosquito populations. These findings represent the entomofaunistic survey of the region, contributing to biodiversity knowledge and highlighting potential public health risks, thus reinforcing the need for continuous entomological monitoring. Full article

(This article belongs to the Special Issue Biology, Ecology and Management of Mosquitoes Affecting Humans and Animals—2nd Edition)

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13 pages, 1714 KB

Open AccessArticle

Mating Disruption with Biodegradable Dispensers Complemented with Insecticide Sprays Allows an Effective Management of Tuta absoluta in Greenhouse Tomatoes

by Luigi Sannino, Giovanni Benelli, Giulio Piccirillo, Angelo Canale and Andrea Lucchi

Insects 2025, 16(10), 1035; https://doi.org/10.3390/insects16101035 - 9 Oct 2025

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Abstract

IPM approaches based on pheromone-based techniques for the management of the South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), are of great interest. We evaluated the effectiveness of mating disruption (MD) experiments against T. absoluta using a biodegradable pheromone dispenser (Isonet-T TT [...] Read more.

IPM approaches based on pheromone-based techniques for the management of the South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), are of great interest. We evaluated the effectiveness of mating disruption (MD) experiments against T. absoluta using a biodegradable pheromone dispenser (Isonet-T TT BIOX234) in greenhouse-grown tomatoes over two years in southern Italy. A base treatment alternating the most used insecticides for the pest, i.e., the farmer treatment schedule (FTS), was assigned as a reference, and two MD dispenser densities (i.e., 300 and 500 dispensers/ha) were compared with the MD commercial product Isonet T at 1000 units/ha. We conducted two trials on crops at a density of 37,000 plants/ha. Pest flights were monitored in summer–autumn 2023 and 2024 with pheromone-baited Delta traps. The FTS ensured a generally low level of T. absoluta attacks (about 1 leaflet/leaf and 1/300 fruits). Even so, mating disruption resulted in further appreciable reductions in the presence and attacks of the target pest: 89%, 76% and 52% fewer catches; 61%, 45% and 37% fewer mined leaflets; and 76%, 59% and 54% fewer attacked fruits, for Isonet-T TT 500, Isonet-T TT 300 and Isonet T 1000, respectively. Overall, MD biodegradable dispensers could be a valuable tool for controlling T. absoluta in greenhouse-grown tomatoes, while also reducing plastic waste in the agricultural setting. Full article

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

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31 pages, 15340 KB

Open AccessArticle

Integrative Description and Redescription of Black Fly (Diptera: Simuliidae) Species in the Simulium (Gomphostilbia) ceylonicum Species-Group from Thailand

by Sorawat Thongsahuan, Kittipat Aupalee, Afham Yakoh, Domechai Kaewnoi, Wanchai Maleewong, Wichai Srisuka, Anchalee Wannasan, Atiporn Saeung and Hiroyuki Takaoka

Insects 2025, 16(10), 1034; https://doi.org/10.3390/insects16101034 - 8 Oct 2025

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Abstract

Utilizing the COI barcoding approach, cryptic diversity has previously been detected within the morphologically recognized Simulium (Gomphostilbia) trangense Jitklang, Kuvangkadilok, Baimai, Takaoka & Adler, 2008 and S. (G.) sheilae Takaoka & Davies, 1995, of the S. (G.) [...] Read more.

Utilizing the COI barcoding approach, cryptic diversity has previously been detected within the morphologically recognized Simulium (Gomphostilbia) trangense Jitklang, Kuvangkadilok, Baimai, Takaoka & Adler, 2008 and S. (G.) sheilae Takaoka & Davies, 1995, of the S. (G.) ceylonicum species-group. Here, an unknown black fly species belonging to the S. ceylonicum species-group from southern Thailand was discovered and described as a new species, S. (G.) sipoense sp. nov. In addition, S. (G.) trangense is herein fully redescribed based on specimens collected from its type locality. Based on an integrative taxonomic approach combining morphological and molecular data, the validity of the newly described S. sipoense sp. nov. and the redescribed S. trangense is confirmed. Comparative morphological characteristics and phylogenetic analysis, inferred from COI sequences, suggest that the new species is conspecific with the species redescribed as S. trangense, using specimens collected from Malaysia, and is morphologically and phylogenetically closely related to S. sheilae, particularly to the specimens from Indonesia. The redescribed S. trangense is genetically highly similar or even identical to the species that was apparently misidentified as S. sheilae from southern and western Thailand, and is morphologically very similar to the new species, from which it is clearly distinguished by the relative length of the female claw tooth, shape of the male ventral plate, and color of the larval body. A detailed information on the morphological characteristics separates the new species, and the redescribed S. trangense from all other known species of the same species-group in Thailand and neighboring countries is provided. Further studies are warranted to clarify the taxonomic status of several cryptic species recognized within the morphologically defined S. trangense and S. sheilae. Full article

(This article belongs to the Special Issue Diptera Diversity: Systematics, Phylogeny and Evolution)

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31 pages, 10340 KB

Open AccessArticle

Silencing the cyp314a1 and cyp315a1 Genes in the Aedes albopictus 20E Synthetic Pathway for Mosquito Control and Assessing Algal Blooms Induced by Recombinant RNAi Microalgae

by Xiaodong Deng, Changhao He, Chunmei Xue, Dianlong Xu, Juncai Li and Xiaowen Fei

Insects 2025, 16(10), 1033; https://doi.org/10.3390/insects16101033 - 7 Oct 2025

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Abstract

As one of the key vectors for the transmission of Dengue fever, Aedes albopictus is highly ecologically adaptable. The development of environmentally compatible biological defence and control technologies has therefore become an urgent need for vector biological control worldwide. This study constructed and [...] Read more.

As one of the key vectors for the transmission of Dengue fever, Aedes albopictus is highly ecologically adaptable. The development of environmentally compatible biological defence and control technologies has therefore become an urgent need for vector biological control worldwide. This study constructed and used double-stranded RNA (dsRNA) expression vectors targeting the cyp314a1 and cyp315a1 genes of Ae. albopictus to transform Chlamydomonas reinhardtii and Chlorella vulgaris, achieving RNA interference (RNAi)-mediated gene silencing. The efficacy of the RNAi recombinant algal strain biocide against Ae. albopictus was evaluated by administering it to Ae. albopictus larvae. The results showed that the oral administration of the cyp314a1 and cyp315a1 RNAi recombinant C. reinhardtii/C. vulgaris strains was lethal to Ae. albopictus larvae and severely affected their pupation and emergence. The recombinant algal strains triggered a burst of ROS (Reactive Oxygen Species) in the mosquitoes’ bodies, resulting in significant increases in the activities of the superoxide dismutase (SOD), peroxiredoxin (POD) and catalase (CAT), as well as significant upregulation of the mRNA levels of the CME pathway genes in larvae. In the simulated field experiment, the number of Ae. albopictus was reduced from 1000 to 0 in 16 weeks by the RNAi recombinant Chlorella, which effectively controlled the population of mosquitoes. Meanwhile, the levels of nitrogen (N), phosphorus (P), nitrate, nitrite, ammonia and COD (Chemical Oxygen Demand) in the test water decreased significantly. High-throughput sequencing analyses of 18S rDNA and 16S rDNA showed that, with the release of RNAi recombinant Chlorella into the test water, the biotic community restructuring dominated by resource competition caused by algal bloom, as well as the proliferation of anaerobic bacteria and the decline of aerobic bacteria triggered by anaerobic conditions, are the main trends in the changes in the test water. This study is an important addition to the use of RNAi recombinant microalgae as a biocide. Full article

(This article belongs to the Special Issue RNAi in Insect Physiology)

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17 pages, 1534 KB

Open AccessArticle

Improving Telenomus remus (Hymenoptera: Scelionidae) Adoption: Contribution of Different Egg Parasitoid Densities, Fed Adults, and Their Storage for Successful Biological Control of Spodoptera frugiperda (Lepidoptera: Noctuidae)

by Weidson P. Sutil, Adeney de F. Bueno, Leonardo Roswadoski, Rafael S. Iasczczaki, Gabriel S. Carneiro and Yelitza C. Colmenarez

Insects 2025, 16(10), 1032; https://doi.org/10.3390/insects16101032 - 6 Oct 2025

Viewed by 496

Abstract

Egg parasitoids, such as Telenomus remus (Hymenoptera: Scelionidae), face significant challenges after release, as their pupae are exposed to various mortality factors that reduce the efficiency of biological control programs. Therefore, this study aimed to evaluate a honey-solid diet that can feed adults [...] Read more.

Egg parasitoids, such as Telenomus remus (Hymenoptera: Scelionidae), face significant challenges after release, as their pupae are exposed to various mortality factors that reduce the efficiency of biological control programs. Therefore, this study aimed to evaluate a honey-solid diet that can feed adults still inside the capsules without sticking the wasps on its surface, enabling parasitoid storage and later field release. Three independent bioassays were performed, each with 20 completely randomized replications. The first bioassay evaluated the acceptance of a solid feed—honey soaked in cotton thread—compared to the traditional form—honey droplets. In the second bioassay, the storage periods after emergence of adults in capsules with honey-solid food were analyzed at 2, 4, 6, and 8 days post-emergence, and the third bioassay studied the efficacy of different release densities of fed adults under field conditions. Parasitoids fed on the honey-solid diet exhibited a 13.3% reduction in parasitism compared to honey droplets. However, the sticky, viscous nature of honey can lead to parasitoids becoming glued, potentially leading to their death. T. remus feeding on the honey-solid diet resulted in low mortality inside the capsules, living up to six days with only 22.2% reduction in parasitism capacity, making it a viable alternative to release and transport fed adult parasitoids, with an increase of around 30% in the released density of parasitoids compared with the parasitoids fed on honey droplets. This flexibility of releasing T. remus up to six days after emergence provided valuable knowledge to establish T. remus as a biocontrol agent. Furthermore, the highest tested parasitoid density of 20,000 parasitoids per hectare obtained the highest parasitism of Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs. However, future studies are still required with higher releasing densities and less expensive methods of mass rearing the parasitoid for those higher densities to be economically viable. Full article

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

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21 pages, 1771 KB

Open AccessArticle

Laboratory and Semi-Field Cage Demography Studies of Diachasmimorpha longicaudata Mass-Reared on Two Ceratitis capitata Strains

by Lorena Suárez, Segundo Ricardo Núñez-Campero, Silvia Lorena Carta Gadea, Fernando Murúa, Flávio Roberto Mello Garcia and Sergio Marcelo Ovruski

Insects 2025, 16(10), 1031; https://doi.org/10.3390/insects16101031 - 6 Oct 2025

Viewed by 412

Abstract

Ceratitis capitata (Wiedemann) or medfly is a polyphagous pest of fruit crops worldwide. The Asian-native larval parasitoid Diachasmimorpha longicaudata (Ashmead) is mass-reared at the San Juan Biofactory and is currently released for medfly control in Argentina. Information on parasitoid survival, reproduction, and population [...] Read more.

Ceratitis capitata (Wiedemann) or medfly is a polyphagous pest of fruit crops worldwide. The Asian-native larval parasitoid Diachasmimorpha longicaudata (Ashmead) is mass-reared at the San Juan Biofactory and is currently released for medfly control in Argentina. Information on parasitoid survival, reproduction, and population growth parameters is critical for optimizing the mass-rearing process and successfully achieving large-scale release. This study provides a first-time insight into the demography of two population lines of D. longicaudata: one mass-reared on medfly larvae of the Vienna-8 temperature-sensitive lethal genetic sexing strain and the other on larvae of the wild biparental medfly strain. The aim was to compare both parasitoid populations to improve mass-rearing quality and to assess performance on medfly in a semi-arid environment, typical of Argentina’s central-western fruit-growing region. Tests were performed under laboratory and non-controlled environmental conditions in semi-field cages during three seasons. Dl_(Cc-bip) females exhibited higher reproductive potential than did Dl_(Cc-tsl) females under lab conditions. However, both Dl_(Cc-bip) and Dl_(Cc-tsl) were found to be similar high-quality females with high population growth rates in warm–temperate seasons, i.e., late spring and summer. Dl_(Cc-bip) females were only able to sustain low reproductive rates in early autumn, a colder season. These results are useful for improving the parasitoid mass production at the San Juan Biofactory and redesigning parasitoid release schedules in Argentina’s irrigated, semi-arid, fruit-growing regions. Full article

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

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31 pages, 12254 KB

Open AccessArticle

Cryptic and Non-Cryptic Diversity in Cleptoparasitic Bees of the Genus Stelis Panzer, 1806, Subgenus Stelidomorpha Morawitz, 1875, with a Description of New Species from the Arabian Peninsula (Hymenoptera, Megachilidae)

by Max Kasparek, Christian Schmid-Egger and Huw Roberts

Insects 2025, 16(10), 1030; https://doi.org/10.3390/insects16101030 - 6 Oct 2025

Viewed by 829

Abstract

Cleptoparasitic bees of the subgenus Stelis (Stelidomorpha) occur mainly in the Mediterranean and Middle East. In this study, we elevate Stelis aegyptiaca ssp. canaria Warncke, 1992 to species rank (S. canaria Warncke, 1992) and describe two new species, Stelis alainensis [...] Read more.

Cleptoparasitic bees of the subgenus Stelis (Stelidomorpha) occur mainly in the Mediterranean and Middle East. In this study, we elevate Stelis aegyptiaca ssp. canaria Warncke, 1992 to species rank (S. canaria Warncke, 1992) and describe two new species, Stelis alainensis Kasparek sp. nov. and Stelis surica Kasparek sp. nov., both discovered in Oman and the United Arab Emirates. Morphological differences between these species and their closest relatives (S. aegyptiaca Radoszkowski, 1876, S. pentelica Mavromoustakis, 1963, and S. nasuta (Latreille, 1809)) are corroborated by genetic divergence in the mitochondrial COI barcode region, with Kimura 2-parameter (K2P) distances of 7.6–15.2%. A notable case is Stelis nasuta, which shows deep genetic subdivision into three clusters: (1) Iberian Peninsula and North Africa, (2) southeastern France, Italy, and the Balkans, (3) eastern Balkans, Turkey, and the Levant. Moderate genetic K2P distances of 2.9–3.3% complicated species delimitation. Analyses with ABGD, ASAP, bPTP, and RESL algorithms consistently supported recognition of these lineages as putative species. As multivariate analyses of 11 morphometric traits revealed no consistent diagnostic differences, we treat these lineages as phylospecies rather than formal taxa. Our findings demonstrate that bee diversity in the Palaearctic remains underestimated, and that expanded sampling and integrative approaches continue to reveal hidden lineages. Full article

(This article belongs to the Special Issue Bee Conservation: Behavior, Health and Pollination Ecology)

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10 pages, 490 KB

Open AccessArticle

Host Adaptability and Genetic Mechanisms of the Rice Strain of Fall Armyworm (Spodoptera frugiperda)

by Hanyue Wang, Chao Wu, Kenneth Wilson, Yutao Xiao and Kaiyu Liu

Insects 2025, 16(10), 1029; https://doi.org/10.3390/insects16101029 - 6 Oct 2025

Viewed by 408

Abstract

The fall armyworm (Spodoptera frugiperda) is an invasive pest of global concern, posing a significant threat to food security. It can be divided into two biotypes: the rice strain (RS) and the corn strain (CS). These two biotypes are nearly indistinguishable [...] Read more.

The fall armyworm (Spodoptera frugiperda) is an invasive pest of global concern, posing a significant threat to food security. It can be divided into two biotypes: the rice strain (RS) and the corn strain (CS). These two biotypes are nearly indistinguishable morphologically but differ significantly in host adaptability. The two biotypes can hybridize, but the efficiency of their hybridization has not been conclusively determined. Our research has found that the two biotypes of fall armyworm exhibit significant differences in weight gain when feeding on different host plants and artificial diets. The rice strain has a broader diet range, showing notably stronger adaptability to rice and ryegrass compared to the corn strain, suggesting that the rice strain may possess more robust detoxification metabolism. Under laboratory conditions, the two biotypes can hybridize effectively, and their offspring exhibit certain hybrid advantages. The host adaptability traits of the rice strain are dominantly inherited. Our findings provide an important foundation for understanding the biological basis of host adaptability in the rice strain of fall armyworm. Full article

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

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12 pages, 1196 KB

Open AccessArticle

Honey Bee Pollination of Camellia oleifera and Mitigation of Toxic Crop Nectar

by Feng Liu, Pingli Dai, Weiliang Zhou, Jinghua Hu, Fang Yuan, Xijian Xu, Wujun Jiang, Qun Luo, Huijun Huang, Ge Zhang and Wuguang Ye

Insects 2025, 16(10), 1028; https://doi.org/10.3390/insects16101028 - 5 Oct 2025

Viewed by 354

Abstract

Tea oil tree (Camellia oleifera), a woody oil crop native to Southern China, relies on insect pollination for fruit and seed production. However, its nectar is toxic to honey bees (Apis spp.) due to their inability to digest the oligosaccharide [...] Read more.

Tea oil tree (Camellia oleifera), a woody oil crop native to Southern China, relies on insect pollination for fruit and seed production. However, its nectar is toxic to honey bees (Apis spp.) due to their inability to digest the oligosaccharide present in the nectar. This toxicity raises concerns about the trade-off between the benefits of pollination and the risks posed by exposures to toxic nectar. We aimed to investigate whether tea oil tree yield is enhanced by honey bee pollination, while also examining the impact of nectar toxicity and exploring potential mitigation methods. We evaluated the fruit set, seed yield, and oil quality of the crop with or without eastern honey bee (A. cerana) pollination during 2019–2022. We also characterized nectar oligosaccharide compositions collected from both flowers and bee hives. We administered α-galactosidase (an enzyme to promote oligosaccharide digestion) onto bee larvae fed with crop nectar. We found that A. cerana could significantly enhance fruit set and seed yield. The administration of α-galactosidase could enhance larval survivorship challenged by nectar toxicity. The effectiveness of honey bee pollination can vary between years, with warmer temperatures significantly enhancing honey bee pollination benefits. The results suggest that a decision to use honey bees for pollinating tea oil trees should involve consideration of the impact of local weather conditions, as low temperatures may compromise pollination benefits while increasing risks posed by toxic nectar. The administration of digestive enzymes to honey bees shows potential for mitigating natural toxins in tea oil tree nectar. Full article

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

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24 pages, 1879 KB

Open AccessArticle

Comparison of Hard Tick (Acari: Ixodidae) Fauna in Natural and Anthropogenic Habitats in Croatia

by Stjepan Krčmar, Marko Vucelja, Marco Pezzi, Marko Boljfetić, Josip Margaletić and Linda Bjedov

Insects 2025, 16(10), 1027; https://doi.org/10.3390/insects16101027 - 5 Oct 2025

Viewed by 492

Abstract

Due to the evident increase in tick-borne diseases worldwide, it is necessary to constantly update information on the distribution and zoonotic potential of hard ticks. We studied diversity, population structure, and seasonal dynamics of hard tick fauna, faunal similarity and the climate impact [...] Read more.

Due to the evident increase in tick-borne diseases worldwide, it is necessary to constantly update information on the distribution and zoonotic potential of hard ticks. We studied diversity, population structure, and seasonal dynamics of hard tick fauna, faunal similarity and the climate impact on tick occurrence in natural habitats (NHs) (forest communities) and anthropogenic habitats (AHs) (orchards, grasslands, degraded forests) in eastern and central parts of Continental Croatia. Host-seeking hard ticks were sampled by the flag-dragging method in lowland AHs (Bansko Hill (BH); 2023–2024 yr.) and in mountainous NHs (Medvednica Mountain (MM); 2019–2021, 2024 yr.). Overall, 2726 specimens belonging to eight hard tick species (Ixodes ricinus, I. frontalis, I. hexagonus, I. kaiseri, Haemaphysalis inermis, H. concinna, Dermacentor marginatus, D. reticulatus) were identified in AHs, while in NHs 1543 hard ticks, belonging to three species (I. ricinus, I. frontalis, D. reticulatus), were collected. The most abundant species in both habitat types (47.83% in AHs, 99.80% in NHs) was I. ricinus, showing unimodal seasonal activity within studied NHs and bimodal activity at AHs. Comparison of hard tick fauna in different habitats using the Sørenson index on BH and MM showed a high percentage of similarity (50.0–88.8). At AHs, a significant (p < 0.05) negative correlation was determined between the abundance (N) and the mean monthly air temperatures (°C) for H. inermis (r = −0.5931; p = 0.0421) and D. reticulatus (r = −0.6289; p = 0.0285), while their numbers positively correlated (r = 0.5551; p = −0.2667; r = 0.4430; p = 0.1492) with air humidity (%). In contrast, the number of sampled host-seeking I. ricinus ticks at natural forest habitats on MM was positively associated with air temperature and negatively with air humidity at elevations from 200 to 1000 m a.s.l. (r = −0.7684; p = 0.0259; at 200 m a.s.l.). Collected specimens of I. frontalis mark the first record for Osijek–Baranja County, while the sampled D. reticulatus on MM represents the first catch at 1000 m a.s.l. in Croatia. This new data on the distribution and seasonality of medically important hard tick species in Continental Croatia contributes to identifying tick-risk foci and high-risk periods. Full article

(This article belongs to the Topic Ticks and Tick-Borne Pathogens: 2nd Edition)

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34 pages, 40949 KB

Open AccessArticle

New Insight and Confrontation of the Internal Structure and Sensilla of the Mouthparts of Cicadomorpha (Insecta: Hemiptera)

by Jolanta Brożek, Piotr Wegierek, Mick Webb and Adam Stroiński

Insects 2025, 16(10), 1026; https://doi.org/10.3390/insects16101026 - 4 Oct 2025

Viewed by 314

Abstract

This study presents detailed microstructural observations of the mouthparts and sensory organs of adult cicadomorphan species, obtained using scanning electron microscopy (SEM). Despite microstructural variation, the overall morphology of the mouthparts, comprising a three-segmented labium and a bundle of interlocking stylets (maxillae and [...] Read more.

This study presents detailed microstructural observations of the mouthparts and sensory organs of adult cicadomorphan species, obtained using scanning electron microscopy (SEM). Despite microstructural variation, the overall morphology of the mouthparts, comprising a three-segmented labium and a bundle of interlocking stylets (maxillae and mandibles), is highly conserved across species, supporting its evolutionary significance in sap feeding from floem, xylem, or epidermis cells. Variations in the number and shape of mandibular stylet barbs likely reflect adaptations to different host plant tissues. The presence of an identical dual interlocking system between the maxillary stylets, which is found consistently across taxa, enhances functional stability during feeding and indicates a conserved mechanism among cicadomorphans. The species studied exhibit two distinct types of salivary canal closure: hooked and T-shaped. The latter potentially represents a state linked to specialised feeding strategies, such as sap xylem feeding. On the labial tip, there are different shapes of the anterior sensory fields. This area hosts a complex array of sensilla of different numbers, including gustatory (sensilla peg, PS1 and PS2, basiconica, BS3, double basiconica, DB), olfactory (finger–like, FLS) and thermo-hygroreceptive (sensillum dome-shaped, DS, and coeloconicum, CS) types, which facilitate host detection and feeding site selection. In the posterior sensory field, sensilla contact-chemosensory (sensilla basiconica, BS1 and BS2, and sensillum trichoideum, TS) are present. Mechanosensilla chaetica (CH1–CH3) are widely distributed on the last labial segment and may contribute to labium positioning. These findings emphasise the presence of both conserved and specialised morphological traits reflecting evolutionary and ecological diversification within Cicadomorpha. Full article

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

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19 pages, 1585 KB

Open AccessArticle

How Science Supports Honey Bees: Identification of Research on Best Practices in Beekeeping

by Kristina Gratzer, Veronika Musalkova and Robert Brodschneider

Insects 2025, 16(10), 1025; https://doi.org/10.3390/insects16101025 - 4 Oct 2025

Viewed by 909

Abstract

Honey bee health and productivity are strongly linked to management practices and biosecurity measures. We collected and analyzed 744 practice records from 191 peer-reviewed field studies published since 1995, each documenting the impact of a specific hive intervention on colony health or productivity [...] Read more.

Honey bee health and productivity are strongly linked to management practices and biosecurity measures. We collected and analyzed 744 practice records from 191 peer-reviewed field studies published since 1995, each documenting the impact of a specific hive intervention on colony health or productivity parameters. Practices were categorized into good beekeeping practices (n = 128, 17.2%) and biosecurity measures (n = 616, 82.8%) and grouped by management or pathogen theme, geographic region, and season. Most research originated from Europe (34.6%) and North America (33.4%), with nearly all focused on Apis mellifera (99.9%). Varroa control dominated (57.0%), followed by general apiary management (17.2%) and american foulbrood (9.7%). For varroosis, “soft” acaricides such as oxalic and formic acid accounted for 58.5% of records, while “hard” synthetic products represented 21.0%. Within general apiary management, colony management was most frequent (46.9%). For american foulbrood, antibiotics (41.7%) and biotechnical methods (22.2%) were prominent. Tropilaelaps app. treatments relied mainly on “soft” acaricides (81.5%), while small hive beetle control focused on in-hive traps (55.9%). Seasonally, most interventions occurred from August to October, with AFB measures peaking in spring and early summer. The dataset highlights regional research gaps and offers a structured, expandable framework to guide future research and support evidence-based decision-making in beekeeping and advisory services. Full article

(This article belongs to the Special Issue Advances in the Health, Behavior, and Physiology of Honeybees and Other Pollinators)

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19 pages, 4146 KB

Open AccessArticle

Ultrastructure and Transcriptome Analysis Reveal Sexual Dimorphism in the Antennal Chemosensory System of Blaptica dubia

by Yu Zhang, Liming Liu, Haiqi Zhao, Jiabin Luo and Lina Guo

Insects 2025, 16(10), 1024; https://doi.org/10.3390/insects16101024 - 3 Oct 2025

Viewed by 411

Abstract

This study distinguished male and female individuals by wing morphology (males with long wings, females with short wings) and investigated sexual dimorphism in the chemosensory system of Blaptica dubia through integrated ultrastructural and transcriptomic analyses. Scanning electron microscopy (SEM) was used to characterize [...] Read more.

This study distinguished male and female individuals by wing morphology (males with long wings, females with short wings) and investigated sexual dimorphism in the chemosensory system of Blaptica dubia through integrated ultrastructural and transcriptomic analyses. Scanning electron microscopy (SEM) was used to characterize the type, number, and distribution of antennal sensilla, while Illumina HiSeq sequencing, Gene Ontology/Kyoto Encyclopedia of Genes and Genomes (GO/KEGG) annotation, and Quantitative Real-time Reverse Transcription Polymerase Chain Reaction (qRT-PCR) validation were employed to analyze sex-specific gene expression profiles. Both sexes exhibited Böhm’s bristles, chaetic, trichoid, and basiconic sensilla. Males showed significantly more chaetic sensilla on the pedicel and longer type I/II chaetic sensilla on the flagellum, whereas females had longer ST2 sensilla. Basiconic sensilla were predominantly flagellar-distributed and more abundant/longer in males. No sexual differences were observed in Böhm’s bristles. Transcriptomics revealed 5664 differentially expressed genes (DEGs) (2541 upregulated; 3123 downregulated), enriched in oxidation-reduction, extracellular space, lysosome, and glutathione metabolism. KEGG analysis identified five key pathways: lysosome, glutathione metabolism, cytochrome P450-mediated xenobiotic/drug metabolism, and ascorbate/aldarate metabolism. Among 11 chemosensory-related DEGs, chemosensory proteins (CSPs) and odorant binding proteins (OBPs) were downregulated in males, while gustatory receptors (GRs), olfactory receptors (Ors), and ionotropic receptors (IRs) were upregulated. These results demonstrate profound sexual dimorphism in both antennal sensilla morphology and chemosensory gene expression, suggesting divergent sex-specific chemical communication strategies in Blaptica dubia, with implications for understanding adaptive evolution in Blattodea. Full article

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

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19 pages, 1539 KB

Open AccessArticle

Modelling the Effect of Viruses on Insect Survival: Using a Second-Order Phase Transition Model to Describe Time–Effect and Dose–Effect Relationships Using Entomopathogenic Viruses as an Example

by Vladislav Soukhovolsky, Anton Kovalev, Olga Tarasova, Dmitry Kurenshchikov, Yuriy Tokarev, Daria Kharlamova, Yuriy Akhanaev, Sergey Pavlushin and Vyacheslav Martemyanov

Insects 2025, 16(10), 1023; https://doi.org/10.3390/insects16101023 - 3 Oct 2025

Viewed by 362

Abstract

The present study examines the effect of viruses on forest insects depending on the virus dose. Two model approaches are used to quantify the effect of viruses on insect survival. Both approaches describe the processes of virus exposure to insects within the framework [...] Read more.

The present study examines the effect of viruses on forest insects depending on the virus dose. Two model approaches are used to quantify the effect of viruses on insect survival. Both approaches describe the processes of virus exposure to insects within the framework of the second-order phase transition model, which is well known in theoretical physics. The first approach examines the temporal dynamics of larval survival at a given dose of virus exposure. This dependence is characterized by the time–effect curve. In this case, the lethal time of exposure LT100 is the time required for the death of all larvae in the experiment at a given dose D of exposure. The second approach describes the relationship between the proportion q_r of larvae that survived a fixed time T_c after the start of the experiment and the dose D of virus exposure. This dependence is characterized by the dose–effect curve. The experiments tested the effect of two different viruses—nucleopolyhedrovirus (NPV) and cypovirus (CPV)—on such insect species as Lymantria dispar L., Manduca sexta L. and Loxostege sticticalis L. It was shown that the proposed models of second-order phase transitions very accurately (with coefficients of determination of the models close to R² = 0.95) describe experiments on studying the effect of different virus strains on insect survival. The proposed models turned out to be useful for assessing the effectiveness of different virus strains against insect pests. Since the parameters of the second-order “dose–time” and “dose–effect” phase transition models are related to each other, it is possible to reduce the number of measurements of virus–insect interaction due to the relationship between these parameters, and instead of n observations of insect dynamics over time depending on the dose of exposure, the basic parameters characterizing the “virus–insect” interactions can be accurately estimated using only one measurement. It appears that the proposed model can be used to calculate the effect of toxic agents on the population of victims for a wide variety of toxicant species and populations. A sharp reduction in the labor intensity of experiments to assess the toxicity of certain toxicants on animal populations will simplify and reduce the cost of testing the response of living objects to toxicants. Full article

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

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18 pages, 4698 KB

Open AccessArticle

Exploring Potential Distribution and Environmental Preferences of Three Species of Dicranomyia (Diptera: Limoniidae: Limoniinae) Across the Western Palaearctic Realm Using Maxent

by Pasquale Ciliberti, Pavel Starkevich and Sigitas Podenas

Insects 2025, 16(10), 1022; https://doi.org/10.3390/insects16101022 - 2 Oct 2025

Viewed by 531

Abstract

Species distribution models were built for three short-palped crane fly species of the genus Dicranomyia: Dicranomyia affinis, Dicranomyia chorea, and Dicranomyia mitis. The main objective of this study was to assess potential habitat suitability in undersampled regions and explore [...] Read more.

Species distribution models were built for three short-palped crane fly species of the genus Dicranomyia: Dicranomyia affinis, Dicranomyia chorea, and Dicranomyia mitis. The main objective of this study was to assess potential habitat suitability in undersampled regions and explore differences in environmental space. Dicranomyia affinis was historically considered a variety of Dicranomyia mitis due to their morphological similarity. In contrast, Dicranomyia chorea is a widespread species. The biology and ecology of these species remain poorly understood. Models were developed using Maxent, a widely used tool. Our results indicate that Dicranomyia affinis and Dicranomyia chorea share highly similar predicted habitat suitability, with high suitability across the Mediterranean, Central, and Northern Europe, moderate suitability in Eastern Europe, and low suitability in Central Asia. In contrast, Dicranomyia mitis is predicted to have greater habitat suitability in Eastern Europe and Scandinavia, with lower suitability in Mediterranean regions. Analysis of variable importance revealed possible ecological differences between the species. While climatic factors primarily influenced the models for Dicranomyia affinis and Dicranomyia chorea, Dicranomyia mitis was more strongly influenced by the variable pH. These findings may provide insights into potential distributions in undersampled areas and improve our understanding of the species’ ecology. Full article

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

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11 pages, 667 KB

Open AccessArticle

Males of Dalbulus maidis Attract Females Through Volatile Compounds with Potential Pheromone Function: A Tool for Pest Management

by Mateus Souza Sanches, Miguel Borges, Raul Alberto Laumann, Charles Martins Oliveira, Marina Regina Frizzas and Maria Carolina Blassioli-Moraes

Insects 2025, 16(10), 1021; https://doi.org/10.3390/insects16101021 - 2 Oct 2025

Viewed by 683

Abstract

Insects use chemical compounds to communicate with conspecifics and other organisms. The corn leafhopper, Dalbulus maidis (Hemiptera: Cicadellidae) (DeLong & Wolcott), is an important pest in Brazilian maize crops due to its role as a vector of phytopathogens. Despite its economic importance, the [...] Read more.

Insects use chemical compounds to communicate with conspecifics and other organisms. The corn leafhopper, Dalbulus maidis (Hemiptera: Cicadellidae) (DeLong & Wolcott), is an important pest in Brazilian maize crops due to its role as a vector of phytopathogens. Despite its economic importance, the chemical communication between sexes in this species remains to be elucidated. This research aimed to unveil whether D. maidis produces chemical compounds that influence the behavior of the opposite sex and may act as sex pheromones. To evaluate the influence of these volatiles, olfactometer bioassays were conducted as dynamic headspace volatile collections from live insects. Results showed that both male and female leafhoppers emit volatile compounds; however, no sex-specific compounds were detected. Females were attracted to male odors and male aeration extracts, suggesting males produce sex-specific volatiles. Interestingly, males avoided odors from non-acclimated females, which may indicate possible alarm pheromone release. Although the compounds were not identified, this is the first study to demonstrate intraspecific chemical communication in D. maidis mediated by volatiles, and the first such record in Membracoidea. These results contribute to understanding the pest’s biology and support the development of monitoring and control strategies in maize crops. Full article

(This article belongs to the Special Issue Corn Insect Pests: From Biology to Control Technology)

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60 pages, 6956 KB

Open AccessArticle

Integrative Taxonomy Revealed Cryptic Diversity in the West African Grasshopper Genus Serpusia Karsch, 1891 (Orthoptera: Catantopinae)

by Jeanne Agrippine Yetchom Fondjo, Alain Christel Wandji, Reza Zahiri, Oliver Hawlitschek and Claudia Hemp

Insects 2025, 16(10), 1020; https://doi.org/10.3390/insects16101020 - 1 Oct 2025

Viewed by 900

Abstract

Background/Objectives: Despite their ecological significance, DNA barcoding data for African rainforest Orthoptera remain underrepresented globally, limiting progress in species discovery, biodiversity assessment, and conservation. This study aimed to generate molecular data for morphologically identified Serpusia Karsch, 1891 species to evaluate their taxonomic status. [...] Read more.

Background/Objectives: Despite their ecological significance, DNA barcoding data for African rainforest Orthoptera remain underrepresented globally, limiting progress in species discovery, biodiversity assessment, and conservation. This study aimed to generate molecular data for morphologically identified Serpusia Karsch, 1891 species to evaluate their taxonomic status. Methods: Specimens were collected from multiple sites in Cameroon and analyzed using DNA barcoding with COI-5P and 16S rDNA markers. Species delimitation was performed with Automatic Barcode Gap Discovery, and phylogenetic relationships were inferred using Maximum Likelihood and Bayesian Inference. Additionally, external morphology and the male phallic complex were examined. Results: Molecular analyses delineated 19 MOTUs, five corresponding to Serpusia opacula, seven to Serpusia succursor and the remainder to outgroups. Similarity-based assignments matched these MOTUs to 19 BINs. Phylogenetic reconstruction revealed S. opacula and S. succursor as two genetically distinct clades, with the S. opacula group more closely related to Aresceutica Karsch, 1896 than to the S. succursor group. Accordingly, we established a new genus, Paraserpusia gen. nov., to accommodate S. succursor. Within the S. opacula group, five species are recognized: one previously described (S. opacula) and four new species (S. kennei sp. nov., S. missoupi sp. nov., S. seinoi sp. nov., and S. verhaaghi sp. nov.). The former S. succursor, now Paraserpusia succursor, is divided into six well-supported lineages, five of which are formally described here (P. hoeferi sp. nov., P. husemanni sp. nov., P. kekeunoui sp. nov., P. tamessei sp. nov., and P. tindoi sp. nov.). A haplotype network based on COI-5P sequences corroborates three major clades corresponding to the S. opacula group, the S. succursor group, and Aresceutica. Diagnostic morphological differences between Serpusia and Paraserpusia are consistently supported across characters. Conclusions: This integrative approach reveals substantial hidden diversity within Serpusia and highlights the importance of combining molecular and morphological data to uncover and formally describe previously overlooked taxa. Full article

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

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17 pages, 1160 KB

Open AccessArticle

Stability Evaluation of Reference Genes in Gynaephora qinghaiensis (Lepidoptera: Lymantriidae) for qRT-PCR Normalization

by Honggang Li, Fengmei Chang, Xiaoning Cui, Boxin Xi, Guangwei Li, Deguang Liu and Kuiju Niu

Insects 2025, 16(10), 1019; https://doi.org/10.3390/insects16101019 - 1 Oct 2025

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Abstract

The grassland caterpillar Gynaephora qinghaiensis (Lepidoptera: Lymantriidae) is a dominant pest species in the alpine meadows of the Tibetan Plateau. Elucidating changes in key gene expression patterns will provide molecular insights into the adaptive evolutionary mechanisms of insects. Quantitative real-time PCR (qRT-PCR) is [...] Read more.

The grassland caterpillar Gynaephora qinghaiensis (Lepidoptera: Lymantriidae) is a dominant pest species in the alpine meadows of the Tibetan Plateau. Elucidating changes in key gene expression patterns will provide molecular insights into the adaptive evolutionary mechanisms of insects. Quantitative real-time PCR (qRT-PCR) is currently the predominant analytical methodology for assessing gene expression levels. However, variability among samples can compromise result reliability. Thus, selecting stably expressed reference genes for target gene normalization under diverse scenarios is critical. To date, suitable reference genes for G. qinghaiensis under varying experimental conditions have remained unidentified. In this study, the transcriptome data of G. qinghaiensis were obtained using the RNA-seq technique, and 13 candidate reference genes were selected. Four independent algorithms—ΔCt, geNorm, NormFinder, and BestKeeper—as well as a comprehensive online platform, RefFinder, were employed to evaluate the stability under six experimental conditions (tissues, developmental stages, sexes, temperatures, starvation, and insecticide treatments). Our findings identified the following optimal reference gene combinations for each experimental condition: RPS18, RPS15, and RPL19 for tissue samples; RPL19, RPS15, and RPL17 across developmental stages; RPS18 and RPS15 for different sexes; RPS8 and EF1-α under varying temperature conditions; RPL17 and RPL15 during starvation; and RPL19 and RPL17 following insecticide treatments. To validate the feasibility of the reference genes, we examined the expression of the target gene HSP60 in different tissues and under different temperatures. Our results established essential reference standards for qRT-PCR with G. qinghaiensis samples, laying the foundation for precise gene expression quantification in the future. Full article

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

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12 pages, 259 KB

Open AccessReview

Thermal Ecology and Forensic Implications of Blow Fly (Family: Calliphoridae) Maggot Mass Dynamics: A Review

by Akomavo Fabrice Gbenonsi and Leon Higley

Insects 2025, 16(10), 1018; https://doi.org/10.3390/insects16101018 - 1 Oct 2025

Viewed by 665

Abstract

Blow flies (Diptera: Calliphoridae) play a crucial role in the decomposition process and serve as important forensic indicators due to their predictable colonization patterns. This review focuses on the dynamics of maggot masses, highlighting their ecological roles, thermoregulation, and implications for forensics. We [...] Read more.

Blow flies (Diptera: Calliphoridae) play a crucial role in the decomposition process and serve as important forensic indicators due to their predictable colonization patterns. This review focuses on the dynamics of maggot masses, highlighting their ecological roles, thermoregulation, and implications for forensics. We summarize data on the self-organizing behavior of maggot masses, which is influenced by chemical cues and environmental factors. These masses can generate internal temperatures that exceed ambient levels by 10–20 °C, accelerating larval growth and impacting competition among individuals. This localized heating complicates the estimation of the postmortem interval (PMI), as traditional models may not take these thermal influences into account. Furthermore, maggot masses contribute significantly to nutrient cycling and soil enrichment, while the behavior of the larvae includes both cooperation and competition, which is influenced by the species composition present. This review highlights challenges in PMI estimation due to heat production but also discusses advancements in molecular tools and thermal modeling that enhance accuracy. Ultimately, we identify knowledge gaps regarding species diversity, microbial interactions, and environmental variability that impact mass dynamics, suggesting future research avenues that could enhance ecological understanding and forensic applications. Full article

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

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Insects, Volume 16, Issue 10 (October 2025) – 57 articles

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