Insects

16 pages, 1395 KiB

Open AccessArticle

Effects of Parasitism and Venom from the Endoparasitoid Brachymeria lasus on Immunity of the Host Galleria mellonella

by Lijia Peng, Bo Yuan, Jiqiang Song, Fang Wang, Qi Fang, Hongwei Yao and Gongyin Ye

Insects 2025, 16(8), 863; https://doi.org/10.3390/insects16080863 - 19 Aug 2025

Abstract

The pupal endoparasitoid B. lasus injects venom into its host G. mellonella during oviposition, yet knowledge about the venom remains limited. This study explores how parasitism and venom from B. lasus impair the host’s cellular and humoral immunity. At 12–24 h post-parasitization, parasitized [...] Read more.

The pupal endoparasitoid B. lasus injects venom into its host G. mellonella during oviposition, yet knowledge about the venom remains limited. This study explores how parasitism and venom from B. lasus impair the host’s cellular and humoral immunity. At 12–24 h post-parasitization, parasitized G. mellonella pupae had significantly lower total hemocyte counts and also exhibited higher mortality than non-parasitized controls. The proportion of plasmatocytes decreased, while the percentage of granulocytes increased. Parasitism also suppressed in vitro hemocyte spreading, with no significant difference in melanization between parasitized and control groups. Venom treatment significantly inhibited hemocyte spreading and increased cell mortality. Notably, venom-exposed hemocytes showed elevated reactive oxygen species levels and calcium ion concentrations, along with a significant decrease in mitochondrial membrane potential, while caspase 3 activity remained unchanged. These results suggest that both B. lasus parasitism and its venom suppress the cellular immunity of G. mellonella and have strong hemocytotoxic effects. The findings emphasize the role of venom in disrupting host defenses for the development of parasitoid offspring. Full article

(This article belongs to the Special Issue Taxonomy and Phylogeny and Evolution of Parasitic Hymenoptera and Biological Control)

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21 pages, 2606 KiB

Open AccessArticle

Transcriptomics and Metabolomics Combined to Analyze the Response Mechanism of Silkworm Eggs to High-Temperature Stress

by Yang Xiao, Qingrong Li, Zhenbo Sun, Bing Fu, Qiong Yang, Mangui Jiang, Weilong Zhang, Xuhua Huang and Dongxu Xing

Insects 2025, 16(8), 862; https://doi.org/10.3390/insects16080862 - 19 Aug 2025

Abstract

Conventional immediate and high-temperature immediate acid treatment are crucial techniques for breaking the diapause state of silkworm eggs, but their molecular mechanisms remain unclear. This study prepared diapause eggs (CK), conventional immediate acid-treated eggs (46 °C, 5 min, and CG), and high-temperature immediate [...] Read more.

Conventional immediate and high-temperature immediate acid treatment are crucial techniques for breaking the diapause state of silkworm eggs, but their molecular mechanisms remain unclear. This study prepared diapause eggs (CK), conventional immediate acid-treated eggs (46 °C, 5 min, and CG), and high-temperature immediate acid-treated eggs (47.5 °C, 7 min, and GW) and analyzed the transcriptome and metabolome to screen for key expressed genes and key metabolites. Transcriptome results showed that 688, 823, and 222 differentially expressed genes (DEGs) were obtained from CK vs. CG, CK vs. GW, and CG vs. GW, respectively, and 12 DEGs significantly upregulated in all three comparisons (CK vs. CG, CK vs. GW, and CG vs. GW), including glycine-N-methyltransferase, choline dehydrogenase, Hsp68, and Hsp70. The LC-MS analysis results showed that 854, 711, and 506 differential metabolites (DMs) were obtained from CK vs. CG, CK vs. GW, and CG vs. GW, respectively. A total of seven DMs upregulated in all three comparisons and with |log₂Fold Change| ≥ 0.5 in CG vs. GW, including tyrosine-isoleucine-histidine, phenylalanyl-tyrosine, tyrosine-phenylalanine-glutamate-lysine, and histidylleucine, as well as 12 downregulated DMs, were identified. Additionally, it was found that γ-linolenic acid and triglycerides were upregulated in CG vs. GW. The conjoint analysis results revealed that four small peptides, including tyrosine-isoleucine-histidine, phenylalanyl-tyrosine, tyrosine-phenylalanine-glutamate-lysine, and histidylleucine, exhibited a highly significant positive correlation with Hsp70 family genes such as Hsp68 and Hsp70. This suggests that these small peptides, along with γ-linolenic acid and triglycerides, may play a crucial role in the resistance of silkworm eggs to high-temperature stress and the associated oxidative stress. Full article

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

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20 pages, 8352 KiB

Open AccessArticle

Ecological Pest Control in Alpine Ecosystems: Monitoring Asteraceae Phytophages and Developing Integrated Management Protocols in the Three River Source Region

by Li-Jun Zhang, Yu-Shou Ma, Ying Liu and Jun-Ling Wang

Insects 2025, 16(8), 861; https://doi.org/10.3390/insects16080861 - 19 Aug 2025

Abstract

Aster spp., a key grass species for the ecological restoration of alpine degraded grasslands on the Qinghai–Tibet Plateau, often suffers from pest damage during its flowering and seed maturation stages, severely limiting the effectiveness of ecological restoration and the sustainable utilization of germplasm [...] Read more.

Aster spp., a key grass species for the ecological restoration of alpine degraded grasslands on the Qinghai–Tibet Plateau, often suffers from pest damage during its flowering and seed maturation stages, severely limiting the effectiveness of ecological restoration and the sustainable utilization of germplasm resources. This study focused on nine widely distributed species of Aster in the Three River Source Region of Qinghai Province, systematically investigated the structure of arthropod communities and the spatiotemporal dynamics of pests, and developed an integrated pest management (IPM) strategy. Through systematic surveys at multiple sites, a total of 109 arthropod species were identified (57 families of insects, 96 species; 7 families of spiders, 13 species). The Diptera (Tephritidae) and Hemiptera (Miridae) were identified as dominant groups. Tephritis angustipennis was determined to be the key pest, with its population density reaching a peak in mid-to-late August (p < 0.05). Based on the occurrence patterns of the pest, an IPM strategy integrating physical, chemical, and biological control methods was proposed: flower head bagging as a physical barrier significantly reduced plant damage but required balancing the risk of seed sterility. A combination lure (broad-spectrum fruit fly lure + a mixture of sugar and vinegar) showed a significant effect in attracting and killing adult flies. In chemical control, spraying a combination of insecticides (DB: 10% β-Cypermethrin aqueous emulsion (9 mL/acre) + 5% avermectin (20 mL/acre)) during the leaf expansion stage to early flowering stage achieved approximately 80% pest mortality within 24 h; additionally, supplementary spraying of 5% broflanilide (30 mL/acre) during the full flowering stage prolonged the efficacy and delayed the development of insecticide resistance. In terms of natural enemy utilization, Lycosidae and Thomisidae demonstrated significant potential for naturally regulating pest populations. Physiological mechanism studies showed that the difference in responses between plant catalase (CAT) activity and insect glutathione S-transferase (GST) activity was a key factor driving control efficacy (the cumulative explanation rate reached 94%). This IPM strategy, by integrating physical barriers, dynamic trapping, targeted spraying, and natural enemy control, significantly enhances control efficiency and ecological compatibility, providing a theoretical basis and technical paradigm for the ecological restoration of degraded alpine grasslands and the sustainable management of medicinal plants in cold regions. Full article

(This article belongs to the Topic Arthropod Biodiversity: Ecological and Functional Aspects, 2nd Edition)

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20 pages, 3406 KiB

Open AccessArticle

Multigenerational Heat Selection Enhancing Thermal Acclimation and Transcriptional Response of Hsps to Heat Stress in Spodoptera frugiperda Male Adults

by Zhi-Xiao Zhang, Qing-Yi Zhao, Yu Song, Guo-Yun Yu, Wen Fu and Jin Xu

Insects 2025, 16(8), 860; https://doi.org/10.3390/insects16080860 - 18 Aug 2025

Abstract

In this study, using a multigenerational heat selection design, we investigated the possible pattern of thermal acclimation and the background mechanism in Spodoptera frugiperda. Results show that heat selection significantly shortened the larval and pupal developmental duration, which was maintained in the [...] Read more.

In this study, using a multigenerational heat selection design, we investigated the possible pattern of thermal acclimation and the background mechanism in Spodoptera frugiperda. Results show that heat selection significantly shortened the larval and pupal developmental duration, which was maintained in the four tested generations. Significant costs to reproduction were found in the first two generations, but they recovered in the following generations. Heat-selected adults exhibited significantly higher survival rates under extremely high temperatures, and the survival rate increased with subsequent generations. Transcriptomic analysis between heat-selected and non-selected male adults from the first generation showed that heat stress did not induce the upregulation of any heat shock protein (Hsp) genes; in the fourth generation, however, heat stress resulted in the upregulation of a great number of Hsps, indicating a positive correlation between Hsp expression and heat tolerance. Further analysis also found differential expression in other genes associated with heat resistance, such as cuticle-, antioxidant-, and detoxification-related genes. Moreover, quite a number of stress response GO terms were enriched, such as response to heat and other abiotic stimuli. GO enrichment also showed that DEGs were enriched to many more terms related to metabolism. KEGG enrichment revealed that relatively more disease-, metabolism-, and immunity-associated pathways were enriched. The number of disease pathways increased with the selection temperature in the first generation, whereas it decreased with subsequent generations. This study offers new information for the understanding of the thermal acclimation process and mechanism of moth species, and facilitates the prediction and management of this major pest. Full article

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

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19 pages, 1887 KiB

Open AccessArticle

Pathogenicity of Tolypocladium spp. Against Plutella xylostella: Effects on Immune Enzyme Activities and Gene Expression Profile

by Ni Cai, Zhigang Zhang, Babar Hussain Chang, Zhijun Qiao, Fang Liu, Xiangqun Nong and Kaimei Wang

Insects 2025, 16(8), 859; https://doi.org/10.3390/insects16080859 - 18 Aug 2025

Abstract

(1) Background: Tolypocladium spp. are fungi known for producing cyclosporin A and their ability to infect insects. However, their pathogenicity against the lepidopteran pest Plutella xylostella has not been previously reported. (2) Methods: Four Tolypocladium strains were isolated from soil and identified through [...] Read more.

(1) Background: Tolypocladium spp. are fungi known for producing cyclosporin A and their ability to infect insects. However, their pathogenicity against the lepidopteran pest Plutella xylostella has not been previously reported. (2) Methods: Four Tolypocladium strains were isolated from soil and identified through morphological and phylogenetic analyses (ITS, gene sequencing). Growth rates, sporulation capacity, and stress tolerance (45 °C heat, UV) were evaluated. Pathogenicity was assessed via larval bioassays, and immune responses were analyzed by quantifying Toll pathway gene expression and enzyme activities (PO, CAT, POD, GSTs, CarE, AChE) from 24 to 96 h post-inoculation. (3) Results: Strains N8-SF-04092 and O1/O2/O3-SF-04630/04927/04931 were identified as Tolypocladium cylindrosporum and Tolypocladium inflatum, respectively. Strain O2 showed the highest growth rate (p < 0.05), while O3 and N8 exhibited superior sporulation (>7 × 10⁵ spores/mm²). N8 also demonstrated notable thermotolerance. In pathogenicity assays, O1, O3, and N8 caused 98.3%, 93.3%, and 96.7% larval mortality, respectively, with LT₅₀ values (3.89–4.45 days) significantly lower than O2 (p < 0.05). Immune gene expression in P. xylostella was transiently activated at 24 h but suppressed from 48 to 96 h by N8 (p < 0.05), while O1 induced partial activation at 24 h and 96 h but suppression at 48 h and 72 h. Protective enzymes (PO, CAT) were initially upregulated (24–48 h) but inhibited after 72 h (p < 0.01). POD activity showed opposing trends between O1 (initially activated then suppressed) and N8 (initially suppressed then activated). Detoxification enzymes (GSTs, CarE, AchE) were predominantly suppressed, except for GSTs, which increased at 72–96 h. (4) Conclusions: Strains O1 and N8 exhibit high virulence against P. xylostella by disrupting immune responses through dynamic modulation of Toll pathway genes and enzyme activities. The thermotolerance of strain N8 further enhances its promising biocontrol agent for field application. Full article

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

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19 pages, 1451 KiB

Open AccessArticle

Assessing the Productivity of Colonies Headed by Preheated Honeybee Queens

by Abd Al-Majeed Al-Ghzawi, Shahera Talat Zaitoun, Mohammad Nafi Solaiman Al-Sabi, Salem Saleh Mazari, Ilham Mustafa Al-Omari and Maqbool Saed Altalhi

Insects 2025, 16(8), 858; https://doi.org/10.3390/insects16080858 - 18 Aug 2025

Abstract

This study investigated the effects of preheat hardening on the egg-laying capacity of honeybee queens and the flight performance of their daughter workers. A honeybee queen was confined in a cage with a two-section frame for 12 h. Then, 48 h old eggs [...] Read more.

This study investigated the effects of preheat hardening on the egg-laying capacity of honeybee queens and the flight performance of their daughter workers. A honeybee queen was confined in a cage with a two-section frame for 12 h. Then, 48 h old eggs from one section were incubated for 15 min at 41 °C and 70% relative humidity (RH). The queens (n = 12) raised in this section were named the pre-heat-treated queens (pH-TQs). Eggs from the second section were exposed to 34.5 °C and 70% RH for 15 min, and the queens raised in this section were named the non-heat-treated queens (nH-TQs) (n = 12). After mating, both groups were introduced to queenless hives in order to produce workers. The results show that, during the study period (2021 and 2022), the colonies headed by the pH-TQs reared significantly more brood cells and worker adults (especially during the summer), collected and stored more pollen, had less tendency to rear drone brood, and constructed fewer swarm cells than the colonies headed by the nH-TQs. Preheat hardening can be a promising method for improving honeybee workers’ reproductive potential and adaptability, allowing for better adaptation to environmental changes, thus compensating for the mass fatalities of honeybees globally. 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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12 pages, 520 KiB

Open AccessArticle

Evaluation of Bacterial Strains as a Sustainable Approach for Control of Myzus cerasi (F.) (Hemiptera: Aphididae) Under Laboratory and Field Conditions

by Yeşim Bulak Korkmaz

Insects 2025, 16(8), 857; https://doi.org/10.3390/insects16080857 - 18 Aug 2025

Abstract

This study aims to evaluate the insecticidal activity of four bacterial strains against M. cerasi under both laboratory and field conditions, in order to provide a more sustainable and eco-friendly alternative to chemical insecticides. Four environmentally friendly bacterial strains were evaluated for their [...] Read more.

This study aims to evaluate the insecticidal activity of four bacterial strains against M. cerasi under both laboratory and field conditions, in order to provide a more sustainable and eco-friendly alternative to chemical insecticides. Four environmentally friendly bacterial strains were evaluated for their potential as biocontrol agents: Brevibacillus brevis (FD-1), Bacillus cereus (FD-63), Bacillus thuringiensis subsp. kenyae (FDP-8), and Bacillus thuringiensis subsp. kurstaki (FDP-41). Experiments were conducted under both controlled laboratory and field conditions. Data showed that mortality rates ranged from 33.33% to 93.33% under controlled conditions and from 13.33% to 50% under field conditions over the 96 h period. B. thuringiensis subsp. kurstaki (FDP-41) and B. thuringiensis subsp. kenyae (FDP-8) were the most effective bacterial strains against the aphids in controlled conditions. The percentage of mortality related to these applications was 93.33% and 80% in 96 h under laboratory conditions. However, the effectiveness of B. thuringiensis subsp. kurstaki (FDP-41) was 50% at 96 h in the field. These findings suggest that B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. kenyae hold significant potential as biological control agents against M. cerasi. Additionally, FDP-41 showed the lowest LT₅₀ value of 25.37 h in the laboratory and 86.40 h in the field. This indicates a much more rapid and potent effect on M. cerasi compared to other strains. As a result, it was concluded that these bacterial strains may be used successfully as biocontrol agents in the biological control of M. cerasi. Their successful use could reduce reliance on synthetic insecticides, thereby minimizing pesticide residues on crops and contributing to safer agricultural production and environmental sustainability. Full article

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

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19 pages, 1080 KiB

Open AccessArticle

Enhancing Food Production by Sustainable Cricket Farming in Thailand: Evaluating Black Soldier Fly Larvae as a Cost-Effective Feed Ingredient

by Sopa Cansee, Siripuk Suraporn and Nuntawat Butwong

Insects 2025, 16(8), 856; https://doi.org/10.3390/insects16080856 - 18 Aug 2025

Abstract

The high cost of commercial feed presents a major barrier to scaling environmentally responsible cricket (Acheta domesticus) farming, particularly in low-resource settings. We investigated the use of Hermetia illucens (Black Soldier Fly Larvae, BSFL) combined with locally available ingredients to develop [...] Read more.

The high cost of commercial feed presents a major barrier to scaling environmentally responsible cricket (Acheta domesticus) farming, particularly in low-resource settings. We investigated the use of Hermetia illucens (Black Soldier Fly Larvae, BSFL) combined with locally available ingredients to develop affordable, nutritionally balanced feed for A. domesticus. A three-phase experimental approach was used: (i) feed preference assessment from six ingredients; (ii) performance evaluation of four BSFL-to-commercial feed ratios; and (iii) formulation and testing of three practical recipes using Pearson’s square method. Feed efficiency was measured via feed conversion ratio (FCR), efficiency of conversion of ingested food (ECI), and yield. A recipe consisting of 20.6% BSFL, 14.6% soybean meal, 29.1% corn meal, 17.8% rice meal, and 17.8% commercial feed achieved the best performance with an FCR of 2.2, ECI of 44.4%, and juvenile larvae yield of 99.9%. This formulation also reduced feed cost by 33% compared to commercial feed. The study confirmed that integrating BSFL with regionally sourced materials using a simple feed design method can enhance food security, reduce input costs, and support the transition toward circular insect farming systems. Full article

(This article belongs to the Special Issue Insects and Their Derivatives for Human Practical Uses 3rd Edition)

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21 pages, 4423 KiB

Open AccessArticle

Binary Mixtures of Essential Oils: Potent Housefly Adulticides That Are Safe Against Non-Target Species

by Hataichanok Passara, Sirawut Sittichok, Tanapoom Moungthipmalai, Chamroon Laosinwattana, Kouhei Murata and Mayura Soonwera

Insects 2025, 16(8), 855; https://doi.org/10.3390/insects16080855 - 17 Aug 2025

Abstract

In this study, we investigated the insecticidal potential of Eucalyptus globulus Labill. and Cymbopogon citratus Stapf essential oils (EOs), both alone and in synergistic blends with their primary active compounds, against adult houseflies (Musca domestica L.). Toxicity assessments were also conducted on [...] Read more.

In this study, we investigated the insecticidal potential of Eucalyptus globulus Labill. and Cymbopogon citratus Stapf essential oils (EOs), both alone and in synergistic blends with their primary active compounds, against adult houseflies (Musca domestica L.). Toxicity assessments were also conducted on non-target organisms—dwarf honeybees (Apis florea Fabricius) and guppies (Poecilia reticulata Peters)—to evaluate environmental safety. All binary EO mixtures demonstrated superior efficacy compared to individual EOs and the synthetic pyrethroid α-cypermethrin (1% positive control). The most potent formulation, combining 2.5% (v/v) geranial with 2.5% (v/v) E. globulus EO, exhibited a synergistic effect, achieving complete fly mortality (LT₅₀: 0.06 h). This mixture’s mortality index significantly exceeded those of single-component formulations, with a mortality index of 0.22, confirming greater toxicity to flies than α-cypermethrin. Importantly, all the tested EOs and their blends were non-toxic to honeybees and guppies; in comparison, α-cypermethrin caused significant harm. These findings highlight the 2.5% (v/v) geranial + 2.5% (v/v) E. globulus EO blend as a highly effective and environmentally friendly alternative to conventional insecticides. Further research is recommended to optimize its formulation for practical use in sustainable fly management. Full article

(This article belongs to the Special Issue Plant Essential Oils for the Control of Insects and Mites)

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12 pages, 1707 KiB

Open AccessArticle

Characteristics of the Insulin-like Peptide Genes and Their Roles in the Ovarian Development of Zeugodacus cucurbitae (Coquillett)

by Jun-Chen Yi, Chuan-Lian Liu, Dong Chen, Dong Wei and Zhu-Ting Zhang

Insects 2025, 16(8), 854; https://doi.org/10.3390/insects16080854 - 17 Aug 2025

Abstract

The melon fly Zeugodacus cucurbitae (Coquillett) is a globally invasive pest responsible for substantial economic losses in the fruit and vegetable industries. Insulin-like peptides (ILPs) are evolutionarily conserved neuropeptides that play a crucial role in insect reproduction. In this study, six ZcILPs from [...] Read more.

The melon fly Zeugodacus cucurbitae (Coquillett) is a globally invasive pest responsible for substantial economic losses in the fruit and vegetable industries. Insulin-like peptides (ILPs) are evolutionarily conserved neuropeptides that play a crucial role in insect reproduction. In this study, six ZcILPs from the melon fly, designated as ZcILP1–6, were cloned. Phylogenetic analysis demonstrated a strong orthologous link with Dipteran ILPs. Spatiotemporal expression profiling revealed that ZcILP1 and ZcILP3 exhibit preferential enrichment in the adult female fat body, with their expression specifically and significantly upregulated in 5-day-old individuals. Their expression decreased 12, 24, and 48 h post-starvation and increased upon re-feeding. Silencing ZcILP1 and ZcILP3 resulted in reduced ovarian size by 51.42% and 69.17%, respectively. Furthermore, silencing ZcILP1 or ZcILP3 significantly decreased the transcriptional levels of genes downstream of the insulin signaling pathway (ISP), notably the target of rapamycin (ZcTOR) and Forkhead box O (ZcFOXO). Concurrently, the expression of Vitellogenin (ZcVg), a gene associated with reproduction, was significantly downregulated. These findings indicate that ZcILP1 and ZcILP3 regulate ZcVgs expression and ovarian development through ISP, suggesting them as potential targets for green control of Z. cucurbitae. Full article

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

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16 pages, 1311 KiB

Open AccessArticle

Differences in Diversity of Collembola Communities Between Primary and Secondary Forests and Driving Factors

by Mingxin Zheng, Zhijing Xie, Yueying Li, Zhuoma Wan, Haozhe Shi, Liping Wang, Qiaoqiao Ji, Zhaojun Wang and Donghui Wu

Insects 2025, 16(8), 853; https://doi.org/10.3390/insects16080853 - 17 Aug 2025

Abstract

Primary forests harbor extraordinary biodiversity, but conversion from primary forests to secondary forests often leads to biodiversity loss and diminished ecosystem functioning. While much of the existing research has focused on plants and vertebrates, soil fauna—particularly Collembola—remain underexplored in this context. To address [...] Read more.

Primary forests harbor extraordinary biodiversity, but conversion from primary forests to secondary forests often leads to biodiversity loss and diminished ecosystem functioning. While much of the existing research has focused on plants and vertebrates, soil fauna—particularly Collembola—remain underexplored in this context. To address this gap, we conducted a comprehensive assessment of the Collembola diversity and community composition in primary and secondary forests across two regions in northeastern China. Among 5587 Collembola individuals, 69 morphospecies were identified. The Collembola abundance and Shannon–Wiener index were significantly higher in primary forests, although the species richness did not differ significantly between the forest types. In contrast, the community composition differed markedly, with several taxa found exclusively in primary forests. Notably, environmental factors exerted stronger influences on Collembola communities in primary forests, suggesting that these ecosystems may be more vulnerable to climate change and external disturbances. These findings demonstrate that primary forests play a crucial role in protecting soil fauna diversity and emphasize that future conservation efforts should focus on the strict protection of primary forests. Full article

(This article belongs to the Special Issue Arthropods in Ecosystem Resilience: Biodiversity, Distribution, and Conservation Strategies)

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13 pages, 1885 KiB

Open AccessArticle

The Silent Conquest of Aedes albopictus in Navarre: Unraveling the Unstoppable Advance of the Tiger Mosquito Invasion in Progress

by Miguel Ángel González-Moreno, Estrella Miqueleiz-Autor, Itsaso Oroz-Santamaría, Miguel Domench-Guembe and Irati Poveda-Urkixo

Insects 2025, 16(8), 852; https://doi.org/10.3390/insects16080852 - 17 Aug 2025

Abstract

Background: Aedes albopictus, the tiger mosquito, is an invasive exotic species native to Southeast Asia, currently established in Europe, including Spain and the region of Navarre. This vector poses an emerging public health threat due to its ability to transmit dengue, Zika, [...] Read more.

Background: Aedes albopictus, the tiger mosquito, is an invasive exotic species native to Southeast Asia, currently established in Europe, including Spain and the region of Navarre. This vector poses an emerging public health threat due to its ability to transmit dengue, Zika, and chikungunya viruses, which cause diseases in humans. This study presents novel findings by documenting the progression of the invasion of Aedes albopictus in the Navarre region in northern Spain, tracing its status from initial absence to its definitive establishment in certain areas. Methods: Surveillance in Navarre within the LIFE-IP NAdapta-CC project was conducted through a network of strategically placed ovitraps and adult traps to collect eggs and adult mosquitoes. Awareness campaigns and outreach events were organized to inform local authorities and the public about monitoring results and preventive measures. Results: Monitoring confirms Aedes albopictus’ expansion across Navarre despite training, information dissemination, and control efforts, including entomological containment in targeted areas. Conclusions: Eliminating breeding sites remains the most effective strategy to limit its spread. Complete eradication is unlikely given its invasive nature, and the species is expected to expand and colonize at least part of the region in the coming years. Full article

(This article belongs to the Special Issue Surveillance and Management of Invasive Insects)

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22 pages, 4017 KiB

Open AccessArticle

First Attempt at Synthetic Microbial Communities Design for Rearing Gnotobiotic Black Soldier Fly Hermetia illucens (Linnaeus) Larvae

by Laurence Auger, Marie-Hélène Deschamps, Grant Vandenberg and Nicolas Derome

Insects 2025, 16(8), 851; https://doi.org/10.3390/insects16080851 - 17 Aug 2025

Abstract

Previous studies have suggested correlations between the microbiota of the black soldier fly and larval growth and bioconversion ability, primarily through functional inference. However, the concrete impact of the microbiota remains to be demonstrated. To address this, we assembled two synthetic microbial communities [...] Read more.

Previous studies have suggested correlations between the microbiota of the black soldier fly and larval growth and bioconversion ability, primarily through functional inference. However, the concrete impact of the microbiota remains to be demonstrated. To address this, we assembled two synthetic microbial communities (SynComs) derived from endogenous bacteria and evaluated their effects on larval growth. SynComs were administered to axenic larvae reared on sterilised diet (gnotobiotic) or as a probiotic in non-sterile treatments. Larvae were reared on vegetable-based (pre-consumer vegetable residues) or on animal-based (chicken hatchery residues) substrates. The SynComs were administered at two concentrations (5 × 10⁷ and 10⁸ CFU per isolate) in the substrate prior to neonate introduction. SynComs improved the growth of axenic larvae compared to untreated controls, although not to the levels observed in conventionally reared larvae. In non-sterile conditions, the combined SynComs increased growth on vegetable-based substrate, but no effect was observed on the animal-based substrate, suggesting a substrate-dependent effect. These results highlight microbiota’s critical role in larval development and the potential of microbiome engineering in insect rearing systems. This preliminary study opens the way for optimisation of SynCom assemblies, which could be enhanced through pre-testing of individual isolates and selecting microbial combinations tailored to specific substrates. Full article

(This article belongs to the Collection Science of Insect Rearing Systems)

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23 pages, 1657 KiB

Open AccessArticle

High-Precision Pest Management Based on Multimodal Fusion and Attention-Guided Lightweight Networks

by Ziye Liu, Siqi Li, Yingqiu Yang, Xinlu Jiang, Mingtian Wang, Dongjiao Chen, Tianming Jiang and Min Dong

Insects 2025, 16(8), 850; https://doi.org/10.3390/insects16080850 - 16 Aug 2025

Abstract

In the context of global food security and sustainable agricultural development, the efficient recognition and precise management of agricultural insect pests and their predators have become critical challenges in the domain of smart agriculture. To address the limitations of traditional models that overly [...] Read more.

In the context of global food security and sustainable agricultural development, the efficient recognition and precise management of agricultural insect pests and their predators have become critical challenges in the domain of smart agriculture. To address the limitations of traditional models that overly rely on single-modal inputs and suffer from poor recognition stability under complex field conditions, a multimodal recognition framework has been proposed. This framework integrates RGB imagery, thermal infrared imaging, and environmental sensor data. A cross-modal attention mechanism, environment-guided modality weighting strategy, and decoupled recognition heads are incorporated to enhance the model’s robustness against small targets, intermodal variations, and environmental disturbances. Evaluated on a high-complexity multimodal field dataset, the proposed model significantly outperforms mainstream methods across four key metrics, precision, recall, F1-score, and mAP@50, achieving 91.5% precision, 89.2% recall, 90.3% F1-score, and 88.0% mAP@50. These results represent an improvement of over 6% compared to representative models such as YOLOv8 and DETR. Additional ablation studies confirm the critical contributions of key modules, particularly under challenging scenarios such as low light, strong reflections, and sensor data noise. Moreover, deployment tests conducted on the Jetson Xavier edge device demonstrate the feasibility of real-world application, with the model achieving a 25.7 FPS inference speed and a compact size of 48.3 MB, thus balancing accuracy and lightweight design. This study provides an efficient, intelligent, and scalable AI solution for pest surveillance and biological control, contributing to precision pest management in agricultural ecosystems. Full article

(This article belongs to the Special Issue Artificial Intelligence (AI) and Insect Pests Management: Securing Food Security, Human Health, and Natural Resources)

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14 pages, 1014 KiB

Open AccessArticle

The Heat Shock Response Under Natural Conditions in Two Paper Wasp Species

by Astrid Bay Amstrup, Helmut Kovac, Helmut Käfer, Anton Stabentheiner and Jesper Givskov Sørensen

Insects 2025, 16(8), 849; https://doi.org/10.3390/insects16080849 - 16 Aug 2025

Abstract

In a warming world, mechanisms, such as the heat shock response, which plays a role in the recovery from or tolerance towards heat stress, are of increasing importance. Certain heat shock protein genes (hsps) have previously been shown to be highly [...] Read more.

In a warming world, mechanisms, such as the heat shock response, which plays a role in the recovery from or tolerance towards heat stress, are of increasing importance. Certain heat shock protein genes (hsps) have previously been shown to be highly inducible in several paper wasp species during high temperature stress under laboratory conditions. Here, we sought to investigate how hsps are expressed under natural daily temperature fluctuations by collecting broods from wild nests of two species of paper wasps (Polistes dominula, P. nimpha). We collected them at 06:00 and 16:00, the expected low and high points in daily hsp expression, and measured the expression of three hsps (hsp70, hsp83, hsc70). We found that the nest temperature in July could reach temperatures that result in a large upregulation of hsp expression in the laboratory. Under natural conditions, however, we found that the induction response was much more moderate and limited to the larvae. The pupae showed no response to the daily fluctuating temperature and had a constant expression similar to that of larvae in the afternoon. The similarities and differences between natural and laboratory hsp expressions highlight the importance of field studies, as they add valuable context when interpreting laboratory results. Full article

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

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17 pages, 1266 KiB

Open AccessArticle

Living Control Systems: Exploring a Teleonomic Account of Behavior in Apis mellifera

by Ian T. Jones, James W. Grice and Charles I. Abramson

Insects 2025, 16(8), 848; https://doi.org/10.3390/insects16080848 - 16 Aug 2025

Abstract

Self-regulatory foraging behavior in honey bees (Apis mellifera) was investigated using the framework of Perceptual Control Theory (PCT). We developed a PCT-based model to describe how bees maintain goal-directed behavior, specifically targeting a sucrose-rich feeding site while overcoming a wind disturbance. [...] Read more.

Self-regulatory foraging behavior in honey bees (Apis mellifera) was investigated using the framework of Perceptual Control Theory (PCT). We developed a PCT-based model to describe how bees maintain goal-directed behavior, specifically targeting a sucrose-rich feeding site while overcoming a wind disturbance. In a controlled experiment, we found that 13 of 14 bees could successfully adjust their flight paths to overcome the disturbance and consistently reach the feeding target. While they demonstrated a great deal of individual variability regarding how they overcame the wind across experimental trials, they did so by finally adopting a headwind (i.e., flying into the wind) approach pattern rather than tailwind or crosswind approach patterns. These results support the application of PCT to the study of behavior in honey bees, which can be regarded as self-regulative (i.e., non-linear and dynamic) rather than as linear sequences of inputs and outputs. Given that such dynamic models are concerned with the functions or purposes of behavior, they may also be classified as teleonomic. 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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17 pages, 3411 KiB

Open AccessArticle

Pre-Courtship Behavior of Proholopterus chilensis (Coleoptera: Cerambycidae) in a Nothofagus obliqua (Nothofagaceae) Forest

by Diego Arraztio, Amanda Huerta, Ramón Rebolledo, Americo Contreras and Tomislav Curkovic

Insects 2025, 16(8), 847; https://doi.org/10.3390/insects16080847 - 15 Aug 2025

Abstract

The pre-courtship behavior of Proholopterus chilensis on Nothofagus obliqua trees was recorded for the first time, documenting a putative female “calling” behavior and the consequent male “oriented search,” enabling the description of behavioral units, sequences, frequencies, and degrees of stereotypy. Post-resting activity in [...] Read more.

The pre-courtship behavior of Proholopterus chilensis on Nothofagus obliqua trees was recorded for the first time, documenting a putative female “calling” behavior and the consequent male “oriented search,” enabling the description of behavioral units, sequences, frequencies, and degrees of stereotypy. Post-resting activity in both sexes began with walking and grooming during the first hour of the scotophase, following a period of daytime inactivity. Subsequently, females extended their ovipositor both horizontally and vertically, alternating between contact with the tree substrate and, simultaneously, walking the surface (=putative calling behavior), while males became active, extending their antennae perpendicularly to the longitudinal body axis. In response to the putative call, males exhibited oriented flight and hasty walking that followed the trajectory and direction previously taken by females on the substrate, ultimately leading to their location. Statistical analysis of behavioral sequences and the stereotypy index indicated that both behaviors were non-random and partially stereotyped. These findings are consistent with previous chemical analyses of female aerations and terminalia performed by our research group, which identified semiochemicals likely functioning as long-range sex pheromones guiding males to the vicinity of the female’s tree, as well as potential trail pheromones facilitating close-range localization. This dual signaling system seems necessary to the high mobility displayed by females during calling behavior, characterized by frequent and extended bidirectional vertical walks along the trunk, which may enhance signal dispersal and/or reduce predation risk. If confirmed, this would represent a novel sexual encounter mechanism within Cerambycidae. Full article

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

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19 pages, 6481 KiB

Open AccessArticle

Can Sunspot Activity Affect the Population Dynamics of Cotton Bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)?

by Jian Huang and Xiaojun Wang

Insects 2025, 16(8), 846; https://doi.org/10.3390/insects16080846 - 15 Aug 2025

Abstract

Whether there is a correlation between sunspots and an impact on insects has long been a subject of debate. As a worldwide pest, the cotton bollworm can feed on a variety of plants and cause great harm to agriculture. Clarifying the pattern of [...] Read more.

Whether there is a correlation between sunspots and an impact on insects has long been a subject of debate. As a worldwide pest, the cotton bollworm can feed on a variety of plants and cause great harm to agriculture. Clarifying the pattern of sunspots’ influence on it is of great significance for the integrated management of pests. Therefore, we analyzed the sunspot data from 1989 to 2018, as well as the cotton bollworm data from three counties: Maigaiti and Bachu in southern Xinjiang (with 29 and 25 years of data, respectively) and Shawan in northern Xinjiang (with 23 years of data), China. The population size of cotton bollworms increased with the rise in annual mean temperature (T_mean) in the three regions. The impacts of sunspots on annual T_mean in Maigaiti and Bachu were not significant, while in Shawan, there was a lagged effect. Sunspot activity was significantly negatively correlated with the number of moths in Maigaiti and Shawan, while the influence of sunspots on the Bachu population exhibited a certain degree of lag. The fluctuation cycles of moth numbers in these three regions were not consistent with those of sunspots. In Maigaiti and Shawan, the increase in annual, monthly, and daily sunspot numbers was negatively correlated with the rise in annual, monthly, and daily moths captured, respectively, while in Bachu, they were positively correlated. The cycle of sunspots was not synchronized with the cycles of annual T_mean in the three regions. When the number of sunspots exceeded 100, the relative catch (RC) of moths rose in Bachu, while the RC of moths decreased in Maigaiti and Shawan. The RC of moths did not at all increase as the number of sunspots rose. The abrupt changes in the annual T_mean and moth numbers both occurred later than the abrupt change in sunspots, indicating that the influence of sunspots on them had a certain degree of lag and was not synchronous. Full article

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

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Graphical abstract

36 pages, 8266 KiB

Open AccessArticle

Discobola Osten Sacken, 1865 (Diptera, Limoniidae) in China: Taxonomic Review, Updated Distribution, and DNA Barcoding

by Shuo Ma, Liying Dai, Hanhuiying Lv, Yuqing Wei and Xiao Zhang

Insects 2025, 16(8), 845; https://doi.org/10.3390/insects16080845 - 15 Aug 2025

Abstract

The genus Discobola Osten Sacken, 1865 from China is taxonomically reviewed using an integrative approach that combines detailed morphological examination and molecular analysis. Discobola parvispinula (Alexander, 1947), a species widely distributed across the Palaearctic region, is newly recorded from China. Updated distributional data [...] Read more.

The genus Discobola Osten Sacken, 1865 from China is taxonomically reviewed using an integrative approach that combines detailed morphological examination and molecular analysis. Discobola parvispinula (Alexander, 1947), a species widely distributed across the Palaearctic region, is newly recorded from China. Updated distributional data are presented for species known from China: D. annulata (Linnaeus, 1758), D. armorica (Alexander, 1942), D. margarita Alexander, 1924, and D. taivanella (Alexander, 1930). Detailed redescriptions and illustrations, including intraspecific morphological variation, are provided for these species. An identification key to Chinese Discobola species is also presented. Geographical analysis reveals a higher species richness in southern China and the Qinghai–Tibet region, with a progressive decline toward northern and northwestern China. The first DNA barcode reference library for Chinese Discobola is established, comprising 15 mt COI sequences from five species. These sequences, analyzed alongside an additional 101 mt COI sequences from Discobola species in other countries, show that intraspecific divergence within the genus remains below 7.4%, while interspecific divergence ranges from 7.6% to 17.7%. These findings provide important insights into the taxonomy, species delimitation, and biogeography of Discobola in China, contributing to a more comprehensive understanding of Discobola diversity across the region. Full article

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

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