Insects

13 pages, 1222 KB

Open AccessArticle

Effect of Supplementing a Cricket Diet with Cooked Green Beans, a Discarded Agro-Industrial Material, on Performance of Gryllus madagascarensis at Two Rearing Densities

by Tahiry M. Raharimandimby, Tanjona Ramiadantsoa, Hans C. Kelstrup, Sylvain Hugel and Brian L. Fisher

Insects 2026, 17(4), 411; https://doi.org/10.3390/insects17040411 - 10 Apr 2026

Abstract

This study investigated whether cooked green beans, a discarded agro-industrial material, can partially replace commercial chicken feed to improve the performance of the edible cricket Gryllus madagascarensis, while accounting for the strong effects of rearing density. A two-by-two factorial experiment was conducted [...] Read more.

This study investigated whether cooked green beans, a discarded agro-industrial material, can partially replace commercial chicken feed to improve the performance of the edible cricket Gryllus madagascarensis, while accounting for the strong effects of rearing density. A two-by-two factorial experiment was conducted in which crickets were reared at low (500 individuals per box) or high density (2500 individuals per box) and fed either standard chicken feed or the same feed supplemented with cooked green beans, with twenty replicates per treatment. Survival, chicken feed consumption, biomass yield, frass production, efficiency of conversion of ingested feed, and approximate digestibility were measured over the rearing period. Survival increased from 30.0% to 32.9% at low density and from 11.7% to 13.2% at high density, while biomass yield increased from 117.2 g to 129.7 g and from 194.4 g to 231.2 g, respectively. Frass production also increased under supplementation. In contrast, individual body weight was not improved, indicating that higher biomass production resulted mainly from increased survival rather than faster growth. Rearing density remained a major determinant of performance, with low density favoring individual size and survival, and high density maximizing total biomass. Overall, partial replacement of commercial feed with cooked green beans improved survival, biomass yield, and frass production, supporting the use of plant-based wastes to enhance the sustainability of cricket farming. Full article

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

► Show Figures

Figure 1

15 pages, 1408 KB

Open AccessArticle

Small-Scale Habitat Relationships of Corydalus cornutus Hellgrammites in Central Ohio Riffles

by Jon P. Bossley, Peter C. Smiley, Jr. and Hanna E. Humphrey

Insects 2026, 17(4), 410; https://doi.org/10.3390/insects17040410 - 10 Apr 2026

Abstract

Corydalus cornutus hellgrammites are known to inhabit riffles, but information is scarce regarding their habitat relationships at the plot scale and in the northern part of their range in the United States. We investigated the relationship of C. cornutus hellgrammite occurrence, density, and [...] Read more.

Corydalus cornutus hellgrammites are known to inhabit riffles, but information is scarce regarding their habitat relationships at the plot scale and in the northern part of their range in the United States. We investigated the relationship of C. cornutus hellgrammite occurrence, density, and body size with environmental variables at the 1 m² plot scale within central Ohio riffles. We collected hellgrammites and measured hydrological, substrate, large instream wood, and canopy cover variables in nine riffles in 2023 and ten riffles in 2024. Occurrence and density were best predicted by water velocity and grain size score, while none of the measured variables were a good predictor of head capsule width. Occurrence and density increased with increasing water velocity, grain size score, and substrate richness. Density also increased with increases in edge-interior scores. Head capsule width increased with increasing distances to the nearest plot with hellgrammites. Our results suggest that C. cornutus hellgrammites can serve as an indicator species because their occurrence and density reflect the water velocity and substrate conditions within riffles in the Midwestern United States. Full article

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

► Show Figures

Figure 1

15 pages, 1522 KB

Open AccessArticle

Social Wasps and Fruit Exploitation in Brazil: A Synthesis of Species Records, Resource Use, and Management Implications

by Bruno Corrêa Barbosa, Tatiane Tagliatti Maciel, Samanta Brito, Diego Rafael Gonzaga, Guy Smagghe and Rafael Dettogni Guariento

Insects 2026, 17(4), 409; https://doi.org/10.3390/insects17040409 - 10 Apr 2026

Abstract

Social wasps are frequently associated with fruit injuries in agroecosystems, but the diversity of species involved and the ecological context of these interactions remain poorly synthesized in Brazil. This study aimed to compile and analyze records of social wasp interactions with fruits in [...] Read more.

Social wasps are frequently associated with fruit injuries in agroecosystems, but the diversity of species involved and the ecological context of these interactions remain poorly synthesized in Brazil. This study aimed to compile and analyze records of social wasp interactions with fruits in Brazil, combining opportunistic field observations, iNaturalist records, and published studies. In total, 19 field observations, 87 iNaturalist records, and 11 published studies were incorporated into the dataset, resulting in 2443 records involving 51 social wasp species in 10 genera and 36 plant species. Most records involved fruits still attached to the plant (1853; 75.8%), whereas 590 records (24.2%) were associated with fallen fruits. Large-bodied wasps were disproportionately associated with fruits on the plant, while small- and medium-sized species were more frequent on fallen fruits, and this association was significant (χ² = 554.71; p < 0.001). Records also varied significantly throughout the year (χ² = 5693.28; p < 0.001), with peaks in February, March, and July. The interactions were strongly concentrated in a few genera, especially Polybia, Polistes, and Agelaia, and in a few fruit species, particularly Psidium guajava, Anacardium occidentale, and Mangifera indica. Overall, the compiled evidence indicates that fruit exploitation by social wasps in Brazil is structured by body size, resource accessibility, and seasonality. However, because the study compiles heterogeneous records rather than directly measuring economic losses, the agricultural significance of these interactions remains context-dependent and requires further evaluation. Full article

(This article belongs to the Special Issue Hymenoptera in Agroecosystems: Functions, Risks, and Management)

► Show Figures

Figure 1

12 pages, 1273 KB

Open AccessArticle

Logistics-Mediated Artificial Sympatry and Its Implications for Molecular Detection of Hylurgus ligniperda

by Jijing Han, Jiaying Wang, Junxia Cui, Li Liu, Xianfeng Chen, Yuhao Cao, Jiaojiao Chen and Xuemei Song

Insects 2026, 17(4), 408; https://doi.org/10.3390/insects17040408 - 9 Apr 2026

Abstract

International timber trade has accelerated the global spread of the invasive red-haired pine bark beetle H. ligniperda, posing persistent challenges to phytosanitary inspection and border biosecurity. Rapid isothermal amplification assays are increasingly deployed in frontline quarantine settings to support timely regulatory decisions. [...] Read more.

International timber trade has accelerated the global spread of the invasive red-haired pine bark beetle H. ligniperda, posing persistent challenges to phytosanitary inspection and border biosecurity. Rapid isothermal amplification assays are increasingly deployed in frontline quarantine settings to support timely regulatory decisions. However, their performance under the heterogeneous biological backgrounds typical of traded timber remains insufficiently evaluated, particularly with respect to the practical implications of low-level false-positive signals. We re-evaluated a previously reported isothermal assay for H. ligniperda using conditions that simulate timber transport and routine customs workflows. Fifty non-target arthropod species (predominantly insects), selected from quarantine interception records, were included to represent taxa likely to co-occur in operational contexts. Material from Lema decempunctata consistently generated weak but reproducible amplification signals across replicates. Sanger sequencing excluded contamination, confirming low-level non-target amplification in complex biological matrices. Although the signals were faint, ambiguous results in quarantine settings may trigger shipment detention, confirmatory laboratory testing, or temporary trade restrictions, thereby increasing inspection workload, delaying clearance, and generating avoidable compliance costs. These findings indicate that trade-mediated species assemblages can compromise assay performance beyond expectations derived from conventional taxonomy-based specificity testing. To reduce interpretive uncertainty and associated regulatory burden, we propose a tiered diagnostic workflow combining rapid on-site isothermal screening with specificity-oriented SYBR Green qPCR confirmation. This strategy enhances diagnostic reliability while preserving operational efficiency in applied biosecurity surveillance. Full article

(This article belongs to the Special Issue Insect Molecular Biology: From Bioinformatics to Pest Management Applications)

► Show Figures

Figure 1

17 pages, 2593 KB

Open AccessArticle

Activated Charcoal: A Highly Potent Legal Alternative for Vespa velutina Nest Destruction

by Andreas W. M. Presuhn and Ulrich R. Ernst

Insects 2026, 17(4), 407; https://doi.org/10.3390/insects17040407 - 9 Apr 2026

Abstract

The invasive yellow-legged hornet Vespa velutina nigrithorax has spread across Europe following its accidental introduction into France in 2004. This species adversely affects biodiversity, apiculture, pomiculture and viticulture, and human health. Current management relies predominantly on nest destruction; however, manual removal is often [...] Read more.

The invasive yellow-legged hornet Vespa velutina nigrithorax has spread across Europe following its accidental introduction into France in 2004. This species adversely affects biodiversity, apiculture, pomiculture and viticulture, and human health. Current management relies predominantly on nest destruction; however, manual removal is often logistically challenging and costly because nests are typically located high in trees (up to 30 m), frequently necessitating vehicle-mounted lifts. Ground-based application of biocides using long injection lances is comparatively rapid and inexpensive, but in many countries, insecticides are not permitted because the products are not specifically authorized for hornet control. Consequently, alternative approaches are needed. Here, we evaluated the efficacy of activated charcoal for nest destruction in V. v. nigrithorax. We injected 145 nests with 50–100 g of activated charcoal and subsequently destroyed the nests. One week later, we assessed worker survival and the establishment of new nests. Emergency nest construction by surviving workers was observed in three of 145 cases (2.1%). This rate was comparable to that observed following insecticide treatment (two of 136 cases; 1.5%). Activated charcoal therefore appears to be similarly effective to insecticide-based control while offering advantages in terms of environmental compatibility, user safety, ease of handling, and legal applicability in Europe. Activated charcoal may represent a practical alternative to manual nest removal and unauthorized insecticide use. Full article

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

► Show Figures

Figure 1

54 pages, 23221 KB

Open AccessArticle

Soldier Beetle Larvae Are Much More Common in the Fossil Record than Previously Anticipated

by Simon J. Linhart, Carolin Haug, Ana Zippel, Olympia Salvamoser, Patrick Müller and Joachim T. Haug

Insects 2026, 17(4), 406; https://doi.org/10.3390/insects17040406 - 9 Apr 2026

Abstract

Soldier beetle larvae are characterised by numerous very small setae on their body surface, giving them a velvety appearance and hydrophobic properties, and paired gland openings on the segments of the thorax and abdomen for defensive purposes. Only recently, such a larva has [...] Read more.

Soldier beetle larvae are characterised by numerous very small setae on their body surface, giving them a velvety appearance and hydrophobic properties, and paired gland openings on the segments of the thorax and abdomen for defensive purposes. Only recently, such a larva has been recognised in Cretaceous amber. Previously, only two specimens from Baltic amber were known from the fossil record. This provides the impression that such larvae are rare. We report 45 new larval specimens from Eocene Baltic amber and Cretaceous Kachin amber (Myanmar), demonstrating that these fossils are, in fact, more common, but simply not reported. We use the expanded dataset (with fossil and extant larvae and adults, more than 300 specimens) to explore the ontogeny of soldier beetles by quantitatively comparing morphological aspects over time. It appears that there is no major loss in the morphology of adults and larvae. On the contrary, certain larvae known in the modern fauna, so-called pre-larvae, seem absent in the fossil record. Due to the pre-larvae, some modern soldier beetles have certain characteristics of hypermetamorphosis. This type of developmental pattern is also characterised by a distinct change in the direction of the developmental trajectory. However, such a change could not be identified in soldier beetles. Full article

(This article belongs to the Special Issue Fossil Insects: Diversity and Evolutionary History)

► Show Figures

Figure 1

15 pages, 1274 KB

Open AccessArticle

The Relative Contributions of BmPPO and BmDDC in Immune Melanization of Hemolymph in Silkworm, Bombyx mori

by Zunmei Hu, Pan Chen, Chunyang Wang and Ping Chen

Insects 2026, 17(4), 405; https://doi.org/10.3390/insects17040405 - 9 Apr 2026

Abstract

Lepidoptera constitute a major group of agricultural and forestry pests. Therefore, investigating the immune mechanisms of the model species Bombyx mori may provide valuable insights for the development of improved pest management strategies. In insects, phenoloxidase (PO) and dopa decarboxylase (DDC) in immune [...] Read more.

Lepidoptera constitute a major group of agricultural and forestry pests. Therefore, investigating the immune mechanisms of the model species Bombyx mori may provide valuable insights for the development of improved pest management strategies. In insects, phenoloxidase (PO) and dopa decarboxylase (DDC) in immune melanization have been widely studied individually, yet their relative contributions have rarely been investigated. Here, we demonstrate that pharmacological inhibition of either PO or DDC in Escherichia coli-infected larvae significantly suppresses hemolymph melanization, with PO inhibition causing a more pronounced reduction than DDC inhibition. Consistently, RNA interference-mediated knockdown of BmPPO1 or BmPPO2 markedly decreased hemolymph melanization following infection. This results in both PO and DDC contributing to immune-induced hemolymph melanization, with PO playing a dominant role in this process. In contrast, compared to PO inhibition, DDC inhibition leads to significant damage to hemolymph antibacterial activity and cellular immune responses, including hemocyte aggregation, encapsulation, and phagocytosis. In addition, compared with the knockdown of BmPPO1 or BmPPO2, the knockdown of BmDDC leads to a more severe decrease in antibacterial activity and cellular immune function. Exogenous addition of dopamine can partially rescue cell damage, indicating that both DDC and PO play a role in cellular immunity, but DDC has a slightly stronger effect. Overall, this study provides important insights into the immunity of hemolymph in insects and other arthropods. Full article

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

► Show Figures

Figure 1

11 pages, 347 KB

Open AccessArticle

Qualitative vs. Quantitative Damage: Identifying Critical Susceptibility Interval of Common Bean to Euschistus heros (Hemiptera: Pentatomidae)

by Bruna Teixeira Baixo, Adriano Thibes Hoshino, Luciano Mendes de Oliveira, Millena dos Santos Rodrigues, Helter Carlos Pereira, Ayres de Oliveira Menezes Junior and Humberto Godoy Androcioli

Insects 2026, 17(4), 404; https://doi.org/10.3390/insects17040404 - 9 Apr 2026

Abstract

This study evaluated the susceptibility of common bean (Phaseolus vulgaris L.) cultivars to Euschistus heros feeding across various phenological stages. Three cultivars (IPR Curió, IPR Sabiá, and IPR Urutau) were infested with 0.5 insects per plant for eight days starting at anthesis [...] Read more.

This study evaluated the susceptibility of common bean (Phaseolus vulgaris L.) cultivars to Euschistus heros feeding across various phenological stages. Three cultivars (IPR Curió, IPR Sabiá, and IPR Urutau) were infested with 0.5 insects per plant for eight days starting at anthesis and 8, 16, 24, 32, and 40 days after flowering (DAF) using a randomized block design with five replicates. E. heros did not significantly impact grain yield or reproductive abscission, except for the IPR Curió cultivar during flowering, which demonstrated substantial qualitative damage. Feeding injury resulted in increased grain punctures and the grading of commercial classification to Type 2. The most critical susceptibility period occurred during the grain-filling stages (16–24 DAF). IPR Curió was the most sensitive cultivar, exhibiting Type 2 status at both 16 and 24 DAF. These findings demonstrate that although common beans exhibit quantitative tolerance to E. heros at the tested density, qualitative damage during grain development significantly compromises marketability and value. Integrated Pest Management (IPM) should prioritize protecting the crop during mid-to-late reproductive stages to ensure that grain quality standards are met. Full article

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

► Show Figures

Figure 1

19 pages, 2384 KB

Open AccessArticle

Synergistic Antimicrobial and Antiviral Efficacy of Chitosan–Silver Nanocomposites Against Major Pathogens of Bombyx mori: In Vitro and In Vivo Evaluations

by Tao Xu, Zi Liang, Xinhao Jiao, Lulai Wang, Haoran Zhong and Ping Wu

Insects 2026, 17(4), 403; https://doi.org/10.3390/insects17040403 - 8 Apr 2026

Abstract

Diseases caused by pathogenic microorganisms in Bombyx mori have long been a major constraint on the sustainable development of sericulture. Current preventive strategies remain substantially constrained by issues of drug resistance and environmental compatibility. In recent years, the application of nanomaterials for pathogenic [...] Read more.

Diseases caused by pathogenic microorganisms in Bombyx mori have long been a major constraint on the sustainable development of sericulture. Current preventive strategies remain substantially constrained by issues of drug resistance and environmental compatibility. In recent years, the application of nanomaterials for pathogenic microorganism control has garnered escalating attention. Among these, chitosan–silver nanoparticles (CS-Ag NPs), as an emerging class of nanocomposites, integrate the biocompatibility and biodegradability of chitosan with the robust antimicrobial activity of silver nanoparticles, thereby exhibiting considerable potential for preventing pathogenic infections. Nevertheless, the efficacy of CS-Ag NPs against B. mori pathogens has not previously been documented. In this study, CS-Ag NPs were successfully synthesized via chemical reduction. Their antiviral activity was validated using quantitative PCR. The inhibitory efficacy of CS-Ag NPs against Bacillus bombysepticus and Serratia marcescens was evaluated through in vitro inhibition zone assays and bacterial growth curve analysis, with the minimum inhibitory (MIC) concentration for both pathogens determined. Notably, CS-Ag NPs exhibited no significant inhibitory effect on filamentous fungi, potentially due to the impaired ability of nanoparticles to penetrate fungal cell walls. Preliminary mechanistic investigations into the antimicrobial mechanism of CS-Ag NPs were conducted from the perspectives of oxidative stress. Our data showed that CS-Ag NPs could effectively alleviate ROS accumulation induced by the pathogen. In summary, our work systematically investigates the potential of CS-Ag NPs in controlling pathogens and enables the preliminary elucidation of their antibacterial mechanisms. These findings establish a theoretical foundation for the development of pharmaceuticals against pathogenic microorganisms and also offer novel insights into the ecofriendly management of diseases. Full article

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

► Show Figures

Figure 1

22 pages, 1757 KB

Open AccessArticle

Acute Effects of a Moderate Static Magnetic Field on Gypsy Moth (Lymantria dispar) Larvae

by Dajana Todorović, Marija Mrdaković, Larisa Ilijin, Milena Vlahović, Milena Janković-Tomanić, Dragana Matić, Aleksandra Filipović and Vesna Perić-Mataruga

Insects 2026, 17(4), 402; https://doi.org/10.3390/insects17040402 - 8 Apr 2026

Abstract

Magnetic fields are abiotic environmental factors that can cause a wide range of biological effects at both the cellular and whole-organism levels. In this study, we investigated the effects of a static magnetic field (SMF, 110 mT) on life history traits and antioxidant [...] Read more.

Magnetic fields are abiotic environmental factors that can cause a wide range of biological effects at both the cellular and whole-organism levels. In this study, we investigated the effects of a static magnetic field (SMF, 110 mT) on life history traits and antioxidant defence mechanisms during the preadult development of Lymantria dispar. SMF exposure did not affect the mass of younger larvae, whereas older larvae and pupae showed significantly reduced mass compared to controls. Estimated larval mortality was higher in the SMF group, while developmental duration was significantly prolonged in the fifth larval instar and in both male and female pupae. SMF induced stage-dependent modifications in antioxidant defence. Superoxide dismutase activity and catalase activities were significantly increased, predominantly in later developmental stages, while glutathione reductase and glutathione S-transferase showed instar-dependent responses. In addition, the content of total and oxidised glutathione was significantly higher in the fifth and sixth instars of SMF-exposed larvae compared to controls. The study shows that static magnetic field exposure can interfere with normal developmental processes and redox homeostasis in insects, implying potential adaptive mechanisms under stressful conditions. Full article

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

► Show Figures

Figure 1

18 pages, 5385 KB

Open AccessArticle

Time-Course Transcriptomic Analysis of Early Host Responses to Oral SfMNPV Challenge in Spodoptera frugiperda Larval Midgut

by Lin Guo, Wenyi Jin, Yan Tong, Huixian Shi, Qin Kang, Jihong Zhang, Qian Meng, Xuan Li, Hongtuo Wang, Qilian Qin and Huan Zhang

Insects 2026, 17(4), 401; https://doi.org/10.3390/insects17040401 - 8 Apr 2026

Abstract

The fall armyworm (Spodoptera frugiperda) is a major global migratory pest. Its increasing insecticide resistance poses a severe threat to food security. Developing biopesticides such as SfMNPV is critical for sustainable control. Nevertheless, the early molecular mechanisms underlying the S. frugiperda [...] Read more.

The fall armyworm (Spodoptera frugiperda) is a major global migratory pest. Its increasing insecticide resistance poses a severe threat to food security. Developing biopesticides such as SfMNPV is critical for sustainable control. Nevertheless, the early molecular mechanisms underlying the S. frugiperda midgut response to oral SfMNPV challenge remain poorly understood. This study utilized high-throughput transcriptome sequencing to systematically characterize the dynamic transcriptional profiles of the larval midgut at 1, 12, and 24 h after oral SfMNPV inoculation. Results showed that the midgut transcriptional response to SfMNPV is time and stage-specific. During this period, the physical midgut barrier underwent remodeling, with core components of the peritrophic matrix downregulated at 1 h, followed by the basal lamina at 12 h, alongside the activation of cytoskeleton genes during 12–24 h. Concurrently, sustained endoplasmic reticulum stress, autophagy, and ubiquitin system responses occurred from 12 to 24 h. At the metabolic level, the defense system exhibited a functional succession, shifting from ABC transporters and UDP-glycosyltransferases at 1 h to glutathione S-transferases and superoxide dismutase at 12–24 h. Additionally, the midgut tissue exhibited a cascade transition from pro-apoptotic signaling at 1 h to compensatory regenerative repair mediated by the Wnt, mTOR, and Hippo pathways at 12–24 h. This study elucidates the molecular process of barrier damage, homeostatic imbalance, and tissue remodeling during early oral SfMNPV challenge. These findings provide a global perspective on baculovirus-host interactions and establish a theoretical foundation for designing novel biopesticides targeting the midgut interaction. Full article

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

► Show Figures

Figure 1

12 pages, 1814 KB

Open AccessArticle

Prevalence of Same-Sex Sexual Behavior in Termites: Persistence Under Mate-Seeking Stress Absence

by Yong-Hui Wang, Huan Wang, Jia Wu, Bei Du, Ya-Lin Xiao, Xin-Yue Li and Ya-Nan Dong

Insects 2026, 17(4), 400; https://doi.org/10.3390/insects17040400 - 8 Apr 2026

Abstract

Same-sex sexual behavior is an enigma in behavioral ecology as it does not result in reproduction. Previous studies on the evolution of same-sex sexual behavior have primarily focused on factors such as recognition mechanisms, resource constraints, and challenges in securing an opposite-sex partner, [...] Read more.

Same-sex sexual behavior is an enigma in behavioral ecology as it does not result in reproduction. Previous studies on the evolution of same-sex sexual behavior have primarily focused on factors such as recognition mechanisms, resource constraints, and challenges in securing an opposite-sex partner, while overlooking the investigation into active same-sex sexual behavior without environmental stress. Here, through experimentation, we investigated the stability of same-sex pairs in tandem running, the mating behavior of pairs that form same-sex tandem runs, and the occurrence of same-sex sexual behavior (SSB) when opposite-sex partners are available. Results indicated that while the stability of same-sex tandems is lower than that of opposite-sex tandems, both males and females are capable of expressing sex-specific behaviors typical of the opposite sex and forming same-sex tandems. Notably, SSB was observed not only in same-sex pairing contexts but also when individuals had the autonomy to choose between same-sex and opposite-sex partners. These results demonstrate that same-sex sexual behavior in termites is not a behavioral response to environmental stress (e.g., the absence of opposite-sex partners) but rather an actively expressed behavior. These findings highlight the role of sex role plasticity in the evolution of same-sex sexual behavior, providing a new mechanistic perspective for understanding same-sex sexual behavior in social insects. Full article

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

► Show Figures

Figure 1

22 pages, 2510 KB

Open AccessArticle

Tree Plantation-Driven Forest Fragmentation Reduces Ground-Dwelling Insect Diversity Through Cascading Declines in Seedling Density

by Zhenyan Zhang, Chaoyou Jiang, Xinyu Zhu and Fengqun Meng

Insects 2026, 17(4), 399; https://doi.org/10.3390/insects17040399 - 7 Apr 2026

Abstract

The global expansion of tree plantations has led to extensive fragmentation of natural forests, posing significant challenges for biodiversity conservation. Understanding the diversity patterns and underlying mechanisms of ground-dwelling insects in these fragmented landscapes is critical to inform effective conservation strategies. To address [...] Read more.

The global expansion of tree plantations has led to extensive fragmentation of natural forests, posing significant challenges for biodiversity conservation. Understanding the diversity patterns and underlying mechanisms of ground-dwelling insects in these fragmented landscapes is critical to inform effective conservation strategies. To address this, we sampled ground-dwelling insects using pitfall traps across nine remnant natural forest fragments (“islands”) embedded within a tree plantation matrix in Guangxi, China. We examined insect family-level diversity and community composition in relation to fragment isolation (low vs. high) and size (large vs. small) and explored the mechanisms driving the observed patterns. Our results revealed no significant difference in ground-dwelling insect diversity between low-isolation and high-isolation fragments. However, diversity was significantly lower in smaller fragments compared to larger ones. This reduction was primarily driven by decreased seedling density within smaller fragments, directly reflecting the adverse effects of plantation-driven fragmentation on native seedling establishment. Furthermore, we observed noble shifts in community composition of ground-dwelling insects along both fragment isolation and size gradients. Highly isolated fragments exhibited a decline in phytophagous insects and omnivores (with detritivore-herbivore diets), but an increase in detritivores. Smaller fragments exhibited consistent declines across multiple insect taxa spanning various dietary guilds. The observed changes in ground-dwelling insect composition were driven by shifts in plant (especially seedling) community composition. Our findings reveal a clear cascading effect: plantation-driven fragmentation limits native plant regeneration, and these limitations subsequently propagate to higher trophic levels, profoundly impacting ground-dwelling insects. Effective restoration of plantation-fragmented landscapes requires strategies that both prioritize the preservation of large, continuous forest fragments and promote native seedling recruitment within existing fragments. Full article

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

► Show Figures

Figure 1

20 pages, 2742 KB

Open AccessArticle

The Expansion of Dirofilaria repens in the Irtysh Basin of Western Siberia Is Associated with Nine Species of Aedes Mosquitoes

by Vladimir A. Burlak, Tatyana A. Khlyzova, Valentina S. Fedorova, Yuliya V. Andreeva, Svetlana S. Alekseeva, Dmitry A. Karagodin, Igor V. Sharakhov, Maria V. Sharakhova and Gleb N. Artemov

Insects 2026, 17(4), 398; https://doi.org/10.3390/insects17040398 - 7 Apr 2026

Abstract

The northward expansion of Dirofilaria spp. is a current medical and veterinary concern. However, it is unclear how far north the parasite has spread in Western Siberia and what species of mosquito can carry and transmit it. This study examined Dirofilaria spp. infection [...] Read more.

The northward expansion of Dirofilaria spp. is a current medical and veterinary concern. However, it is unclear how far north the parasite has spread in Western Siberia and what species of mosquito can carry and transmit it. This study examined Dirofilaria spp. infection in Aedes mosquitoes in the taiga zone of the Irtysh Basin. The mosquito species were identified based on morphology, and Dirofilaria spp. were identified using PCR. Of the 13 habitats surveyed, 24 of 2205 mosquito samples were infected with D. repens and 1 with Dirofilaria sp. The highest infection rate (~7.6) was recorded in Tobolsk, Tyumen region, at 58.4° N. Mosquito infection was recorded as far north as 61° N in Khanty-Mansiysk. The presence of the infective L3 stage of the parasite was recorded up to 60° N in Bobrovsky. Nine species of mosquitoes were found to be infected with D. repens: Aedes rossicus, Aedes behningi, Aedes cantans, Aedes communis, Aedes cyprius, Aedes euedes, Aedes excrucians, Aedes flavescens, and Aedes sticticus. Two of these species, Ae. behningi and Ae. communis, were competent vectors of the parasite. Thus, D. repens has successfully adapted to the Aedes mosquito in the taiga zone of Siberia. Full article

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

► Show Figures

Figure 1

17 pages, 1405 KB

Open AccessArticle

Evaluation of Predation on Phytophagous Insects by a Phytozoophagous Mirid Bug, Apolygus lucorum

by Lili Wang, Baoyou Liu and Kongming Wu

Insects 2026, 17(4), 397; https://doi.org/10.3390/insects17040397 - 7 Apr 2026

Abstract

Apolygus lucorum, a phytozoophagous mirid bug, plays an important role in the species interactions within fruit tree and cotton ecosystems. Previous research has mainly focused on the phytophagous damage that it causes to crops, while its role as a predator of arthropods [...] Read more.

Apolygus lucorum, a phytozoophagous mirid bug, plays an important role in the species interactions within fruit tree and cotton ecosystems. Previous research has mainly focused on the phytophagous damage that it causes to crops, while its role as a predator of arthropods remains poorly understood. In this study, we systematically investigated the functional responses of A. lucorum to three crop pests: eggs of Helicoverpa armigera, nymphs of Aphis gossypii, and nymphs of Bemisia tabaci. The results show that the predatory behavior of A. lucorum towards all three prey species followed a Holling type II functional response model. Predatory performance varied significantly depending on prey species, developmental stage, and sex of the mirid. The theoretical maximum predation rate was highest for A. gossypii (833.33 individuals/day) and lowest for B. tabaci nymphs. Adult mirids and older nymphs (4th instar) exhibited higher predation rates than younger nymphs. Field-collected A. lucorum from Bt cotton fields were analyzed using molecular diagnostics, and the result confirmed natural predation on A. gossypii, which was consistent with observed pest occurrence patterns in the field. Overall, this study clarifies the prey selectivity and stage-dependent predatory strategies of A. lucorum, providing insights into its trophic flexibility as a facultative predator. These findings contribute to a more comprehensive understanding of its ecological role in agricultural ecosystems, but do not support its use as a biological control agent given its predominantly phytophagous nature and documented pest status. Full article

(This article belongs to the Special Issue Biosystematics and Management of True Bugs (Hemipterans))

► Show Figures

Graphical abstract

13 pages, 1191 KB

Open AccessArticle

From Waste to Resource: Performance of Black Soldier Fly Larvae Reared on Restaurant Food Waste at an Industrial Scale

by Joana Oliveira, Carolina Ligeiro, Rafaela Fantatto, Clarice Silva e Souza, Maria Ana Machado, Leonardo Gaston Guilgur, Alexandre Trindade, Ricardo Assunção and Daniel Murta

Insects 2026, 17(4), 396; https://doi.org/10.3390/insects17040396 - 5 Apr 2026

Abstract

Food waste poses significant environmental, economic and public health challenges. The black soldier fly (Hermetia illucens) larvae (BSFL) represent a promising solution for organic waste valorisation, converting substrates into protein-rich biomass for animal feed and organic fertiliser. However, the use of [...] Read more.

Food waste poses significant environmental, economic and public health challenges. The black soldier fly (Hermetia illucens) larvae (BSFL) represent a promising solution for organic waste valorisation, converting substrates into protein-rich biomass for animal feed and organic fertiliser. However, the use of food waste as an insect substrate remains prohibited in the European Union due to regulatory and safety concerns. This study evaluated the suitability of heterogeneous food waste for BSFL rearing under industrial conditions by comparing larval performance on a standard Gainesville diet (control) and a blend derived from local restaurant waste (test). The 14-day bioconversion assay assessed bioconversion rate (BCR), feed conversion ratio (FCR), survival rate, average growth rate, and nutritional composition. Compared with the control, the test group showed significantly improved (p < 0.001) BCR (18.34% vs. 11.02%), FCR (5.48 vs. 9.09 kg/kg), survival (69.29% vs. 51.30%), and growth (8.38 vs. 6.59 mg/day). Larvae reared on food waste also exhibited significantly higher protein (19.70% vs. 16.80%), fat (13.70% vs. 7.20%), ash (6.97% vs. 3.51%), carbohydrates (7.00% vs. 3.60%), and fibre (5.20% vs. 2.90%). Overall, heterogeneous food waste is a suitable substrate for BSFL, supporting agrifood sustainability; however, future research should focus on standardisation of these substrates. Full article

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

► Show Figures

Graphical abstract

14 pages, 1375 KB

Open AccessArticle

Molecular Identification of Palmistichus elaeisis, Tetrastichus howardi, Trichospilus diatraeae and Trichogramma pretiosum (Hymenoptera: Chalcidoidea)—Important Biocontrol Agents

by Izabella de Lima Palombo, Fabricio Fagundes Pereira, André Pessoa da Costa, Patrik Luiz Pastori, Alex Polatto Carvalho, Andrea Renata da Silva Romero, André Vieira do Nascimento, Ana Maria Perez Obrien, Patricia Iana Schmidt, Carlos Reinier Garcia Cardoso and Marcelo Teixeira Tavares

Insects 2026, 17(4), 395; https://doi.org/10.3390/insects17040395 - 5 Apr 2026

Abstract

Parasitoid wasps play a fundamental role in the biological control of pests. However, their morphological identification may be limited due to their small size and the high morphological similarity between species. Our objective was to identify specific genomic variants of the target species [...] Read more.

Parasitoid wasps play a fundamental role in the biological control of pests. However, their morphological identification may be limited due to their small size and the high morphological similarity between species. Our objective was to identify specific genomic variants of the target species Palmistichus elaeisis Delvare & LaSalle, 1993, Tetrastichus howardi (Olliff, 1893), Trichospilus diatraeae Cherian & Margabandhu, 1942, and Trichogramma pretiosum Riley, 1879, (Hymenoptera: Chalcidoidea) by whole-genomic sequencing. Parasitoids were collected from their hosts and established in the laboratory after adult emergence. A sample of each parasitoid was sent to the Departamento de Ciências Biológicas at Universidade Federal do Espírito Santo (UFES) and “Oscar Monte” Entomophagous Insect Collection for morphological identification. Subsequently, samples composed of 20 individuals were preserved in absolute ethanol for DNA extraction. The DNA was extracted, quantified and sequenced on the Illumina Novaseq 6000 platform. Bioinformatic tools were used for quality control, detection of specific genomic variants, principal component analysis (PCA), and support vector machine (SVM). Genomic sequencing generated high-quality data for the analyzed parasitoids, allowing the identification of four specific variants for P. elaeisis, two for Te. howardi, four for Ts. diatraeae and five for Tg. pretiosum. These results provide a precise molecular tool for distinguishing parasitoids used in biological control programs. Full article

(This article belongs to the Special Issue Insect Molecular Biology: From Bioinformatics to Pest Management Applications)

► Show Figures

Graphical abstract

17 pages, 1802 KB

Open AccessArticle

Effects of Continuous Exposure to Yellow Light on the Behavior and Longevity of Anomala corpulenta

by Yueli Jiang, Xiaoguang Liu, Zhongjun Gong, Yuqing Wu, Li Qiao, Ruijie Lu, Jing Zhang, Jin Miao and Tong Li

Insects 2026, 17(4), 394; https://doi.org/10.3390/insects17040394 - 4 Apr 2026

Abstract

Anomala corpulenta (Motschulsky, 1854) (Coleoptera: Scarabaeidae), an important agricultural and forestry pest, is a beetle widely distributed in many countries, inflicting damage on numerous crops. Given the limited selectivity of commonly used light trapping devices for insects and their potential adverse effects on [...] Read more.

Anomala corpulenta (Motschulsky, 1854) (Coleoptera: Scarabaeidae), an important agricultural and forestry pest, is a beetle widely distributed in many countries, inflicting damage on numerous crops. Given the limited selectivity of commonly used light trapping devices for insects and their potential adverse effects on the ecological environment, there is a pressing need for innovative light control methods. This study investigates the effects of continuous exposure to yellow light on the behavioral activities of A. corpulenta adults, which are nocturnal. The experimental setup comprised a light experimental group (exposed continuously to yellow light at wavelengths of 565–585 nm and intensities of 30–40 lx at night) and a control group (kept in a dark room). Observations were made on emergence, mating, feeding, and mortality. Results showed that continuous exposure to yellow light significantly alters the emergence rhythm of A. corpulenta, leading to delays and dispersions in peak emergence, with emergence occurring during the light period. The emergence rates varied significantly from the control group during specific periods, and the overall emergence rate was notably affected, with female insects exhibiting greater sensitivity. Furthermore, food consumption and the number of mating pairs were significantly lower compared to the control group. Continuous exposure to yellow light also influenced the longevity of A. corpulenta; in the mixed test group, female insects had a lifespan of 20 days, while males lived for 18 days. In the sexually isolated test group, both sexes died within 16 days, with the survival rates of the experimental group being lower than those of the control group on certain days. This study concludes that continuous exposure to yellow light significantly modifies the emergence rhythm of A. corpulenta, while reducing the emergence rate, total food intake, and the number of mating pairs. Notably, in the mixed-sex test group, the survival probability of females in the experimental group was significantly lower than that of the control group. These findings provide a theoretical foundation for the light control of A. corpulenta and contribute to the field of insect visual ecology. Full article

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

► Show Figures

Figure 1

16 pages, 3754 KB

Open AccessArticle

Microstructural Analysis of Termite Wings: Implications for Hydrophobic Adaptations in Rainy Flight

by Yongheng Shen, Ziheng Xue and Xuecheng Zhang

Insects 2026, 17(4), 393; https://doi.org/10.3390/insects17040393 - 3 Apr 2026

Abstract

Many termite species initiate colonization flights during or shortly after periods of rain, employing two different flight strategies: flying during the day in the rain and flying at night in a dry environment. As noted in previous studies, it appears easier for a [...] Read more.

Many termite species initiate colonization flights during or shortly after periods of rain, employing two different flight strategies: flying during the day in the rain and flying at night in a dry environment. As noted in previous studies, it appears easier for a species to become adapted to a wet environment by changing the contour/shape rather than the composition of the cuticle surface. We utilized differential interference contrast and scanning electron microscopy to observe the micro-nanostructure of the wing cuticles of 54 termite species from 16 families/subfamilies. Twenty-four species of higher termites possessed wings with anti-wetting structures of setae and a micraster array. The majority of lower termite wings had smoother cuticle surfaces. Based on the hierarchical design of termite wings, we conclude that various species are adapted to flying in the rain. Full article

(This article belongs to the Special Issue Insect Wings: Structure, Function, Development, Evolution, and Diversity)

► Show Figures

Figure 1

Journal Description

Insects

Latest Articles

Journal Menu

Journal Browser

Highly Accessed Articles

Latest Books

E-Mail Alert

News

Topics

Conferences

Special Issues

Topical Collections

Further Information

Guidelines

MDPI Initiatives

Follow MDPI