Insects

11 pages, 21934 KiB

Open AccessArticle

Morphology of External Genitalia in the Genus Acanthoponera Mayr, with Redescription of A. mucronata (Roger) Male (Hymenoptera: Formicidae: Ectatomminae)

by Stefano Cantone and Andrea Di Giulio

Insects 2025, 16(4), 436; https://doi.org/10.3390/insects16040436 - 21 Apr 2025

Viewed by 229

Abstract

In this study, using scanning electron microscope (SEM) and optical microscopy, we give a detailed description of the Acanthoponera mucronata male, supplementing the former male-based genus diagnoses. In particular, we described for the first time the following characters: the morphology of the external [...] Read more.

In this study, using scanning electron microscope (SEM) and optical microscopy, we give a detailed description of the Acanthoponera mucronata male, supplementing the former male-based genus diagnoses. In particular, we described for the first time the following characters: the morphology of the external genitalia, the peculiar antennal cleaning and the absence of the metapleural gland orifice. In addition, we show the pretarsal claws and the ventral excavation in the gaster that represent diagnostic male features of all Acanthoponera species, never imaged before. The use of modern taxonomic standards is particularly important in order to make these data available to future comparative analyses. Full article

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

► Show Figures

Figure 1

14 pages, 1706 KiB

Open AccessArticle

Diflubenzuron Did Not Affect the Abilities of the Backswimmer Buenoa tarsalis to Survive and Prey Upon Larvae of Aedes aegypti

by Sabrina H. C. Araujo, Luis G. Salinas Jimenez, Maria J. M. Corrêa, Viviana L. Bohorquez Zapata, Monalisa S. S. Oliveira, Joshua S. Fernandes, Jônatas M. Gomes, Raimundo W. S. Aguiar, Gil R. Santos, Wilson R. Valbon and Eugênio E. Oliveira

Insects 2025, 16(4), 435; https://doi.org/10.3390/insects16040435 - 21 Apr 2025

Viewed by 212

Abstract

The management of mosquitoes that transmit human diseases such as Zika, dengue fever, and chikungunya relies mainly on the abatement of immature stages by larvicidal insecticides [...] Full article

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

► Show Figures

Figure 1

10 pages, 2069 KiB

Open AccessArticle

Bacillus velezensis as a Novel Species for Mosquito Control: Impacts of Exposure on Key Life History Traits of Culex quinquefasciatus

by Abdullah A. Alomar

Insects 2025, 16(4), 434; https://doi.org/10.3390/insects16040434 - 20 Apr 2025

Viewed by 119

Abstract

Bacillus velezensis is a promising mosquito vector biocontrol agent due to its potent larvicidal properties. This study investigated the lethal and sublethal effects of exposure to crude toxin of B. velezensis strain WHk23 on Culex quinquefasciatus. Toxicity bioassays showed a median lethal [...] Read more.

Bacillus velezensis is a promising mosquito vector biocontrol agent due to its potent larvicidal properties. This study investigated the lethal and sublethal effects of exposure to crude toxin of B. velezensis strain WHk23 on Culex quinquefasciatus. Toxicity bioassays showed a median lethal concentration of 28.30 µg/mL for third instar larvae. In addition to direct larval mortality, sublethal exposures resulted in concentration-dependent decreases in survival, fecundity, and fertility. Exposure to different concentrations was found to accelerate larval development, resulting in larger females, yet those females exhibited lower lifespan and diminished reproductive success. These results suggest that exposure to B. velezensis not only reduces mosquito populations but also has lasting effects on important life history parameters, ultimately lowering vectorial capacity and disease transmission risk. This study provides valuable insights into the lethal and sublethal consequences of B. velezensis exposure. Given its potent larvicidal properties, B. velezensis represents a promising biocontrol agent for mosquito vectors. Full article

(This article belongs to the Special Issue Control and Surveillance of Mosquitoes to Reduce the Spread of Mosquito-Borne Disease)

► Show Figures

Figure 1

19 pages, 4412 KiB

Open AccessArticle

Abundance, Diversity and Distribution of Mosquito Species and Molecular Detection of Its Associated Hepatitis C Virus in Sharkia Governorate, Egypt

by Tharwat A. Selim, Sanad H. Ragab, Saber A. Riad, Randa I. Eltaly, Shaimaa H. Mohammed, Somia Eissa Sharawi, Naser Ahmed Alkenani, Ruoa Saleh Almahallawi, Hayat S. Al-Rashidi and Mohamed A. M. El-Tabakh

Insects 2025, 16(4), 433; https://doi.org/10.3390/insects16040433 - 19 Apr 2025

Viewed by 131

Abstract

The presence of mosquitoes in a certain area is sufficient evidence of the transmission of diseases, in addition to the inconvenience and harassment they cause to the population. In order for mosquito control to be successful, there must be sufficient reports and information [...] Read more.

The presence of mosquitoes in a certain area is sufficient evidence of the transmission of diseases, in addition to the inconvenience and harassment they cause to the population. In order for mosquito control to be successful, there must be sufficient reports and information about the extent of the distribution and spread of the mosquito in this area. This study was conducted seasonally to calculate the distribution and abundance of mosquitoes and to initially detect hepatitis C virus in the most abundant species collected in some localities: Kafr Saqr (Hanot, El-Kodah, Abo Shokok, El-Hagarsa); Abo Kebeer (Manshat Radwan, Bane Aiat, Al-Rahmania, Horbat); Diarb Negm (Safor, El-Asaied, Karmot Sahbara, Saft Zreka); and El-Zakazik (Om El-Zein, Bany Amer, Al-Zankalon, Shanbrt El-Mimona) along Sharkia Governorate. According to the results, 12 mosquito species belonging to two genera were recorded in four stations (16 sites). The species Culex pipiens was found to be the most abundant across the majority of locations. It is reaching its peak in Al-Zankalon with a maximum count of 139 ± 7.61 individuals. C. antennatus exhibited a significant level of abundance (p < 0.001), especially in Al-Rahmania (82.5 ± 4.3). Species such as C. perexiguus and An. pharoensis were found in moderate-to-low numbers. The prevailing species is C. pipiens in all locations and seasons, especially during the summer. Other species like C. antennatus and An. pharoensis are also important, although their significance is somewhat less pronounced. Clusters of sites with similar features indicate that specific locations or species exhibit consistent patterns of activity or abundance throughout several seasons. These clusters represent groups of locations that share similar characteristics, as determined by the principal components. The findings of detecting hepatitis C virus in C. pipiens (the most abundant species) collected samples showed negative results for the presence of HCV during the summer season in Sharkia Governorate. Full article

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

► Show Figures

Figure 1

20 pages, 19308 KiB

Open AccessArticle

The Genus Psenulus Kohl, 1897 (Hymenoptera: Crabronidae) in China, with Two New Species and Two New Country Records

by Huifen Jiang, Qiang Li and Li Ma

Insects 2025, 16(4), 432; https://doi.org/10.3390/insects16040432 - 19 Apr 2025

Viewed by 145

Abstract

The genus Psenulus from China is reviewed and two new species are described: Psenulus carinitibialis Jiang & Ma and Psenulus clypeoconvexus Jiang & Ma; two species are newly recorded from China: Psenulus bicinctus Turner, 1912 and Psenulus orinus van Lith, 1973. Additionally, the [...] Read more.

The genus Psenulus from China is reviewed and two new species are described: Psenulus carinitibialis Jiang & Ma and Psenulus clypeoconvexus Jiang & Ma; two species are newly recorded from China: Psenulus bicinctus Turner, 1912 and Psenulus orinus van Lith, 1973. Additionally, the intraspecific morphological variations are clarified and discussed. An identification key to the Chinese species is provided. Full article

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

► Show Figures

Figure 1

15 pages, 1237 KiB

Open AccessArticle

β-1,3-Glucan Recognition Protein Can Inhibit the Proliferation of Bombyx mori Cytoplasmic Polyhedrosis Virus

by Yinong Zhang, Jiming Yan, Yukai Xie, Xiong Wang, Feifei Ren, Haixu Bian and Jingchen Sun

Insects 2025, 16(4), 431; https://doi.org/10.3390/insects16040431 - 19 Apr 2025

Viewed by 233

Abstract

Insects detect pathogens through their germ-line encoded pattern recognition receptors (PRRs). Among these, β-1,3-glucan recognition protein (βGRP) is a crucial PRR that specifically identifies pathogenic microorganisms and triggers innate immune signaling cascades. However, it remains unclear whether βGRP can detect viruses and protect [...] Read more.

Insects detect pathogens through their germ-line encoded pattern recognition receptors (PRRs). Among these, β-1,3-glucan recognition protein (βGRP) is a crucial PRR that specifically identifies pathogenic microorganisms and triggers innate immune signaling cascades. However, it remains unclear whether βGRP can detect viruses and protect the host from viral threats. In this study, using high-throughput sequencing technology, we observed a significant suppression of βGRP-3 in Bombyx mori during infection with the Bombyx mori cytoplasmic polyhedrosis virus (BmCPV). Moreover, overexpression of βGRP-3 in BmN cell lines resulted in a reduction of BmCPV proliferation, whereas knockdown of βGRP-3 in BmN cells promoted BmCPV proliferation. These findings suggest that the βGRP family functions not only as anti-bacterial, antifungal, and anti-yeast PRRs but also as protectors against various harmful viruses in insects. Full article

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

► Show Figures

Figure 1

16 pages, 3140 KiB

Open AccessArticle

Differences in Morphology of Rural vs. Urban Individuals of the Flightless Ground Beetle, Carabus convexus

by Tibor Magura, Roland Horváth, Szabolcs Mizser, Mária Tóth and Gábor L. Lövei

Insects 2025, 16(4), 430; https://doi.org/10.3390/insects16040430 - 19 Apr 2025

Viewed by 316

Abstract

Urbanization causes significant environmental and structural changes in habitats, one of them being increased fragmentation. Traits associated with increased locomotory capacity may be advantageous in such situations, as individuals with those traits may expand their home range or have a chance to escape [...] Read more.

Urbanization causes significant environmental and structural changes in habitats, one of them being increased fragmentation. Traits associated with increased locomotory capacity may be advantageous in such situations, as individuals with those traits may expand their home range or have a chance to escape the patch where conditions threaten their survival. Individuals of the forest specialist, flightless ground beetle Carabus convexus in urban habitats may respond to urbanization by increasing their locomotory capacity (increased muscle mass) with respect to their conspecifics in rural habitats. In order to test this hypothesis, morphological traits standardized for body size were assessed using linear mixed-effects models. Pronotum volume (as a proxy for muscle mass) showed no significant difference between urban and rural individuals. The size of the tibia and femur of the front, middle, and hind legs (a proxy for leg muscle mass) significantly differed between sexes, with males having significantly larger tibiae and femora than females. Furthermore, urban males had significantly larger hind tibiae than rural conspecifics. Sex-specific differences in tibia and femur size is expected because males usually have higher locomotory activity than females. Larger tibiae of urban males can be advantageous to extend their home range, ensuring that males find mating partners even in low-density urban populations. Full article

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

► Show Figures

Figure 1

16 pages, 1246 KiB

Open AccessArticle

Suitability of Artificial Diets Containing Various Types of Pollen Grains to Helicoverpa armigera (Hübner, 1808): Nutritional Performance and Digestive Enzyme Response

by Fatemeh Kefayat, Seyed Ali Hemmati, Arash Rasekh, Fatemeh Nasernakhaei and Lukasz L. Stelinski

Insects 2025, 16(4), 429; https://doi.org/10.3390/insects16040429 - 19 Apr 2025

Viewed by 241

Abstract

The development of an effective artificial diet is essential for the mass rearing of insects used in pest management programs, including augmentative biological control, insecticide resistance monitoring, and sterile insect release. This study evaluated the consumption, utilization, and enzymatic responses of the polyphagous [...] Read more.

The development of an effective artificial diet is essential for the mass rearing of insects used in pest management programs, including augmentative biological control, insecticide resistance monitoring, and sterile insect release. This study evaluated the consumption, utilization, and enzymatic responses of the polyphagous pest Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae) when reared on meridic diets supplemented with different pollen grains. The control diet followed a well-established meridic formulation, while the eight experimental diets incorporated pollen from the honey bee, rapeseed, maize, sunflower, hollyhock, glossy shower, saffron, and date palm. The findings indicate that pollen supplementation enhances the quality of artificial diets for H. armigera. Larvae fed on the date palm pollen-supplemented diet exhibited significantly higher weight gain, efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), and relative growth rate (RGR) compared to those fed on the control diet. The highest relative consumption rate (RCR) was observed in larvae fed on the sunflower pollen-supplemented diet. Additionally, pollen-supplemented diets influenced the amylolytic and proteolytic enzyme activities of H. armigera larvae in a diet-dependent manner. Nutritional analysis of the pollen types revealed significant variations in the sugar, lipid, and protein contents. Cluster analysis further identified the date palm pollen-supplemented diet as the most nutritionally beneficial, suggesting its potential application in the large-scale production of H. armigera. Full article

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

► Show Figures

Graphical abstract

10 pages, 911 KiB

Open AccessArticle

Life Table Parameters and Digestive Enzyme Activity of Araecerus fasciculatus (Coleoptera: Anthribidae) Feeding on Different Stored Products

by Lingyan Jian, Yuping Yang, Songhai Xie, Yibin Lou, Ling Chen, Fanglian Dai, Paraskevi Agrafioti, Yu Cao, Christos G. Athanassiou and Can Li

Insects 2025, 16(4), 428; https://doi.org/10.3390/insects16040428 - 18 Apr 2025

Viewed by 193

Abstract

Araecerus fasciculatus (De Geer, 1775) is an important stored-product pest worldwide. In this study, the development time, survival rate, oviposition, and digestive enzyme (α-amylase, cellulase, pepsin, and lipase) activities of A. fasciculatus fed on five commodities (coffee, jujube, maize, wheat, and [...] Read more.

Araecerus fasciculatus (De Geer, 1775) is an important stored-product pest worldwide. In this study, the development time, survival rate, oviposition, and digestive enzyme (α-amylase, cellulase, pepsin, and lipase) activities of A. fasciculatus fed on five commodities (coffee, jujube, maize, wheat, and kansui) were investigated. Our results showed that the developmental duration of A. fasciculatus from egg to adult was shortest on coffee beans (51.41 days) and longest on kansui (69.65 days). The survival rate of A. fasciculatus adults was lowest on kansui (42.22%) and highest on coffee beans (63.33%). Significant differences in fecundity were also observed, with the greatest number on coffee beans (80.78 eggs/female) and the lowest on kansui (50.43 eggs/female). Araecerus fasciculatus showed the greatest intrinsic rate of natural increase (r_m) on coffee beans (0.141), followed by jujube (0.129), maize (0.117), wheat (0.105), and kansui (0.097). The net productive rate (R₀) showed a similar trend to r_m, with values of 48.42, 42.53, 35.39, 27.53, and 21.47, respectively, on these stored products. Although no significant differences were observed in the lipase activities when A. fasciculatus was fed on different stored products, activities of α-amylase, pepsin, and cellulase were highest on coffee beans and lowest on kansui. The variation in the population development of A. fasciculatus associated with different foods may be related to its digestive enzyme performance. These results indicated that coffee beans were the most suitable host food, while kansui was the least suitable for the development of A. fasciculatus. Full article

(This article belongs to the Special Issue Controlling Insect Pests in Postharvest Agricultural Products Using Non-Chemical Methods)

► Show Figures

Figure 1

23 pages, 902 KiB

Open AccessArticle

Farmers’ Perception of Fall Armyworm (Spodoptera frugiperda) as an Invasive Pest and Its Management

by Waseem Akbar, Sumaira Yousaf, Muhammad Farhan Saeed, Wafa A. H. Alkherb, Asim Abbasi, Nazih Y. Rebouh and Nazia Suleman

Insects 2025, 16(4), 427; https://doi.org/10.3390/insects16040427 - 18 Apr 2025

Viewed by 277

Abstract

This study was carried out with the aim of understanding how farmers perceive and deal with fall armyworm (FAW) infestations in maize crops. Data based on a questionnaire were collected across nine districts of the Punjab province in Pakistan. Findings revealed that about [...] Read more.

This study was carried out with the aim of understanding how farmers perceive and deal with fall armyworm (FAW) infestations in maize crops. Data based on a questionnaire were collected across nine districts of the Punjab province in Pakistan. Findings revealed that about 38% of farmers had medium-sized landholdings and had been cultivating maize crop for the last 11–20 years. Hybrid maize seed was used by 55% of the farmers, and 60% of the maize grown was used as fodder, as well as a cash crop. Surprisingly, only 39% of farmers were able to correctly identify FAW; however, the majority (72%) recognized the larvae as the most damaging stage. Although most of the farmers (71%) grew maize crops during both seasons, only 34% of the farmers recognized autumn as the peak infestation period of FAW. However, despite limited awareness, a high percentage (86%) of farmers managed FAW effectively using various chemical treatments. This study also highlighted the influence of some factors on farmers’ perception of FAW such as: age, farming experience, and maize cultivation practices. Overall, the findings emphasize the need for increased awareness of the basic biology and targeted management strategies for FAW to safeguard maize crops in the region. Full article

(This article belongs to the Special Issue Spodoptera frugiperda: Current Situation and Future Prospects)

► Show Figures

Figure 1

13 pages, 2630 KiB

Open AccessArticle

Rapid and Economic Baculovirus Titer Determination Using a Novel Transgenic Sf9-QE Cell Line

by Hyuk-Jin Moon, Hyun-Jung Kim, Dong-Hyun Lee, Seo-Yeong Mun and Soo-Dong Woo

Insects 2025, 16(4), 426; https://doi.org/10.3390/insects16040426 - 17 Apr 2025

Viewed by 223

Abstract

A baculovirus expression system (BES) for the production of recombinant proteins requires rapid and easy virus titer determination. In this study, a novel direct titration method was developed using a novel Sf9-QE cell line to easily and economically determine virus titers in a [...] Read more.

A baculovirus expression system (BES) for the production of recombinant proteins requires rapid and easy virus titer determination. In this study, a novel direct titration method was developed using a novel Sf9-QE cell line to easily and economically determine virus titers in a short time. This direct titration method can determine virus titers by directly counting the initially infected cells. This method requires the rapid identification of the initial virus-infected cells. The genome of Sf9-QE cells, which fluoresce upon virus infection, was found to contain at least seven copy numbers of the enhanced green fluorescent protein (EGFP) transgene. This result suggests that Sf9-QE cells in the early stages of virus infection can be identified by the high expression of EGFP. It was also shown that for accurate virus titration using the direct titration method, Sf9-QE cells should be used within 3 d of subculturing. Additionally, counting fluorescent cells to establish virus infection should be performed within 15 to 30 h after virus infection for reliable virus titration. The direct titration method using Sf9-QE cells provides a rapid, reliable, and cost-effective alternative for determining baculovirus titers in BES research. Full article

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

► Show Figures

Graphical abstract

12 pages, 755 KiB

Open AccessArticle

Leaffooted Bugs, Leptoglossus phyllopus (Hemiptera: Coreidae), Are Attracted to Volatile Emissions from Herbivore-Damaged Cotton Bolls

by Malek A. Alwedyan, Anjel M. Helms and Michael J. Brewer

Insects 2025, 16(4), 425; https://doi.org/10.3390/insects16040425 - 17 Apr 2025

Viewed by 141

Abstract

The leaffooted bug, Leptoglossus phyllopus (L.) (Hemiptera: Coreidae), probes and feeds on tissues of many plant species, including developing cotton bolls, causing seed damage and abscission. Insecticides are the primary tool for managing leaffooted bugs, but concerns about resistance and environmental harm highlight the [...] Read more.

The leaffooted bug, Leptoglossus phyllopus (L.) (Hemiptera: Coreidae), probes and feeds on tissues of many plant species, including developing cotton bolls, causing seed damage and abscission. Insecticides are the primary tool for managing leaffooted bugs, but concerns about resistance and environmental harm highlight the need for alternative management strategies. One promising approach is using semiochemicals, such as plant- and insect-produced volatile organic compounds (VOCs), to trap or repel pests. Insect herbivores often use plant-produced VOCs to select suitable host plants for feeding and oviposition. Field observations of abundant adult leaffooted bugs on cotton bolls suggest that bugs aggregate at feeding sites. The goal of this study was to characterize VOCs from developing cotton bolls with and without leaffooted bug herbivory and evaluate how these VOCs affect adult bug foraging behavior. A portable dynamic headspace sampling method was used to collect VOCs from developing cotton bolls in the field, and VOC samples were analyzed using gas chromatography–mass spectrometry. Leaffooted bug herbivory induced volatile emissions from cotton bolls, with significant increases in the emissions of six compounds (benzaldehyde, α-pinene, β-pinene, β-myrcene, p-xylene, and (E)-β-caryophyllene). Dual-choice olfactometer assays revealed that adult leaffooted bugs were attracted to VOCs from damaged cotton bolls, as well as being attracted to synthetic benzaldehyde or α-pinene individually. In contrast, leaffooted bugs were repelled by the combination of synthetic benzaldehyde and α-pinene. These findings suggest that VOCs from cotton bolls are attractive to leaffooted bugs and could contribute to the development of attractive lures for integrated pest management. Full article

(This article belongs to the Special Issue Advances in Chemical Ecology of Plant–Insect Interactions)

► Show Figures

Figure 1

17 pages, 3529 KiB

Open AccessArticle

Centrifugation-Based Purification Protocol Optimization Enhances Structural Preservation of Nucleopolyhedrovirus Budded Virion Envelopes

by Yong Pan, Jiming Yan, Yinong Zhang, Jiasheng Lin, Zhiquan Liang and Jingchen Sun

Insects 2025, 16(4), 424; https://doi.org/10.3390/insects16040424 - 17 Apr 2025

Viewed by 198

Abstract

The structural integrity of viral envelopes is a critical determinant of infectivity for enveloped viruses, directly influencing vector stability, functional accuracy of surface-displayed epitopes, and preservation of native conformational states required for membrane protein studies. However, conventional purification methods often disrupt envelope integrity [...] Read more.

The structural integrity of viral envelopes is a critical determinant of infectivity for enveloped viruses, directly influencing vector stability, functional accuracy of surface-displayed epitopes, and preservation of native conformational states required for membrane protein studies. However, conventional purification methods often disrupt envelope integrity and cause envelope proteins to lose their activity. Here, we systematically compared discontinuous, continuous, and optimized continuous sucrose density gradient centrifugation protocols for purifying Autographa californica multiple nucleopolyhedrovirus (AcMNPV). Through cryo-EM, we demonstrated that our optimized continuous sucrose gradient protocol significantly increased the proportion of AcMNPV budded virions with intact envelopes from 36% to 81%, while preserving the metastable prefusion conformation of the fusion protein GP64. This advancement should prove useful for structural studies of viral envelope proteins and may enhance applications in gene therapy and vaccine development utilizing enveloped viruses. Full article

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

► Show Figures

Figure 1

21 pages, 2734 KiB

Open AccessArticle

Assessing the Influence of Stimulatory Feeding of Bee Colonies on Mineral Composition and Antioxidant Activity of Bee Venom

by Adrian Dan Rășinar, Isidora Radulov, Adina Berbecea, Doris Floares (Oarga), Nicoleta Vicar, Eliza Simiz, Monica Dragomirescu and Silvia Pătruică

Insects 2025, 16(4), 423; https://doi.org/10.3390/insects16040423 - 17 Apr 2025

Viewed by 195

Abstract

Bee venom is a complex natural beekeeping product, traditionally used in apitherapy, with a wide spectrum of pharmacological properties. Research on the mineral content of bee venom is limited and challenging to compare across studies due to the varying regions where they are [...] Read more.

Bee venom is a complex natural beekeeping product, traditionally used in apitherapy, with a wide spectrum of pharmacological properties. Research on the mineral content of bee venom is limited and challenging to compare across studies due to the varying regions where they are conducted. Our study aimed to assess the mineral content of bee venom and how supplementary feeding of bee colonies with probiotic products, essential oils, as well as rapeseed and acacia nectar and pollen, affects the mineral content and antioxidant activity of the venom. The parameters analyzed included moisture, pH, dry matter, ash, impurities, and levels of macro and micro elements and antioxidant activity. The moisture content of the samples was 10–22%, and pH ranged between 5.84 to 6.41. The macro element content of the venom showed that potassium was the most abundant macro element, followed by calcium, magnesium, and phosphorus. Pb was identified in samples collected indicating lead pollution in the area where the hives were located in the case of the three harvests. In all samples, the highest DPPH radical scavenging activity was observed at a concentration of 2.00 mg/mL, with sample V6 showing the maximum value of 87.05%. Full article

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

► Show Figures

Graphical abstract

17 pages, 4500 KiB

Open AccessArticle

The Frequency and Spread of a GABA-Gated Chloride Channel Target-Site Mutation and Its Impact on the Efficacy of Ethiprole Against Neotropical Brown Stink Bug, Euschistus heros (Hemiptera: Pentatomidae)

by Ana C. P. Cuenca, Bettina Lueke, Renato Vicentini and Ralf Nauen

Insects 2025, 16(4), 422; https://doi.org/10.3390/insects16040422 - 17 Apr 2025

Viewed by 185

Abstract

The Neotropical brown stink bug (NBSB), Euschistus heros, is the most prevalent sucking soybean pest in Brazil, and control of it largely relies on the application of synthetic insecticides such as ethiprole, a phenylpyrazole insecticide targeting GABA-gated chloride channels encoded by the [...] Read more.

The Neotropical brown stink bug (NBSB), Euschistus heros, is the most prevalent sucking soybean pest in Brazil, and control of it largely relies on the application of synthetic insecticides such as ethiprole, a phenylpyrazole insecticide targeting GABA-gated chloride channels encoded by the Rdl (resistant to dieldrin) gene. This study monitored 41 NBSB populations collected between 2021 and 2024 and revealed, for the first time, the presence of a mutation, A301S, in NBSB RDL receptors commonly known to confer target-site resistance to channel blockers such as phenylpyrazoles. Laboratory contact bioassays with ethiprole at 150 g a.i./ha (ethiprole label dose) revealed that most populations were quite susceptible, despite rather high resistance allele frequencies in some populations. Genotyping results confirmed that susceptible and A301S heterozygous genotypes largely dominate in frequency compared to homozygous resistant individuals, which exhibited high survivorship (84%) when exposed to discriminating rates of ethiprole in laboratory bioassays, while susceptible and heterozygote individuals showed lower survival rates (13% and 34%, respectively), suggesting an incompletely recessive trait conferring ethiprole resistance. Furthermore, we developed a TaqMan assay for molecular genotyping to monitor the spread of resistance allele frequency and to inform resistance management strategies for sustainable NBSB control using highly effective phenylpyrazole insecticides such as ethiprole. Full article

(This article belongs to the Special Issue Chemical Toxicology and Insecticide Resistance on Insect Pests)

► Show Figures

Graphical abstract

27 pages, 6986 KiB

Open AccessArticle

Genome-Wide Identification and Expression Profiling of Glycosidases, Lipases, and Proteases from Invasive Asian Palm Weevil, Rhynchophorus ferrugineus

by Nazmi Harith-Fadzilah, Mohammad Nihad, Mohammed Ali AlSaleh, Abdulqader Yaslam Bazeyad, Subash-Babu Pandurangan, Kashif Munawar, Arya Vidyawan, Hattan A. Alharbi, Jernej Jakše, Arnab Pain and Binu Antony

Insects 2025, 16(4), 421; https://doi.org/10.3390/insects16040421 - 17 Apr 2025

Viewed by 303

Abstract

The red palm weevil, Rhynchophorus ferrugineus, is a destructive, invasive pest to a diverse range of palm plantations globally. Commonly used broad-range chemical insecticides for insect control pose high risks to non-target organisms, humans, and the environment. A bio-rational approach of screening [...] Read more.

The red palm weevil, Rhynchophorus ferrugineus, is a destructive, invasive pest to a diverse range of palm plantations globally. Commonly used broad-range chemical insecticides for insect control pose high risks to non-target organisms, humans, and the environment. A bio-rational approach of screening natural small-molecule inhibitors that specifically target R. ferrugineus proteins critical to its life processes can pave the way for developing novel bioinsecticides. Digestive enzymes (DEs), which impair feeding on plants (herbivory), are promising targets. We generated de novo transcriptomes, annotated DE-related genes from the R. ferrugineus gut and abdomen, manually annotated the DE gene family from the recently available genome and our transcriptome data, and reported 34 glycosidases, 85 lipases, and 201 proteases. We identified several tandem duplicates and allelic variants from the lipase and protease families, notably, 10 RferLip and 21 RferPro alleles, which emerged primarily through indels and single-site substitution. These alleles may confer enhanced digestive lipolysis and proteolysis. Phylogenetic analyses identified and classified different subfamilies of DEs and revealed close evolutionary relationships with other coleopterans. We assessed select candidate DEs’ activity and the potential for inhibition in silico to better understand the herbivory arsenal. In silico analysis revealed that the selected enzymes exhibited similar ligand-binding affinity to their corresponding substrate, except for protease aminopeptidase N, RferPro40, which exhibited poorer affinity to the inhibitor bestatin. Overall, our study serves as a foundation for further functional analysis and offers a novel target for the development of a novel bio-rational insecticide for R. ferrugineus. Full article

(This article belongs to the Special Issue Natural Metabolites as Biocontrol Agents of Insect Pests)

► Show Figures

Figure 1

11 pages, 2171 KiB

Open AccessArticle

Comparative Mitogenomic Analyses of Psectrocladius (Diptera: Chironomidae)

by Xue-Yao Chen, Xiu-Ru Xiao, Yan Zhang, Zhi-Chao Zhang, Dong-Sheng Zhang, Zheng Liu and Xiao-Long Lin

Insects 2025, 16(4), 420; https://doi.org/10.3390/insects16040420 - 16 Apr 2025

Viewed by 190

Abstract

Psectrocladius, a genus within the species-rich subfamily Orthocladiinae (Diptera: Chironomidae), remains poorly resolved in molecular phylogenetics due to limited available molecular data. Here, we sequenced and analyzed the complete mitogenomes of five Psectrocladius species, using two Rheocricotopus species as outgroups. Our results [...] Read more.

Psectrocladius, a genus within the species-rich subfamily Orthocladiinae (Diptera: Chironomidae), remains poorly resolved in molecular phylogenetics due to limited available molecular data. Here, we sequenced and analyzed the complete mitogenomes of five Psectrocladius species, using two Rheocricotopus species as outgroups. Our results reveal that the mitogenomes of Psectrocladius are structurally conserved and retain a presumed ancestral gene order. The nucleotide composition of these newly generated mitogenomes exhibits a pronounced A + T bias, which is characteristic of typical insect mitogenomes. The substitution rates, estimated using Ka/Ks ratios, indicate that all protein-coding genes are under purifying selection. The strongest purifying selection pressure was observed in the CO1 gene, while the weakest was in the ND5 gene. Both the maximum likelihood and Bayesian inference trees consistently show the following topology: ((((P. schlienzi + P. bisetus) + P. barbimanus) + P. oligosetus) + P. aquatronus). This study provides key insights into chironomid mitogenomes and their gene properties, offering valuable reference data for future research. Full article

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

► Show Figures

Figure 1

13 pages, 3079 KiB

Open AccessArticle

Oviposition Competition Between Zeugodacus cucurbitae and Bactrocera dorsalis Adults in Five Hosts

by Hongai Su, Jin Zhao, Haikuo Yu, Saleem Jaffar, Zhenyu Hao, Guangwen Liang, Ling Zeng and Yongyue Lu

Insects 2025, 16(4), 419; https://doi.org/10.3390/insects16040419 - 15 Apr 2025

Viewed by 177

Abstract

The Zeugodacus cucurbitae and Bactrocera dorsalis are economically significant pests that share similar habitats and host plants, leading to intense interspecific competition. To elucidate their competitive interactions, this study investigated the oviposition competition behavior of mixed laboratory populations on five common host plants: [...] Read more.

The Zeugodacus cucurbitae and Bactrocera dorsalis are economically significant pests that share similar habitats and host plants, leading to intense interspecific competition. To elucidate their competitive interactions, this study investigated the oviposition competition behavior of mixed laboratory populations on five common host plants: pumpkin (Cucurbita moschata), cucumber (Cucumis sativus), winter melon (Benincasa hispida), bitter melon (Momordica charantia) and guava (Psidium guajava). The results exhibited that among the five hosts tested, B. dorsalis exhibited a significant competitive advantage in oviposition on pumpkin and bitter melon, with its fecundity greater than that of Z. cucurbitae across all ratios. Conversely, Z. cucurbitae showed a clear preference for cucumber. Except at the extreme ratio of 16:4, where B. dorsalis laid slightly more eggs than that of Z. cucurbitae, Z. cucurbitae laid more eggs at all ratios. The results can provide a reference for further investigation on the oviposition selectivity and interspecific competition between the adults of Z. cucurbitae and B. dorsalis. Full article

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

► Show Figures

Figure 1

12 pages, 1061 KiB

Open AccessArticle

Wolbachia Screening in Aedes aegypti and Culex pipiens Mosquitoes from Madeira Island, Portugal

by Rita Fernandes, Tiago Melo, Líbia Zé-Zé, Inês C. Freitas, Manuel Silva, Eva Dias, Nuno C. Santos, Bruna R. Gouveia, Gonçalo Seixas and Hugo Costa Osório

Insects 2025, 16(4), 418; https://doi.org/10.3390/insects16040418 - 15 Apr 2025

Viewed by 699

Abstract

Mosquito-borne diseases such as dengue and West Nile virus pose serious public health risks. On Madeira Island, the presence of the mosquito species Aedes aegypti (Linnaeus, 1762) and Culex pipiens (Linnaeus, 1758) raises concerns about local transmission. In this study, we tested 100 [...] Read more.

Mosquito-borne diseases such as dengue and West Nile virus pose serious public health risks. On Madeira Island, the presence of the mosquito species Aedes aegypti (Linnaeus, 1762) and Culex pipiens (Linnaeus, 1758) raises concerns about local transmission. In this study, we tested 100 Ae. aegypti and 40 Cx. pipiens mosquitoes collected exclusively in the municipality of Funchal, Madeira Island, to assess the presence and diversity of Wolbachia, a naturally occurring bacterium known to reduce mosquitos’ ability to transmit viruses. Molecular identification confirmed that all Cx. pipiens specimens belonged to the molestus biotype, with three individuals identified as hybrids between molestus and pipiens biotypes. This is the first evidence of such hybrids in Madeira. Wolbachia was not detected in any of the Ae. aegypti samples. In contrast, all Cx. pipiens mosquitoes were positive, showing a 100% prevalence. Genetic characterization placed these infections within the wPip clade, supergroup B, sequence type 9. These findings provide key baseline data to inform future mosquito control strategies on the island. As Ae. aegypti showed no natural Wolbachia infection, introducing Wolbachia-infected mosquitoes may be necessary to implement such biocontrol approaches in Madeira. Full article

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

► Show Figures

Figure 1

10 pages, 1540 KiB

Open AccessArticle

Pre-Crop Chemical Control Has No Effects on Corn Leaf Aphid, Rhopalosiphum maidis (Fitch) (Hemiptera: Aphididae) Endosymbiotic Bacterial Diversity Along an Industrial Maize Management

by Artúr Botond Csorba, Kálmán Szanyi, Szabolcs Szanyi, Gábor Tarcali, Adalbert Balog and Antal Nagy

Insects 2025, 16(4), 417; https://doi.org/10.3390/insects16040417 - 15 Apr 2025

Viewed by 292

Abstract

During this research, the corn leaf aphids endosymbiotic bacterial diversity was tested in the same crop systems (monoculture industrial maize as grain for livestock) and the same soil type (Chernozem) when pre-crop pesticide management was used. Bacterial symbionts were analyzed using Illumina systems, [...] Read more.

During this research, the corn leaf aphids endosymbiotic bacterial diversity was tested in the same crop systems (monoculture industrial maize as grain for livestock) and the same soil type (Chernozem) when pre-crop pesticide management was used. Bacterial symbionts were analyzed using Illumina systems, and the Silva 16S NR99 V138.2 database was used to assign bacterial taxa on genus and species levels. The presence of the obligate endosymbiont B. aphidicola has been clearly detected in all cases, and in all samples but its abundance varied between samples inside crops, but not between crops and generations. The facultative symbionts S. symbiotica and Wolbachia spp. frequency varied between generations, and increased at generation II; however, differences were not significant. We concluded that the pre-crop pesticide application has no effect on corn leaf aphids bacterial symbionts, so the indirect pesticide application on aphids adaptation is low or nonexistent. Full article

(This article belongs to the Special Issue Biology and Molecular Mechanisms of Plant-Aphid Interactions)

► Show Figures

Figure 1

14 pages, 912 KiB

Open AccessArticle

More than Just Host Plant Preferences for the Two Main Vectors of Xylella fastidiosa in Europe: Two Insect Species and Two Different Behaviors

by Saúl Bernat-Ponce, Rosalía García-García, Cristina M. Aure, Lorena Nieves, Juan Pedro Bouvet, Francisco J. Beitia and César Monzó

Insects 2025, 16(4), 416; https://doi.org/10.3390/insects16040416 - 15 Apr 2025

Viewed by 383

Abstract

Xylella fastidiosa is a vector-borne bacterium causing significant economic losses in global agricultural industries. Management strategies focus primarily on controlling vector populations. The diversity of vector species, their polyphagy, and the wide range of host plants supporting bacterial development make X. fastidiosa pathosystems [...] Read more.

Xylella fastidiosa is a vector-borne bacterium causing significant economic losses in global agricultural industries. Management strategies focus primarily on controlling vector populations. The diversity of vector species, their polyphagy, and the wide range of host plants supporting bacterial development make X. fastidiosa pathosystems particularly challenging to manage. Understanding vector and host plant relationships is key to developing effective strategies. This study examined the oviposition strategies, host preferences, and nymphal development of Europe’s main X. fastidiosa vectors, Philaenus spumarius and Neophilaenus campestris, under semi-field conditions (screenhouse). The two species exhibited distinct behaviors. Neophilaenus campestris primarily laid eggs on its preferential host, the grass Festuca arundinacea, while P. spumarius preferred dry soil substrates, irrespective of the host plant species. The presence of multiple hosts reduced the oviposition rates of P. spumarius compared with single-host scenarios. The nymphs of P. spumarius quickly identified and settled on preferential hosts, while the N. campestris nymphs initially moved randomly but later congregated on their preferred host. Despite their polyphagy, nymph survival was limited to preferential hosts. These findings highlight opportunities for habitat management strategies, such as enhancing plant diversity and eliminating overwintering egg sites, to mitigate vector populations and limit the spread of X. fastidiosa. Full article

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

► Show Figures

Figure 1

29 pages, 2547 KiB

Open AccessArticle

Mechanisms Maintaining Mitochondrial DNA Polymorphisms: The Role of Mito-Nuclear Interactions, Sex-Specific Selection, and Genotype-by-Environment Interactions in Drosophila subobscura

by Pavle Erić, Marija Savić Veselinović, Aleksandra Patenković, Marija Tanasković, Bojan Kenig, Katarina Erić, Boris Inđić, Stefan Stanovčić and Mihailo Jelić

Insects 2025, 16(4), 415; https://doi.org/10.3390/insects16040415 - 15 Apr 2025

Viewed by 365

Abstract

Experimental mito-nuclear introgression lines (MNILs) were established by backcrossing isofemale lines of D. subobscura originating from the same populations. MNILs were subjected to a series of life-history experiments designed to test the fitness of the bearers of different combinations of two main mtDNA [...] Read more.

Experimental mito-nuclear introgression lines (MNILs) were established by backcrossing isofemale lines of D. subobscura originating from the same populations. MNILs were subjected to a series of life-history experiments designed to test the fitness of the bearers of different combinations of two main mtDNA haplotypes on their own nuclear background, as well as on the background of the opposite haplotype. By having 11 replicas of the four mito-nuclear combinations, we could test not only the adaptive significance of the differences between the two main haplotypes but also the influence of additional variation present within each of the 11 combinations on fitness. Testing the fitness of individuals of both sexes enabled us to examine if sex-specific selection has a role in maintaining the frequencies of the two mtDNA haplotypes in nature. Conducting the fitness assays on two different temperatures enabled us to test whether different temperatures favor specific mtDNA haplotypes or mito-nuclear genotypes and consequently promote stable sympatric mtDNA variation. The results show weak signature of genotype-by-environment interactions, and no sex-specific selection regarding differences between the two main haplotypes. However, individual models across different life-history components showed these two mechanisms at play in promoting mtDNA variability present in specific mito-nuclear crosses. Our models show that mito-nuclear interactions are, in fact, more important as units of selection. Full article

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

► Show Figures

Figure 1

18 pages, 1764 KiB

Open AccessReview

Food as Medicine: A Review of Plant Secondary Metabolites from Pollen, Nectar, and Resin with Health Benefits for Bees

by Bandele Morrison, Laura R. Newburn and Gordon Fitch

Insects 2025, 16(4), 414; https://doi.org/10.3390/insects16040414 - 15 Apr 2025

Viewed by 335

Abstract

Bees rely on pollen and nectar for nutrition, but floral products provide more than just macronutrients; many also contain an array of plant secondary metabolites (PSMs). These compounds are generally thought to serve primarily defensive purposes but also appear to promote longevity and [...] Read more.

Bees rely on pollen and nectar for nutrition, but floral products provide more than just macronutrients; many also contain an array of plant secondary metabolites (PSMs). These compounds are generally thought to serve primarily defensive purposes but also appear to promote longevity and immune function, protect against disease agents, and detoxify toxicants. This review presents a comprehensive overview of PSMs, as well as some fatty acids, with documented health benefits for eusocial bees at ecologically relevant exposure levels and the plant species whose floral products and/or resin are known to contain them. We find medicinal metabolites to be widespread but unevenly distributed across the plant phylogeny, with a few families containing a majority of the species known to produce PSMs with documented health benefits. We discuss the current state of knowledge and identify gaps in our understanding. The existing literature on the health benefits of metabolites, and particularly PSMs, to bees is spread across multiple fields; our hope is that this review will bring these fields closer together and encourage further investigation of the role of metabolites in promoting bee health in ecological contexts. Full article

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

► Show Figures

Figure 1

14 pages, 4447 KiB

Open AccessArticle

A New Species Nyctegretis seminigra sp. nov. (Pyralidae, Phycitinae) Revealed by Congruent Morphological and Mitogenomic Evidence

by Linlin Yang, Yuxian Zhou and Yingdang Ren

Insects 2025, 16(4), 413; https://doi.org/10.3390/insects16040413 - 14 Apr 2025

Viewed by 207

Abstract

The genus Nyctegretis was established by Zeller [...] Full article

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

► Show Figures

Figure 1

28 pages, 15291 KiB

Open AccessArticle

Impact of Ectropis grisescens Warren (Lepidoptera: Geometridae) Infestation on the Tea Plant Rhizosphere Microbiome and Its Potential for Enhanced Biocontrol and Plant Health Management

by He Liu, Wei Chen, Xiaohong Fang, Dongliang Li, Yulin Xiong, Wei Xie, Qiulian Chen, Yingying You, Chenchen Lin, Zhong Wang, Jizhou Wang, Danni Chen, Yanyan Li, Pumo Cai, Chuanpeng Nie and Yongcong Hong

Insects 2025, 16(4), 412; https://doi.org/10.3390/insects16040412 - 14 Apr 2025

Viewed by 434

Abstract

The root-associated microbiome significantly influences plant health and pest resistance, yet the temporal dynamics of its compositional and functional change in response to Ectropis grisescens Warren (Lepidoptera: Geometridae) infestation remain largely unexplored. The study took samples of leaves, roots, and rhizosphere soil at [...] Read more.

The root-associated microbiome significantly influences plant health and pest resistance, yet the temporal dynamics of its compositional and functional change in response to Ectropis grisescens Warren (Lepidoptera: Geometridae) infestation remain largely unexplored. The study took samples of leaves, roots, and rhizosphere soil at different times after the plants were attacked by E. grisescens. These samples were analyzed using transcriptomic and high-throughput sequencing of 16S rRNA techniques. The goal was to understand how the plant’s defense mechanisms and the microbial community around the roots changed after the attack. Additionally, bacterial feedback assays were conducted to evaluate the effects of selected microbial strains on plant growth and pest defense responses. By conducting 16S rRNA sequencing on the collected soil samples, we found significant shifts in bacterial communities by the seventh day, suggesting a lag in community adaptation. Transcriptomic analysis revealed that E. grisescens attack induced reprogramming of the tea root transcriptome, upregulating genes related to defensive pathways such as phenylpropanoid and flavonoid biosynthesis. Metagenomic data indicated functional changes in the rhizosphere microbiome, with enrichment in genes linked to metabolic pathways and nitrogen cycling. Network analysis showed a reorganization of core microbial members, favoring nitrogen-fixing bacteria like Burkholderia species. Bacterial feedback assays confirmed that selected strains, notably Burkholderia cepacia strain ABC4 (T1) and a nine-strain consortium (T5), enhanced plant growth and defense responses, including elevated levels of flavonoids, polyphenols, caffeine, jasmonic acid, and increased peroxidase (POD) and superoxide dismutase (SOD) activities. This study emphasizes the potential of utilizing root-associated microbial communities for sustainable pest management in tea cultivation, thereby enhancing resilience in tea crops while maintaining ecosystem balance. Full article

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

► Show Figures

Figure 1

18 pages, 23535 KiB

Open AccessReview

The Lichenophanes Lesne, 1899 of the Palaearctic and Oriental Regions (Coleoptera, Bostrichidae)

by Jerzy Borowski, Hervé Brustel, Artur Rutkiewicz, Tomasz Oszako and Andrzej Lasoń

Insects 2025, 16(4), 411; https://doi.org/10.3390/insects16040411 - 14 Apr 2025

Viewed by 334

Abstract

This paper includes a review of the Palaearctic and Oriental species of the genus Lichenophanes Lesne, 1899. It contains a description of the new species, Lichenophanes juxtaorientalis n. sp., which occurs in Cyprus and Crete. A new subspecies, Lichenophanes varius turanicus n. subsp.—occurring [...] Read more.

This paper includes a review of the Palaearctic and Oriental species of the genus Lichenophanes Lesne, 1899. It contains a description of the new species, Lichenophanes juxtaorientalis n. sp., which occurs in Cyprus and Crete. A new subspecies, Lichenophanes varius turanicus n. subsp.—occurring in Crete, Cyprus, and the Middle East—was separated from the species Lichenophanes varius (Illiger) and described. Moreover, this paper characterizes L. carinatus (Lewis) n. stat., which had been treated as a synonym of L. carinipennis (Lewis). Two maps present the geographic distribution of particular species, and the final part of this paper contains keys to identify them. Full article

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

► Show Figures

Figure 1

16 pages, 4441 KiB

Open AccessArticle

Effects of Larval Starvation Stress on the Life History and Adult Fitness of Fall Webworm, Hyphantria Cunea

by Yuan Zhang, Lin Zhang, Junchao Zheng, Tongpu Li and Lvquan Zhao

Insects 2025, 16(4), 410; https://doi.org/10.3390/insects16040410 - 14 Apr 2025

Viewed by 378

Abstract

Insects often encounter starvation stress, especially during invasion spread or population outbreaks. The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), is an important invasive pest in China, and the starvation resistance of its larvae determines population spread and resulting outbreak threat. In this [...] Read more.

Insects often encounter starvation stress, especially during invasion spread or population outbreaks. The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), is an important invasive pest in China, and the starvation resistance of its larvae determines population spread and resulting outbreak threat. In this study, we investigated the starvation resistance of H. cunea larvae and the effects of starvation stress on their life history and adult fitness. Larval starvation resistance increased along with the instar stage, and the second-day sixth instar molt was critical for starvation resistance. The response to starvation stress was reflected in multiple biological indicators observed in H. cunea. Complete food deprivation reduced the pupation survival rate of sixth instar larvae, prolonged their developmental duration, reduced pupal and adult body mass, shortened adult forewing length and lifespan, and reduced female egg production. The sixth instar larvae showed a certain ability to recover after refeeding. However, negative impacts of the starvation period on larval life history traits, such as pupation survival rate, pupal and adult body mass, adult longevity, and fecundity, were still observed even after refeeding, and the effects of refeeding were affected by larval starvation duration and refeeding mode. These results suggested that H. cunea larvae were highly resistant to starvation, that starvation stress negatively affected their larval life history and adult fitness, and that the pattern of the effects of post-starvation refeeding on larval and adult fitness was related to the duration of starvation and the refeeding mode. The results of this study offer important insights into understanding the physiological response mechanisms of invasive insects under starvation stress. Full article

(This article belongs to the Special Issue Arthropod Reproductive Biology)

► Show Figures

Figure 1

15 pages, 16273 KiB

Open AccessArticle

The Post-Invasion Population Dynamics and Damage Caused by Globose Scale in Central Eurasia: Destiny of Wild Apricot Still at Stake

by Ping Zhang, Yifan Li, Cuihong Li, Guizhen Gao, Zhaoke Dong, Elahe Rostami, Zhaozhi Lu and Myron P. Zalucki

Insects 2025, 16(4), 409; https://doi.org/10.3390/insects16040409 - 13 Apr 2025

Viewed by 297

Abstract

The globose scale (GS) Sphaerolecanium prunastri (Boyer de Fonscolombe) (Hemiptera: Coccidae) is a serious pest affecting plants within the Rosaceae, notably wild apricot, Armeniaca vulgaris (Lamarck). Following its initial detection in 2019, more than 80% of valleys with wild apricots have become affected [...] Read more.

The globose scale (GS) Sphaerolecanium prunastri (Boyer de Fonscolombe) (Hemiptera: Coccidae) is a serious pest affecting plants within the Rosaceae, notably wild apricot, Armeniaca vulgaris (Lamarck). Following its initial detection in 2019, more than 80% of valleys with wild apricots have become affected in the Ili River Basin of the Tianshan Mountains in Xinjiang, China. This study assessed GS population dynamics post invasion and its effects on the growth and reproductive traits of wild apricot trees from 2019 to 2024. Nymph densities have decreased but remain high, with densities per 20 cm of shoots of 986 (1^st-instar nymphs) and 120 (2^nd-instar nymphs) in 2024, respectively. Damage has declined, with high damage rankings decreasing from 24% to 11% of wild apricot trees. However, the mortality of trees was higher (25%) in infested than non-infested areas (13%). Interestingly, GS feeding stimulated the growth of spring shoots but significantly reduced the reproductive capacity of wild apricots. Heavily infested trees exhibited increased shoot length (2–3 times), decreased fruit yield (20-fold), lower flowering percentage (8-fold), and reduced flower bud density (2-fold) compared to non-infested trees. Overall, despite a decrease in damage severity, wild apricot forests remain threatened by GS. Implementing integrated pest management (IPM) strategies is essential for effective GS management and the recovery of wild apricot forests. Full article

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

► Show Figures

Figure 1

24 pages, 2558 KiB

Open AccessArticle

Age-Dependent Variation in Longevity, Fecundity and Fertility of Gamma-Irradiated Bagrada hilaris (Hemiptera: Pentatomidae): Insights for a Sustainable SIT Program

by Alessandra Paolini, Sergio Musmeci, Chiara E. Mainardi, Chiara Peccerillo, Alessia Cemmi, Ilaria Di Sarcina, Francesca Marini, René F. H. Sforza and Massimo Cristofaro

Insects 2025, 16(4), 408; https://doi.org/10.3390/insects16040408 - 13 Apr 2025

Viewed by 282

Abstract

Bagrada hilaris is an invasive stink bug causing important yield losses in Brassica crops. It originates from India, Southeast Asia, the Middle East and South Africa and is reported as invasive in several southwestern US states, Hawaii, Mexico, Chile and in the Mediterranean [...] Read more.

Bagrada hilaris is an invasive stink bug causing important yield losses in Brassica crops. It originates from India, Southeast Asia, the Middle East and South Africa and is reported as invasive in several southwestern US states, Hawaii, Mexico, Chile and in the Mediterranean islands of Malta and Pantelleria (Italy). In this study, we tested the effects of gamma rays on the longevity, fecundity and fertility of bagrada bugs. We irradiated them at two different stages of their life cycle (fifth-instar nymphs and two-week-old adults). Irradiation at the nymphal stage had a strong impact on female fecundity, with egg numbers approaching zero at a dose of 80 Gy. Similarly, a full suppression of female fertility was achieved at 80 Gy when they were mated with males irradiated as nymphs or as mature adults. For longevity, gamma rays had only a slight impact on adult male and female life span. Due to the evidence of a gregarious phase during the autumn, these results suggest that small-scale SIT-localized applications by massive collections of bagrada bugs at various stages of development during autumn, followed by irradiation and reintroduction to the field, might be a safe and economically sound approach of control. Research is currently underway to evaluate the fitness of sterile males and mating patterns. Further studies in confined-field conditions will be needed. Full article

(This article belongs to the Collection Hemiptera: Ecology, Physiology, and Economic Importance)

► Show Figures

Figure 1

13 pages, 2977 KiB

Open AccessArticle

Adipokinetic Hormones and Their Receptor Regulate the Locomotor Behavior in Tribolium castaneum

by Rui-Han Lu, Xu-Dong Pang, Shuang-Qin Wen, Guy Smagghe, Tong-Xian Liu and Shun-Hua Gui

Insects 2025, 16(4), 407; https://doi.org/10.3390/insects16040407 - 12 Apr 2025

Viewed by 316

Abstract

The regulation of locomotor behavior is essential for insects to perform their life activities. The central nervous system plays a pivotal role in modulating physiological behaviors, particularly movement, with neuropeptides serving as key modulators of these processes. Among these, adipokinetic hormone (AKH) was [...] Read more.

The regulation of locomotor behavior is essential for insects to perform their life activities. The central nervous system plays a pivotal role in modulating physiological behaviors, particularly movement, with neuropeptides serving as key modulators of these processes. Among these, adipokinetic hormone (AKH) was originally identified in insects as a neurohormone involved in lipid mobilization. This study investigates the functional role of AKHs (AKH1 and AKH2) and their receptor (AKHR) in regulating locomotion in the red flour beetle, Tribolium castaneum. Using functional calcium reporter assays, we demonstrated that AKHR is activated by two mature AKH peptides from T. castaneum, with half-maximal effective concentrations (EC₅₀) falling within the nanomolar range. Gene expression analysis confirmed the presence of AKH1 and AKH2 transcripts in the brain, while AKHR expression was localized to the fat body and carcass. The silencing of AKHs or AKHR through RNA interference resulted in a significant reduction in both movement distance and duration. Collectively, these findings highlight the regulatory influence of AKH/AKHR signaling in locomotor activity in T. castaneum, thereby advancing our understanding of the molecular mechanisms underlying locomotor control in this economically important insect species. Full article

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

► Show Figures

Figure 1

Journal Menu

Journal Browser

Insects, Volume 16, Issue 4 (April 2025) – 107 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI