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Insects, Volume 15, Issue 7 (July 2024) – 95 articles

Cover Story (view full-size image): The brown marmorated stink bug, Halyomorpha halys, originally from Asia, has become a pest in various parts of the world. The sterile insect technique (SIT), which involves sterilizing insects through ionizing radiation before releasing them into a field, is one method for controlling this pest. This study investigates the ultrastructure of H. halys spermiogenesis in both irradiated and non-irradiated males. Typical hemipteran sperm characteristics were observed. Additionally, as shown in these two images, two centrioles were sometimes observed in spermatids, with one disappearing as time progressed—an unprecedented feature in insect spermiogenesis. In irradiated adults, the cysts displayed inconsistent radiation effects, such as disorganized sperm arrangement, incomplete cell divisions, multiple organelles within single cells, failure to reabsorb cytoplasm, and the absence of axonemes. View this paper
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14 pages, 3210 KiB  
Article
Cascaded Aggregation Convolution Network for Salient Grain Pests Detection
by Junwei Yu, Shihao Chen, Nan Liu, Fupin Zhai and Quan Pan
Insects 2024, 15(7), 557; https://doi.org/10.3390/insects15070557 - 22 Jul 2024
Viewed by 461
Abstract
Pest infestation poses significant threats to grain storage due to pests’ behaviors of feeding, respiration, excretion, and reproduction. Efficient pest detection and control are essential to mitigate these risks. However, accurate detection of small grain pests remains challenging due to their small size, [...] Read more.
Pest infestation poses significant threats to grain storage due to pests’ behaviors of feeding, respiration, excretion, and reproduction. Efficient pest detection and control are essential to mitigate these risks. However, accurate detection of small grain pests remains challenging due to their small size, high variability, low contrast, and cluttered background. Salient pest detection focuses on the visual features that stand out, improving the accuracy of pest identification in complex environments. Drawing inspiration from the rapid pest recognition abilities of humans and birds, we propose a novel Cascaded Aggregation Convolution Network (CACNet) for pest detection and control in stored grain. Our approach aims to improve detection accuracy by employing a reverse cascade feature aggregation network that imitates the visual attention mechanism in humans when observing and focusing on objects of interest. The CACNet uses VGG16 as the backbone network and incorporates two key operations, namely feature enhancement and feature aggregation. These operations merge the high-level semantic information and low-level positional information of salient objects, enabling accurate segmentation of small-scale grain pests. We have curated the GrainPest dataset, comprising 500 images showcasing zero to five or more pests in grains. Leveraging this dataset and the MSRA-B dataset, we validated our method’s efficacy, achieving a structure S-measure of 91.9%, and 90.9%, and a weighted F-measure of 76.4%, and 91.0%, respectively. Our approach significantly surpasses the traditional saliency detection methods and other state-of-the-art salient object detection models based on deep learning. This technology shows great potential for pest detection and assessing the severity of pest infestation based on pest density in grain storage facilities. It also holds promise for the prevention and control of pests in agriculture and forestry. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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15 pages, 1162 KiB  
Article
The Effects of Natural Insecticides on the Green Peach Aphid Myzus persicae (Sulzer) and Its Natural Enemies Propylea quatuordecimpunctata (L.) and Aphidius colemani Viereck
by Francesco Lami, Giovanni Burgio, Serena Magagnoli, Laura Depalo, Alberto Lanzoni, Elettra Frassineti, Ilaria Marotti, Mattia Alpi, Dario Mercatante, Maria Teresa Rodriguez-Estrada, Giovanni Dinelli and Antonio Masetti
Insects 2024, 15(7), 556; https://doi.org/10.3390/insects15070556 - 22 Jul 2024
Viewed by 451
Abstract
Botanical insecticides and soaps are frequently proposed as environmentally safer alternatives to synthetic insecticides. However, the efficacy and selectivity of these products are often only partially supported by empirical evidence. Here, we tested the effectiveness of five botanical insecticides, belonging to different categories, [...] Read more.
Botanical insecticides and soaps are frequently proposed as environmentally safer alternatives to synthetic insecticides. However, the efficacy and selectivity of these products are often only partially supported by empirical evidence. Here, we tested the effectiveness of five botanical insecticides, belonging to different categories, on the green peach aphid Myzus persicae (Sulzer) and their selectivity towards two natural enemies, the ladybird beetle Propylea quatuordecimpunctata (L.) and the parasitoid Aphidius colemani (Dalman). White thyme essential oil (EO), sweet orange EO, crude garlic extract and Marseille soap were tested and compared with a pyrethrin-based commercial product. Both direct spray assays and residual contact assays on treated cabbage leaf disks were carried out. The tested products had low efficacy against aphids when compared to pyrethrins but were in general less detrimental to ladybird beetle larvae, meaning that if applied against other pests, they have a lower chance of harming this agent of aphid biocontrol. Some of the products (soap, orange EO) did, however, show direct exposure toxicity toward ladybird larvae, and thyme EO had extensive phytotoxic effects on cabbage leaves, possibly indirectly leading to higher mortality in ladybird adults. These results underline the necessity for case-by-case evaluations of botanical insecticides. Full article
(This article belongs to the Special Issue Chemical Toxicology and Insecticide Resistance on Insect Pests)
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12 pages, 3539 KiB  
Article
Expression and Functional Analysis of the Smo Protein in Apis mellifera
by Lina Guo, Jue Wang, Diandian Yu, Yu Zhang, Huiman Zhang and Yuan Guo
Insects 2024, 15(7), 555; https://doi.org/10.3390/insects15070555 - 22 Jul 2024
Viewed by 524
Abstract
Smoothened (Smo) is a critical component regulating the Hedgehog signaling pathway. However, whether Smo is associated with the modulation of olfactory recognition capabilities of bees remains unclear. In this study, we amplified Smo from Apis mellifera. The coding sequence of Smo [...] Read more.
Smoothened (Smo) is a critical component regulating the Hedgehog signaling pathway. However, whether Smo is associated with the modulation of olfactory recognition capabilities of bees remains unclear. In this study, we amplified Smo from Apis mellifera. The coding sequence of Smo was 2952 bp long, encoded 983 amino acids. Smo was most highly expressed in the antennae. Cyclopamine (200 μg/mL) significantly reduced but purmorphamine (800 μg/mL) significantly increased Smo expression (p < 0.05). OR152 and OR2 expression in the cyclopamine group significantly decreased, whereas OR152 expression in the purmorphamine group significantly increased (p < 0.05). A significant decrease in the relative values of electroantennography was observed in the cyclopamine group exposed to neral. Behavioral tests indicated a significant decrease in the attractive rates of neral, VUAA1, linalool, and methyl heptenone in the cyclopamine group. Conversely, the selection rates of linalool and methyl heptenone in the purmorphamine group significantly increased. Our findings indicate that Smo may play a role in modulating olfactory receptors in bees. Full article
(This article belongs to the Collection Insect Signals)
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15 pages, 1213 KiB  
Article
Comparative Transcriptome Analysis Reveals Different Responses in Three Developmental Stages of Mythimna loreyi to Cold Stress
by Yun Duan, Qi Chen, Muhammad Bilal, Yuqing Wu, Zhongjun Gong, Renhai Wu and Jin Miao
Insects 2024, 15(7), 554; https://doi.org/10.3390/insects15070554 - 22 Jul 2024
Viewed by 525
Abstract
The loreyi leafworm Mythimna loreyi (Lepidoptera: Noctuidae) is a serious pest of agriculture that causes particular damage to Gramineae crops in Asia, Europe, Australia, Africa, and the Middle East. Low temperature is one of the important environmental factors that limits the survival, distribution, [...] Read more.
The loreyi leafworm Mythimna loreyi (Lepidoptera: Noctuidae) is a serious pest of agriculture that causes particular damage to Gramineae crops in Asia, Europe, Australia, Africa, and the Middle East. Low temperature is one of the important environmental factors that limits the survival, distribution, colonization, and abundance of M. loreyi. However, the metabolic synthesis pathways of cold-tolerant substances in M. loreyi and the key genes involved in the regulation under cold stress remain largely unknown. In this study, we sequenced the transcriptomes of three developmental stages (larvae, pupae, and adults) of M. loreyi to discover the molecular mechanisms of their responses to cold stress. In total, sequencing generated 120.64 GB of clean data from 18 samples, of which 19,459 genes and 1740 differentially expressed genes (DEGs) were identified. The enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that many DEGs were mainly enriched in pathways associated with energy metabolism and hormone metabolism. Among these, genes encoding multiple metabolic enzymes, cuticle proteins (CPs), and heat shock proteins (HSPs) were differentially expressed. These results indicate that there are significant differences among the three developmental stages of M. loreyi exposed to cold stress and provide a basis for further studying the molecular mechanisms of cold tolerance in insects. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
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71 pages, 39462 KiB  
Article
Taxonomic Revision of the Nearctic Genus Drepanaphis Del Guercio (Hemiptera, Aphididae: Drepanosiphinae)
by Kamila Malik, Agnieszka Bugaj-Nawrocka and Karina Wieczorek
Insects 2024, 15(7), 553; https://doi.org/10.3390/insects15070553 - 21 Jul 2024
Viewed by 407
Abstract
The Nearctic aphid genus Drepanaphis Del Guercio, 1909, the largest within the subfamily Drepanosiphinae (Hemiptera: Aphididae), is characterised by distinctive dorsal abdominal tubercles. This study presents a comprehensive taxonomic revision of the genus, expanding the recognised species to 18, including the newly described [...] Read more.
The Nearctic aphid genus Drepanaphis Del Guercio, 1909, the largest within the subfamily Drepanosiphinae (Hemiptera: Aphididae), is characterised by distinctive dorsal abdominal tubercles. This study presents a comprehensive taxonomic revision of the genus, expanding the recognised species to 18, including the newly described Drepanaphis robinsoni Malik sp. nov. Detailed descriptions and figures for 44 morphs, encompassing alate viviparous females, oviparous females and males, are provided, with new identification keys for all known species and morphs. The sexual morphs of 15 species, particularly oviparous females, are documented for the first time. Morphometric and principal component analyses (PCA) are employed to distinguish the studied taxa. This study identifies and corrects numerous misidentifications in museum collections, previously labelled as D. acerifoliae, D. choanotricha, D. kanzensis, D. knowltoni, D. parva, D. sabrinae or D. tissoti. Furthermore, it revalidates the distinct status of D. nigricans and D. tissoti, which had been synonymised in earlier works. Current range maps for all species and images of key morphological features obtained through light and scanning electron microscopy are also presented, providing a more complete understanding of this understudied genus. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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12 pages, 3192 KiB  
Article
Patterns and Drivers of Bumblebee Diversity in Gansu
by Muhammad Naeem, Huanhuan Chen, Wenbo Li, Alice C. Hughes, Paul H. Williams, Nawaz Haider Bashir, Zhengying Miao, Jiaxing Huang and Jiandong An
Insects 2024, 15(7), 552; https://doi.org/10.3390/insects15070552 - 21 Jul 2024
Viewed by 603
Abstract
Understanding the influence of factors responsible for shaping community assemblage is crucial for biodiversity management and conservation. Gansu is one of the richest regions for bumblebee species in the world. We explored the distribution data of 52 bumblebee species collected in Gansu and [...] Read more.
Understanding the influence of factors responsible for shaping community assemblage is crucial for biodiversity management and conservation. Gansu is one of the richest regions for bumblebee species in the world. We explored the distribution data of 52 bumblebee species collected in Gansu and its surroundings between 2002 and 2022, predicting habitat suitability based on 17 environmental variables using MaxEnt. The factors influencing community assemblage were assessed using canonical correspondence analysis. Net primary productivity, water vapor pressure, temperature seasonality, annual precipitation, and precipitation seasonality were some of the most influential drivers of species distributions. Based on Ward’s agglomerative cluster analysis, four biogeographic zones are described: the Southern humid zone, the Western Qilian snow mountain zone, the Eastern Loess plateau zone, and the Western dry mountain zone. In the clusters of grid cells based on beta diversity values, the Southern humid zone comprised 42.5% of the grid cells, followed by the Eastern Loess plateau zone (32.5%), the Western dry mountain zone (20%), and the Western Qilian snow mountain zone (5%). Almost all the environmental factors showed a significant contribution to the assemblages of bumblebees of different groups. Our findings highlight the need for better data to understand species biogeography and diversity patterns, and they provide key baseline data for refining conservation strategies. Full article
(This article belongs to the Section Insect Societies and Sociality)
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14 pages, 1489 KiB  
Article
Can the Necrophagous Blow Fly Calliphora vicina (Diptera: Calliphoridae) Be Reared on Plant-Based Meal?
by David F. Cook, Muhammad Shoaib Tufail and Sasha C Voss
Insects 2024, 15(7), 551; https://doi.org/10.3390/insects15070551 - 21 Jul 2024
Viewed by 850
Abstract
The use of the blow fly Calliphora vicina as a potential pollination species to augment the current reliance on honeybees (Apis mellifera) in Australian horticulture requires knowledge of how best to mass-rear this fly species. Calliphora vicina lays eggs onto carrion [...] Read more.
The use of the blow fly Calliphora vicina as a potential pollination species to augment the current reliance on honeybees (Apis mellifera) in Australian horticulture requires knowledge of how best to mass-rear this fly species. Calliphora vicina lays eggs onto carrion soon after death, and the resultant larvae that hatch are necrophagous and feed on the decomposing tissues of the dead animal. Newly hatched larvae of this fly were provided with plant-based meals (soya bean and canola) and compared with larvae provided with livestock-derived meatmeal to determine if plant-based meal could be used to mass-rear this blow fly species. Both soya bean and canola meal media did not support larval survival through to adult emergence. The addition of only 10% whole egg powder to the plant-based meals enabled survival to eclosion of 39% and 13% on soya bean and canola-based media, respectively, compared with 76% on livestock-based meatmeal with 10% whole egg powder. Larvae fed a diet of livestock-based meatmeal with 10% whole dried egg powder had the fastest development to the pupal stage, the highest pupation rate, the heaviest pupae, and the highest subsequent adult eclosion. This study concluded that the use of plant-based meals as a diet for the mass-rearing of the blow fly C. vicina was not a viable option. Full article
(This article belongs to the Collection Science of Insect Rearing Systems)
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11 pages, 1021 KiB  
Article
Development Modeling of Phormia regina (Diptera: Calliphoridae)
by Amanda Roe, Jeffrey D. Wells and Leon G. Higley
Insects 2024, 15(7), 550; https://doi.org/10.3390/insects15070550 - 21 Jul 2024
Viewed by 461
Abstract
A series of experiments were conducted on Phormia regina, a forensically important blow fly species, that met the requirements needed to create statistically valid development models. Experiments were conducted over 11 temperatures (7.5 to 32.5 °C, at 2.5 °C intervals) with a [...] Read more.
A series of experiments were conducted on Phormia regina, a forensically important blow fly species, that met the requirements needed to create statistically valid development models. Experiments were conducted over 11 temperatures (7.5 to 32.5 °C, at 2.5 °C intervals) with a 16:8 L:D cycle. Experimental units contained 20 eggs, 10 g of beef liver, and 2.5 cm of sand. Each life stage (egg to adult) had five sampling times. Each sampling time was replicated four times for a total of 20 measurements per life stage. For each sampling time, the cups were pulled from the chambers, and the stage of each maggot was documented morphologically through posterior spiracular slits and cephalopharyngeal development. Data were normally distributed with the later larval (L3m) and pupation stages having the most variation within and transitioning between stages, particularly between 12.5 °C and 20.0 °C. The biological minimum was between 10.0 °C and 12.5 °C, with little egg development and no egg emergence at 7.5 °C and no maturation past L1 at 10.0 °C. Phormia regina did not display increased mortality associated with the upper temperature of 32.5 °C. The development data generated illustrate the advantages of large data sets in modeling blow fly development and the need for curvilinear models in describing development at environmental temperatures near the biological minima and maxima. Full article
(This article belongs to the Collection Advances in Diptera Biology)
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12 pages, 2069 KiB  
Article
New COI-COII mtDNA Region Haplotypes in the Endemic Honey Bees Apis mellifera intermissa and Apis mellifera sahariensis (Hymenoptera: Apidae) in Algeria
by Amira Chibani Bahi Amar, Nacera Tabet Aoul, Riad Fridi, Alain Vignal and Kamila Canale-Tabet
Insects 2024, 15(7), 549; https://doi.org/10.3390/insects15070549 - 20 Jul 2024
Viewed by 527
Abstract
The practice of beekeeping in Algeria is of great cultural, social, and economic importance. However, the importation of non-local subspecies reported by beekeepers has disrupted the natural geographical distribution area and the genetic diversity of the native honey bees. To assess the genetic [...] Read more.
The practice of beekeeping in Algeria is of great cultural, social, and economic importance. However, the importation of non-local subspecies reported by beekeepers has disrupted the natural geographical distribution area and the genetic diversity of the native honey bees. To assess the genetic diversity of A. m. intermissa and A. m. sahariensis, and their relationships with African and European subspecies, the COI-COII intergenic region was analyzed in 335 individuals, 68 sampled in Algeria, 71 in Europe, Madagascar, and the South West Indian Ocean archipelagos, and 196 sequences recovered from GenBank. The results show the presence of the A lineage exclusively in Algerian samples with the identification of 24 haplotypes of which 16 are described for the first time. These haplotypes were found to be shared by both subspecies, with A74 being the most common haplotype in the population studied. The sequence comparison indicates the existence of three polymorphisms of the COI-COII marker: P0Q, P0QQ, and P0QQQ. One new haplotype was identified in the M lineage in samples from France. No evidence of genetic introgression within the Algerian honey bee population was detected. These data enhance our knowledge of the genetic diversity and emphasize the importance of protecting these local subspecies. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
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15 pages, 1591 KiB  
Article
VOC Characterization of Byasa hedistus (Lepidoptera: Papilionidae) and Its Visual and Olfactory Responses during Foraging and Courtship
by Mingtao Li, Jie Liu, Shunan Chen, Jun Yao, Lei Shi, Hang Chen and Xiaoming Chen
Insects 2024, 15(7), 548; https://doi.org/10.3390/insects15070548 - 19 Jul 2024
Viewed by 443
Abstract
Color and odor are crucial cues for butterflies during foraging and courtship. While most sexual dimorphic butterflies rely more on vision, our understanding of how butterflies with similar coloration use different signals remains limited. This study investigated the visual and olfactory behavioral responses [...] Read more.
Color and odor are crucial cues for butterflies during foraging and courtship. While most sexual dimorphic butterflies rely more on vision, our understanding of how butterflies with similar coloration use different signals remains limited. This study investigated the visual and olfactory behavioral responses of the similarly colored butterfly Byasa hedistus during foraging and courtship. While visiting artificial flowers of different colors, we found that B. hedistus exhibits an innate color preference, with a sequence of preferences for red, purple, and blue. The frequency of flower visits by B. hedistus significantly increased when honey water was sprayed on the artificial flowers, but it hardly visited apetalous branches with honey water. This proves that locating nectar sources by odor alone is difficult in the absence of floral color guides. During courtship, males are active while females hardly chase; only two models were observed: males chasing males and males chasing females. The courtship process includes four behaviors: slowing approach, straight chasing, hovering, and spinning. B. hedistus cannot distinguish between sexes based on color, as there is no significant difference in color and shape between them. Twenty-three VOCs (>1%) were identified in B. hedistus, with 21 shared by both sexes, while ketones are specific to males. These VOCs are principally represented by cineole, β-pinene, and linalool. When cineole was added to butterfly mimics, many butterflies were attracted to them, but the butterflies did not seem to distinguish between males and females. This suggests that cineole may be the feature VOC for identifying conspecific groups. Adding β-pinene and linalool to mimics induced numerous butterflies to chase, hover, spin around, and attempt to mate with them. This suggests that β-pinene and linalool are crucial cues indicating the presence of females. Full article
(This article belongs to the Section Insect Physiology, Reproduction and Development)
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12 pages, 1940 KiB  
Article
Predatory Potential of Nymphal Odonates on Aedes aegypti Developing in Freshwater and Brackish Water Habitats
by Sivasingham Arthiyan, Thampoe Eswaramohan, Andrew Hemphill and Sinnathamby Noble Surendran
Insects 2024, 15(7), 547; https://doi.org/10.3390/insects15070547 - 19 Jul 2024
Viewed by 414
Abstract
Aedes aegypti, the primary vector of dengue, undergoes preimaginal development in brackish water (BW). However, dengue vector control exclusively targets freshwater (FW) habitats. The present study evaluated the predatory efficacy of nymphal odonates that can develop in both FW and BW. Nymphs [...] Read more.
Aedes aegypti, the primary vector of dengue, undergoes preimaginal development in brackish water (BW). However, dengue vector control exclusively targets freshwater (FW) habitats. The present study evaluated the predatory efficacy of nymphal odonates that can develop in both FW and BW. Nymphs of three damselfly and three dragonfly species from FW and BW habitats were identified and acclimatized to FW (<0.5 gL−1 salt) and BW (10 gL−1 salt) mesocosm conditions. The experiment was repeated nine times with nine different individual predators per species under both salinity conditions. One hundred L3 Ae. aegypti from FW and BW laboratory colonies were introduced to determine the predatory rate (PR) and clearance rate (CR) after 24, 48, and 72 h, and one hundred L3 larvae were introduced every 24 h. The dragonfly nymph Hydrobasileus croceus and the damselfly nymph Paracercion hieroglyphicum showed the highest PR and CR under both rearing conditions at all times. However, damselfly and dragonfly nymphs significantly (p < 0.05) differed in their CR under both FW and BW conditions. Thus, all six odonate species have predatory potential and this suggests that they could be used as biological control agents to eliminate preimaginal stages of Ae. aegypti developing in both FW and BW habitats. Full article
(This article belongs to the Section Medical and Livestock Entomology)
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17 pages, 7202 KiB  
Article
Future Range Expansions of Invasive Wasps Suggest Their Increasing Impacts on Global Apiculture
by Xueyou Zhang, Peixiao Nie, Xiaokang Hu and Jianmeng Feng
Insects 2024, 15(7), 546; https://doi.org/10.3390/insects15070546 - 19 Jul 2024
Viewed by 454
Abstract
Until now, no study has examined the future range dynamics of major invasive wasp species to assess their future impacts on global apiculture. Here, we developed 12 species distribution models to calibrate the future range dynamics of 12 major invasive Vespidae wasp species [...] Read more.
Until now, no study has examined the future range dynamics of major invasive wasp species to assess their future impacts on global apiculture. Here, we developed 12 species distribution models to calibrate the future range dynamics of 12 major invasive Vespidae wasp species under a unified framework. An increase in their habitat suitability was identified in more than 75% of global land. Substantial range expansions were detected for all 12 species, and they were primarily induced by future climate changes. Notably, Polistes dominula and Vespa crabro had the largest potential ranges under all scenarios, suggesting their greater impact on global apiculture. Polistes chinensis and Vespa velutina nigrithorax had the highest range expansion ratios, so they warrant more urgent attention than the other species. Polistes versicolor and P. chinensis are expected to exhibit the largest centroid shifts, suggesting that substantial shifts in prioritizing regions against their invasions should be made. Europe and the eastern part of the USA were future invasion hotspots for all major invasive wasp species, suggesting that apiculture might face more pronounced threats in these regions than in others. In conclusion, given their substantial range shifts, invasive wasps will likely have increasingly negative impacts on global apiculture in the future. Full article
(This article belongs to the Section Insect Ecology, Diversity and Conservation)
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24 pages, 3912 KiB  
Article
Cryptic Taxa Revealed through Combined Analysis of Chromosomes and DNA Barcodes: The Polyommatus ripartii Species Complex in Armenia and NW Iran
by Vladimir A. Lukhtanov and Alexander V. Dantchenko
Insects 2024, 15(7), 545; https://doi.org/10.3390/insects15070545 - 19 Jul 2024
Viewed by 332
Abstract
The detection of cryptic species in complexes that have undergone recent speciation is often difficult, since many standard nuclear markers have not yet accumulated differences between closely related taxa, and differences in mitochondrial markers can be leveled out due to mitochondrial introgressions. In [...] Read more.
The detection of cryptic species in complexes that have undergone recent speciation is often difficult, since many standard nuclear markers have not yet accumulated differences between closely related taxa, and differences in mitochondrial markers can be leveled out due to mitochondrial introgressions. In these cases, the use of derived chromosomal characters such as non-ancestral chromosomal numbers and/or unusual karyotype features may be a solution to the species delimitation problem. However, non-ancestral but similar karyotypes may arise secondarily as a result of homoplastic evolution, and their interpretation as homologies may lead to incorrect taxonomic conclusions. In our study, we show that the combined use of mitochondrial DNA barcodes and karyotypes helps to solve this problem and identifies cryptic species in situations where each of these markers does not work individually. Using this approach, we show that the fauna of Armenia and adjacent Iran includes the following cryptic taxa of the Polyommatus ripartii species complex (haploid chromosome number, n in parentheses): P. ripartii paralcestis (n = 90), P. ripartii kalashiani, subsp. nov (n close to 90), P. emmeli, sp. nov. (n = 77–79), P. keleybaricus, sp. nov. (n = 86), P. demavendi belovi (n = 73–75), P. demavendi antonius, subsp. nov. (n = 71–73), P. admetus anatoliensis (n = 79) and P. eriwanensis (n = 29–34). Polyommatus admetus yeranyani is synonymized with P. admetus anatoliensis. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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15 pages, 9205 KiB  
Article
Taxonomic Impediment for Conservation: The Case of Bees in an Undersampled Tropical Mid-Elevation Site, San Martín, Peru
by Claus Rasmussen and Evelyn Sánchez
Insects 2024, 15(7), 544; https://doi.org/10.3390/insects15070544 - 18 Jul 2024
Viewed by 1093
Abstract
In this first field survey of an entire bee fauna for any part of Peru, we report a total of 1796 bees belonging to 181 species or morphospecies in four families. The taxonomic impediment was pronounced with only 80 species of 181 that [...] Read more.
In this first field survey of an entire bee fauna for any part of Peru, we report a total of 1796 bees belonging to 181 species or morphospecies in four families. The taxonomic impediment was pronounced with only 80 species of 181 that could be named. With such a high proportion of undetermined species, it is not possible to adequately compare pollinator communities across different studies, assess historical changes or analyze endemism patterns to document ecology, behavior and evolution of the species and genera. This information is required to provide a sound basis for policymakers to protect habitats for the conservation of native pollinators. Full article
(This article belongs to the Special Issue Bee Conservation: Behavior, Health and Pollination Ecology)
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15 pages, 1674 KiB  
Article
Influence of Distance, Environmental Factors, and Native Vegetation on Honeybee (Apis mellifera) Foraging in Arid Shrublands and Grasslands
by Alma Delia Baez-Gonzalez, Mario Humberto Royo-Marquez, Carlos Alejandro Perez-Quintana, Adrián Isaac Hernández-Bernal, Alicia Melgoza-Castillo, Mieke Titulaer and Jose Humberto Vega-Mares
Insects 2024, 15(7), 543; https://doi.org/10.3390/insects15070543 - 18 Jul 2024
Viewed by 415
Abstract
This study determined the influence of foraging distance, environmental factors, and native vegetation on honeybee (Apis mellifera) foraging in arid shrublands and grasslands in Northern Mexico. Apiary distance from inflorescence sites did not have a significant influence on the intensity of [...] Read more.
This study determined the influence of foraging distance, environmental factors, and native vegetation on honeybee (Apis mellifera) foraging in arid shrublands and grasslands in Northern Mexico. Apiary distance from inflorescence sites did not have a significant influence on the intensity of foraging. Apiary location and landscape were decisive factors in the response of honeybees to environmental factors. Air temperature, minimum temperature, wind velocity, and relative humidity explained foraging by 87, 80, 68, and 41% (R2), respectively, in shrubland sites in open landscapes but had no significant influence on foraging in the grassland sites in a valley surrounded by hills (1820–2020 amsl). Nights with a minimum temperature of <20 °C increased foraging activity during the day. Minimum temperature, which has the least correlative influence among climate elements, can be used to determine climate change’s impact on bees. The quantity of available inflorescence explained the foraging intensity by 78% in shrublands and 84% in grasslands. Moreover, when honeybees depended mainly on native vegetation in grasslands, the quantity of inflorescence explained the intensity of foraging by 95%. High intensity of honeybee foraging was observed in allthorn (Koeberlinia spinosa) and wait-a-minute bush (Mimosa aculeaticarpa) in shrublands and honey mesquite (Neltuma glandulosa) and wait-a-minute bush (Mimosa aculeaticarpa) in grasslands. The findings and baseline data contributed by this study may be used to identify suitable environments for increasing apiary productivity and other agricultural and ecological benefits. Full article
(This article belongs to the Section Insect Ecology, Diversity and Conservation)
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14 pages, 4231 KiB  
Article
Acoustic Communication in Dendroctonus adjunctus Blandford (Curculionidae Scolytinae): Description of Calls and Sound Production Mechanism
by León L. Cerrillo-Mancilla, Claudia Cano-Ramírez and Gerardo Zúñiga
Insects 2024, 15(7), 542; https://doi.org/10.3390/insects15070542 - 18 Jul 2024
Viewed by 362
Abstract
The acoustic communication system (ACS) in bark beetles has been studied mainly in species of the genera Dendroctonus, Ips and Polygraphus. Specifically, ACS of the roundheaded pine beetle, Dendroctonus adjunctus, has been little studied. In this study, we described the [...] Read more.
The acoustic communication system (ACS) in bark beetles has been studied mainly in species of the genera Dendroctonus, Ips and Polygraphus. Specifically, ACS of the roundheaded pine beetle, Dendroctonus adjunctus, has been little studied. In this study, we described the stridulatory apparatus of this beetle using optical and scanning electron microscopy and recorded the call types produced by males in three behavioral contexts: stress, female–male–, and male–male interactions. From the spectrograms and waveforms, call types, as well as temporal (tooth strike, tooth strike rate, and intertooth strike interval) and spectral features (minimum, maximum and dominant frequency), were determined. Males have a functional elytro–tergal stridulatory apparatus—females do not—consisting of a file for the pars stridens and two lobes for the plectrum. Most of spectro–temporal features were statistically different between single– and multi–noted calls and across the three behavioral contexts. In the male–male interaction, a new type of call named “withdrawal” was produced by the male withdrawing or fleeing. Our results suggest that the spectro–temporal features of single– and multiple–noted calls in the three behavioral conditions are specific and different from each other. Yet, the combination of single and multiple calls determines an overall calling pattern characteristic of the tested behaviors and, therefore, is species–specific. Full article
(This article belongs to the Section Insect Behavior and Pathology)
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12 pages, 933 KiB  
Article
Resource Utilization of Residual Organic Sludge Generated from Bioenergy Facilities Using Hermetia illucens Larvae
by Kyu-Shik Lee, Eun-Young Yun and Tae-Won Goo
Insects 2024, 15(7), 541; https://doi.org/10.3390/insects15070541 - 18 Jul 2024
Viewed by 354
Abstract
Residual organic sludge generated from bioenergy facilities (BF-rOS) is often disposed instead of recycled, thus contributing to further environmental pollution. This study explored the resource utilization of BF-rOS using Hermetia illucens larvae (BSFL). When BF-rOS was fed to BSFL for two weeks, the [...] Read more.
Residual organic sludge generated from bioenergy facilities (BF-rOS) is often disposed instead of recycled, thus contributing to further environmental pollution. This study explored the resource utilization of BF-rOS using Hermetia illucens larvae (BSFL). When BF-rOS was fed to BSFL for two weeks, the dry weight per individual BSFL was approximately 15% of that of BSFL that were fed food waste (FW). However, the dry weight increased by approximately two-fold in BSFL that were fed effective microorganism (EM)-supplemented BF-rOS containing 60% moisture. However, under both conditions, the BSFL did not mature into pupae. In contrast, the highest dry weight per BSFL was observed with the BF-rOS/FW (50%:50%) mixture, regardless of EM supplementation. Furthermore, the highest bioconversion rate was observed when the BSFL were fed the BF-rOS/FW (50%:50%) mixture, and the frass produced by the BSFL contained fertilizer-appropriate components. In addition, the nutritional components of the BSFL exhibited a nutrient profile suitable for animal feed, except for those fed BF-rOS only. In conclusion, this investigation demonstrates that BF-rOS should be recycled for fertilizer production by mixing it with FW as a BSFL feed, which generates the valuable insect biomass as potential nutrition for animal feeding. Full article
(This article belongs to the Special Issue Insects and Their Derivatives for Human Practical Uses 2nd Edition)
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15 pages, 2119 KiB  
Review
Advances in the Integrated Pest Management of Quinoa (Chenopodium quinoa Willd.): A Global Perspective
by Luis Cruces, Eduardo de la Peña and Patrick De Clercq
Insects 2024, 15(7), 540; https://doi.org/10.3390/insects15070540 - 18 Jul 2024
Viewed by 465
Abstract
Since ancestral times, quinoa (Chenopodium quinoa Willd.) has been cultivated in the Andean regions. Recently, this pseudocereal has received increasing international attention due to its beneficial properties, such as adaptation and resilience in the context of global change, and the nutritional value [...] Read more.
Since ancestral times, quinoa (Chenopodium quinoa Willd.) has been cultivated in the Andean regions. Recently, this pseudocereal has received increasing international attention due to its beneficial properties, such as adaptation and resilience in the context of global change, and the nutritional value of the grains. As a result, its production areas have not only increased in the highlands of South America but have also expanded outside of its Andean origins, and the crop is currently produced worldwide. The key pests of quinoa in the Andean region are the gelechiid moths Eurysacca melanocampta and Eurysacca quinoae; in other parts of the world, new pest problems have recently been identified limiting quinoa production, including the gelechiid Scrobipalpa atripicella in North America and Europe and the agromyzid fly Amauromyza karli in North America. In this review, the status of quinoa pests in the world is presented, and different aspects of their integrated management are discussed, including sampling methodologies for pest monitoring, economic threshold levels, and various control strategies. Full article
(This article belongs to the Collection Integrated Pest Management of Crop)
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18 pages, 1383 KiB  
Article
Beekeepers Support the Use of RNA Interference (RNAi) to Control Varroa destructor
by Rose McGruddy, John Haywood and Philip J. Lester
Insects 2024, 15(7), 539; https://doi.org/10.3390/insects15070539 - 18 Jul 2024
Viewed by 654
Abstract
Current Varroa mite management strategies rely heavily on the use of pesticides, adversely affecting honey bee health and leaving toxic residues in hive products. To explore the likelihood of RNAi technology being utilised as an alternative control method for pests like Varroa, [...] Read more.
Current Varroa mite management strategies rely heavily on the use of pesticides, adversely affecting honey bee health and leaving toxic residues in hive products. To explore the likelihood of RNAi technology being utilised as an alternative control method for pests like Varroa, the opinions of beekeepers on the use of this new biotechnology were obtained using a mixed-methodology approach. In-person surveys and focus groups using the Q method were conducted to discover the willingness of beekeepers to utilise Varroa-targeting RNAi treatments in their hives, and to gain feedback to inform decisions before the implementation of this new technology. Overall, the beekeepers saw potential in RNAi being used to control Varroa in their hives and were eager to have access to an alternative to pesticide treatments. Participants raised concerns about unknown long-term effects on bees and other non-target species, and the potential of an uninformed public preventing them from accessing a new Varroa treatment. While further research and discussion is needed before RNAi treatments for Varroa become commercially available, RNAi technology presents a promising, species-specific and non-toxic solution for Varroa management. Full article
(This article belongs to the Section Insect Societies and Sociality)
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2 pages, 135 KiB  
Correction
Correction: Prasad et al. Patterns of Variation in the Usage of Fatty Acid Chains among Classes of Ester and Ether Neutral Lipids and Phospholipids in the Queensland Fruit Fly. Insects 2023, 14, 873
by Shirleen S. Prasad, Matthew C. Taylor, Valentina Colombo, Heng Lin Yeap, Gunjan Pandey, Siu Fai Lee, Phillip W. Taylor and John G. Oakeshott
Insects 2024, 15(7), 538; https://doi.org/10.3390/insects15070538 - 18 Jul 2024
Viewed by 209
Abstract
Supplementary Table S3 in our recent publication [...] Full article
12 pages, 3077 KiB  
Article
Molecular Identification of the Glutaredoxin 5 Gene That Plays Important Roles in Antioxidant Defense in Arma chinensis (Fallou)
by Qiaozhi Luo, Zhongjian Shen, Nipapan Kanjana, Xingkai Guo, Huihui Wu and Lisheng Zhang
Insects 2024, 15(7), 537; https://doi.org/10.3390/insects15070537 - 17 Jul 2024
Viewed by 384
Abstract
Glutaredoxin (Grx) is a group of redox enzymes that control reactive oxygen species (ROS), traditionally defined as redox regulators. Recent research suggested that members of the Grx family may be involved in more biological processes than previously thought. Therefore, we cloned the AcGrx5 [...] Read more.
Glutaredoxin (Grx) is a group of redox enzymes that control reactive oxygen species (ROS), traditionally defined as redox regulators. Recent research suggested that members of the Grx family may be involved in more biological processes than previously thought. Therefore, we cloned the AcGrx5 gene and identified its role in A. chinensis diapause. Sequence analysis revealed the ORF of AcGrx5 was 432 bp, encoding 143 amino acids, which was consistent with the homologous sequence of Halyomorpha halys. RT-qPCR results showed that AcGrx5 expression was the highest in the head, and compared with non-diapause conditions, diapause conditions significantly increased the expression of AcGrx5 in the developmental stages. Further, we found that 15 °C low-temperature stress significantly induced AcGrx5 expression, and the expression of antioxidant enzyme genes AcTrx2 and AcTrx-like were significantly increased after AcGrx5 knockdown. Following AcGrx5 silencing, there was a considerable rise in the levels of VC content, CAT activity, and hydrogen peroxide content, indicating that A. chinensis was exposed to high levels of reactive oxygen species. These results suggested that the AcGrx5 gene may play a key role in antioxidant defense. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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15 pages, 3527 KiB  
Article
Spatio-Temporal Influence on the Distribution of Forensically Relevant Blowflies (Diptera: Calliphoridae) in Gyeongsangnam-do, South Korea
by Hyeon-Seok Oh, In-Seong Baek, Min-Gyu Kang and Sang-Hyun Park
Insects 2024, 15(7), 536; https://doi.org/10.3390/insects15070536 - 17 Jul 2024
Viewed by 373
Abstract
The study of blowfly (Diptera: Calliphoridae) biodiversity and distribution is crucial for forensic investigations. Abiotic and biotic factors, such as season and habitat type, have a significant impact on blowfly populations. However, only a few forensic entomology studies have been conducted in South [...] Read more.
The study of blowfly (Diptera: Calliphoridae) biodiversity and distribution is crucial for forensic investigations. Abiotic and biotic factors, such as season and habitat type, have a significant impact on blowfly populations. However, only a few forensic entomology studies have been conducted in South Korea, particularly in the Gyeongsangnam-do region. To address this, an extensive year-long survey was conducted to analyze the compositions, habitat preferences, distribution, and seasonal abundance of forensically relevant blowflies in urban and forested habitats of Gyeongsangnam-do, with sampling conducted twice a month using mouse carcass-baited traps set for 48 h each time. A total of 3470 adult blowflies were recorded, encompassing five genera and 13 species, with a noted absence of specimens during the winter months. The predominant species was Lucilia porphyrina, accounting for 37.2% of the total sample, followed by Chrysomya pinguis (27.6%), Lucilia sericata (7.6%), and Lucilia illustris (7.1%). The species composition was consistent across all surveyed regions; however, seasonal variation in species diversity was evident, with a peak in spring and a decline in summer. Notably, certain species exhibited clear preferences for either urban (Calliphora calliphoroides and L. sericata) or forested habitats (L. porphyrina and Ch. pinguis). This pioneering study elucidates the diverse blowfly communities in Gyeongsangnam-do, highlighting significant seasonal and habitat-dependent variations. These findings enrich our understanding of blowfly ecology in this region, offering valuable insights for forensic applications and underscoring the necessity for ongoing entomological surveillance and research. Full article
(This article belongs to the Section Medical and Livestock Entomology)
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24 pages, 43777 KiB  
Article
Socket Array Irregularities and Wing Membrane Distortions at the Eyespot Foci of Butterfly Wings Suggest Mechanical Signals for Color Pattern Determination
by Yugo Nakazato and Joji M. Otaki
Insects 2024, 15(7), 535; https://doi.org/10.3390/insects15070535 - 16 Jul 2024
Viewed by 521
Abstract
Eyespot foci on butterfly wings function as organizers of eyespot color patterns during development. Despite their importance, focal structures have not been examined in detail. Here, we microscopically examined scales, sockets, and the wing membrane in the butterfly eyespot foci of both expanded [...] Read more.
Eyespot foci on butterfly wings function as organizers of eyespot color patterns during development. Despite their importance, focal structures have not been examined in detail. Here, we microscopically examined scales, sockets, and the wing membrane in the butterfly eyespot foci of both expanded and unexpanded wings using the Blue Pansy butterfly Junonia orithya. Images from a high-resolution light microscope revealed that, although not always, eyespot foci had scales with disordered planar polarity. Scanning electron microscopy (SEM) images after scale removal revealed that the sockets were irregularly positioned and that the wing membrane was physically distorted as if the focal site were mechanically squeezed from the surroundings. Focal areas without eyespots also had socket array irregularities, but less frequently and less severely. Physical damage in the background area induced ectopic patterns with socket array irregularities and wing membrane distortions, similar to natural eyespot foci. These results suggest that either the process of determining an eyespot focus or the function of an eyespot organizer may be associated with wing-wide mechanics that physically disrupt socket cells, scale cells, and the wing membrane, supporting the physical distortion hypothesis of the induction model for color pattern determination in butterfly wings. Full article
(This article belongs to the Section Insect Physiology, Reproduction and Development)
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17 pages, 3177 KiB  
Article
Emerald Ash Borer Infestation-Induced Elevated Negative Correlations and Core Genera Shift in the Endophyte Community of Fraxinus bungeana
by Hua-Ling Wang, Zhen-Zhu Chen, Tuuli-Marjaana Koski, Bin Zhang, Xue-Fei Wang, Rui-Bo Zhang, Ruo-Qi Li, Shi-Xian Wang, Jian-Yong Zeng and Hui-Ping Li
Insects 2024, 15(7), 534; https://doi.org/10.3390/insects15070534 - 14 Jul 2024
Viewed by 1129
Abstract
Endophytes, prevalent in plants, mediate plant–insect interactions. Nevertheless, our understanding of the key members of endophyte communities involved in inhibiting or assisting EAB infestation remains limited. Employing ITS and 16S rRNA high-throughput sequencing, along with network analysis techniques, we conducted a comprehensive investigation [...] Read more.
Endophytes, prevalent in plants, mediate plant–insect interactions. Nevertheless, our understanding of the key members of endophyte communities involved in inhibiting or assisting EAB infestation remains limited. Employing ITS and 16S rRNA high-throughput sequencing, along with network analysis techniques, we conducted a comprehensive investigation into the reaction of endophytic fungi and bacteria within F. bungeana phloem by comparing EAB-infested and uninfected samples. Our findings reveal that EAB infestation significantly impacts the endophytic communities, altering both their diversity and overall structure. Interestingly, both endophytic fungi and bacteria exhibited distinct patterns in response to the infestation. For instance, in the EAB-infested phloem, the fungi abundance remained unchanged, but diversity decreased significantly. Conversely, bacterial abundance increased, without significant diversity changes. The fungi community structure altered significantly, which was not observed in bacteria. The bacterial composition in the infested phloem underwent significant changes, characterized by a substantial decrease in beneficial species abundance, whereas the fungal composition remained largely unaffected. In network analysis, the endophytes in infested phloem exhibited a modular topology, demonstrating greater complexity due to an augmented number of network nodes, elevated negative correlations, and a core genera shift compared to those observed in healthy phloem. Our findings increase understanding of plant–insect–microorganism relationships, crucial for pest control, considering endophytic roles in plant defense. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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17 pages, 7081 KiB  
Article
Comparative Analysis of the Mitochondrial Genomes of Three Species of Yangiella (Hemiptera: Aradidae) and the Phylogenetic Implications of Aradidae
by Liangpeng Ji, Zhancheng Jia and Xiaoshuan Bai
Insects 2024, 15(7), 533; https://doi.org/10.3390/insects15070533 - 14 Jul 2024
Viewed by 548
Abstract
The mitochondrial genomes of three species of Yangiella were sequenced, annotated, and analyzed. The genome length of the three species of the genus is 15,070–15,202 bp, with a typical gene number, including a control region, 2 ribosomal RNA genes (rRNAs), 22 transfer RNA [...] Read more.
The mitochondrial genomes of three species of Yangiella were sequenced, annotated, and analyzed. The genome length of the three species of the genus is 15,070–15,202 bp, with a typical gene number, including a control region, 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and 13 protein-coding genes (PCGs). It was found that the mitochondrial genome of Yangiella had AT bias. Except for the lack of a DHU arm of the trnS1 gene, the other tRNAs had a typical cloverleaf structure, and the codon usage preferences of the three species exhibited high similarity. In addition, tRNA gene rearrangements were observed among the three subfamilies of Aradidae (Mezirinae, Calisiinae, Aradinae), and it was found that codon usage preferences appeared to be less affected by base mutation and more by natural selection. The Pi and Ka/Ks values indicated that cox1 was the most conserved gene in the mitochondrial genome of Aradidae, while atp8 and nad6 were rapidly evolved genes. Substitution saturation level analysis showed that the nucleic acid sequence of mitochondrial protein-coding genes in Aradidae did not reach saturation, suggesting the rationality of the phylogenetic analysis data. Bayesian and maximum likelihood methods were used to analyze the phylogeny of 16 species of Hemiptera insects, which supported the monophyly of Aneurinae, Carventinae, and Mezirinae, as well as the monophyly of Yangiella. Based on fossils and previous studies, the differentiation time was inferred, indicating that Yangiella diverged about 57 million years ago. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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17 pages, 8343 KiB  
Article
Ultrastructure and Spectral Characteristics of the Compound Eye of Asiophrida xanthospilota (Baly, 1881) (Coleoptera, Chrysomelidae)
by Zu-Long Liang, Tian-Hao Zhang, Jacob Muinde, Wei-Li Fan, Ze-Qun Dong, Feng-Ming Wu, Zheng-Zhong Huang and Si-Qin Ge
Insects 2024, 15(7), 532; https://doi.org/10.3390/insects15070532 - 13 Jul 2024
Viewed by 624
Abstract
In this study, the morphology and ultrastructure of the compound eye of Asi. xanthospilota were examined by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), micro-computed tomography (μCT), and 3D reconstruction. Spectral sensitivity was investigated by electroretinogram (ERG) tests and phototropism experiments. [...] Read more.
In this study, the morphology and ultrastructure of the compound eye of Asi. xanthospilota were examined by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), micro-computed tomography (μCT), and 3D reconstruction. Spectral sensitivity was investigated by electroretinogram (ERG) tests and phototropism experiments. The compound eye of Asi. xanthospilota is of the apposition type, consisting of 611.00 ± 17.53 ommatidia in males and 634.8 0 ± 24.73 ommatidia in females. Each ommatidium is composed of a subplano-convex cornea, an acone consisting of four cone cells, eight retinular cells along with the rhabdom, two primary pigment cells, and about 23 secondary pigment cells. The open type of rhabdom in Asi. xanthospilota consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells (R1~R6) and two distally attached rhabdomeric segments generated solely by R7, while R8 do not contribute to the rhabdom. The orientation of microvilli indicates that Asi. xanthospilota is unlikely to be a polarization-sensitive species. ERG testing showed that both males and females reacted to stimuli from red, yellow, green, blue, and ultraviolet light. Both males and females exhibited strong responses to blue and green light but weak responses to red light. The phototropism experiments showed that both males and females exhibited positive phototaxis to all five lights, with blue light significantly stronger than the others. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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9 pages, 1812 KiB  
Article
The Comparative Field Evaluation of Four Different Traps for Mosquito Surveillance in the Republic of Korea
by Hak Seon Lee, Byung-Eon Noh, Seong Yoon Kim, Hyunwoo Kim and Hee Il Lee
Insects 2024, 15(7), 531; https://doi.org/10.3390/insects15070531 - 13 Jul 2024
Viewed by 739
Abstract
Monitoring mosquito populations is essential for controlling mosquito-borne diseases, and the selection of mosquito traps should be tailored to specific surveillance objectives. Here, we tested four mosquito traps for their efficiency and applicability: the Nozawa-style black light trap (BLT), BG-sentinel trap II (BGT), [...] Read more.
Monitoring mosquito populations is essential for controlling mosquito-borne diseases, and the selection of mosquito traps should be tailored to specific surveillance objectives. Here, we tested four mosquito traps for their efficiency and applicability: the Nozawa-style black light trap (BLT), BG-sentinel trap II (BGT), UV-LED Blackhole Plus Mosquito Buster trap (LED), and digital mosquito monitoring system (DMS). The traps were rotated weekly for a 24 h cycle at the same location for 13 weeks. Overall, 1649 female mosquitoes belonging to seven genera and sixteen species were collected by the traps. The traps exhibited differences in both the number of collected individuals and species composition. The BLT showed superior collection efficiency in terms of the number of collected individuals and species evenness, whereas the BGT showed the highest species diversity among all the traps. Thus, the BLT and BGT are the best choices for effective mosquito surveillance based on trap performance. Additionally, despite the relatively low efficiency of the LED and DMS observed in this study, the LED is known to be efficient when used for indoor conditions such as cowsheds, while the DMS has an advanced function that can automatically count the number of mosquitoes. Thus, our findings provide significant guidelines for planning new mosquito surveillance projects in the ROK. Full article
(This article belongs to the Section Medical and Livestock Entomology)
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18 pages, 6637 KiB  
Article
The Food Source and Gut Bacteria Show Effects on the Invasion of Alien Pests—A Case of Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)
by Yanfei Zhu, Rui Han, Tong Zhang, Jiawen Yang, Ziwen Teng, Yinjun Fan, Pengdong Sun, Yongyue Lu, Yonglin Ren, Fanghao Wan and Hongxu Zhou
Insects 2024, 15(7), 530; https://doi.org/10.3390/insects15070530 - 13 Jul 2024
Viewed by 566
Abstract
How alien pests invade new areas has always been a hot topic in invasion biology. The spread of the Bactrocera dorsalis from southern to northern China involved changes in food sources. In this paper, in controlled conditions, we take Bactrocera dorsalis as an [...] Read more.
How alien pests invade new areas has always been a hot topic in invasion biology. The spread of the Bactrocera dorsalis from southern to northern China involved changes in food sources. In this paper, in controlled conditions, we take Bactrocera dorsalis as an example to study how plant host transformation affects gut bacteria by feeding it its favorite host oranges in the south, its favorite host peaches and apples in the north, and feeding it cucumbers as a non-favorite host plant, thereby further affecting their fitness during invasion. The result showed that, after three generations of feeding on cucumbers, Bactrocera dorsalis took longer to develop as a larva while its longevity and fecundity decreased and pre-adult mortality increased. Feeding it cucumbers significantly reduced the overall diversity of gut microbiota of Bactrocera dorsalis. The relative abundance of Enterobacter necessary for survival decreased, while the Empedobacter and Enterococcus increased, resulting in decreased carbohydrate transport and metabolism and increased lipid transport and metabolism. Feeding Bactrocera dorsalis Empedobacter brevis and Enterococcus faecalis resulted in a 26% increase in pre-adult mortality and a 2–3 d increase in adult preoviposition period (APOP). Additionally, Enterococcus faecalis decreased the longevity of female and male adults by 17 and 12 d, respectively, and decreased fecundity by 11%. We inferred that the shifted plant hosts played an important role in posing serious harm to Bactrocera dorsalis invading from the south to the north. Therefore, after an invasion of Bactrocera dorsalis into northern China, it is difficult to colonize cucumbers for a long time, but there is still a risk of short-term harm. The findings of this study have established that the interactions between an insect’s food source and gut bacteria may have an important effect on insect invasions. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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15 pages, 2906 KiB  
Article
Intergenerational Sublethal Effects of Flonicamid on Cotton Aphid, Aphis gossypii: An Age-Stage, Two-Sex Life Table Study
by Hina Gul, Ali Güncan, Farman Ullah, Nicolas Desneux and Xiaoxia Liu
Insects 2024, 15(7), 529; https://doi.org/10.3390/insects15070529 - 13 Jul 2024
Viewed by 419
Abstract
Flonicamid is a novel systemic insecticide widely used against aphids. However, the intergenerational sublethal effects of flonicamid on cotton aphid, Aphis gossypii, have not been fully studied. This study aimed to evaluate the sublethal effects of flonicamid on the biological parameters of adult [...] Read more.
Flonicamid is a novel systemic insecticide widely used against aphids. However, the intergenerational sublethal effects of flonicamid on cotton aphid, Aphis gossypii, have not been fully studied. This study aimed to evaluate the sublethal effects of flonicamid on the biological parameters of adult A. gossypii (F0) and its subsequent intergenerational effects on the offspring (F1 generation) through age-stage, two-sex life table analysis. The results of the bioassays indicate that flonicamid exhibits significant toxicity toward adult A. gossypii, as evidenced by an LC50 value of 0.372 mg L−1 after a 48-h exposure period. The longevity, fecundity, and reproductive days of adult cotton aphids (F0) were significantly decreased when treated with the sublethal concentrations of flonicamid. The pre-adult stage exhibited an increase, whereas the adult longevity, total longevity, and fecundity experienced a notable decrease in F1 aphids after the exposure of F0 aphids to sublethal concentrations of flonicamid. Furthermore, the key demographic parameters, including r, λ, R0, and RPd, showed a significant decrease, while the total pre-reproductive period (TPRP) experienced a significant increase in the F1 generation. Collectively, our findings indicate that sublethal concentrations of flonicamid impact the demographic parameters of A. gossypii, resulting in suppression of population growth. This study presents comprehensive information on the overall impact of flonicamid on A. gossypii, which could potentially aid in managing this major pest. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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19 pages, 10925 KiB  
Article
Functional Morphology and Ultrastructure of the Peripheral Antennal Sensillar System of Graphosoma italicum (Müller, 1766) (Insecta: Hemiptera: Pentatomidae)
by Jolanta Brożek, Izabela Poprawa, Piotr Wegierek and Adam Stroiński
Insects 2024, 15(7), 528; https://doi.org/10.3390/insects15070528 - 12 Jul 2024
Viewed by 577
Abstract
The antennae of the shield bug Graphosoma italicum (Müller, 1766) were examined through scanning and transmission electron microscopy to reveal their general morphology, as well as the antennal sensilla’s distribution, size, and ultrastructure of their dendrites and function. The antennae comprise five antennomeres [...] Read more.
The antennae of the shield bug Graphosoma italicum (Müller, 1766) were examined through scanning and transmission electron microscopy to reveal their general morphology, as well as the antennal sensilla’s distribution, size, and ultrastructure of their dendrites and function. The antennae comprise five antennomeres (one scape, two pedicels, and two flagellomeres). Different lengths of chaetic mechanosensilla (Ch1-Ch4) exist on all antennomeres, and several highly sensitive campaniform sensilla are embedded in the exoskeleton and measure cuticular strain. One pair of peg sensilla, the typical proprioceptive, is only on the proximal edge of the first pedicel and directed to the distal edge of the scapus. The antennal flagellum possesses two subtypes of trichoid and basiconic sensilla, each with one type of coeloconic olfactory sensilla. The distinctive characteristics of G. italicum are also apparent in two subtypes of coeloconic sensilla embedded in different cavities on both antennomeres of the flagellum, probably with a thermo-hypersensitive function. All studied morphological types of the sensilla and their function were supported by ultrastructural elements. The long and thin trichoid sensilla type 2 (TrS2) with an olfactive function was the most abundant sensilla localized on both flagellomeres. The peripheral antennal sensilla system consists of six main types of sensilla divided into twelve subtypes. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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