Frontiers in insect science最新文献

Photoperiod is a critical environmental factor for insect development and physiology, yet little is known about the effects of photoperiodic signals received during photoperiod-sensitive stages on reproductive parameters. The green lacewing, Chrysoperla nipponensis, is a promising candidate for mass rearing in biological control. Photoperiod is the primary environmental factor influencing C. nipponensis reproductive diapause. This study investigates how photoperiodic cues during photoperiod-sensitive stages affect key reproductive parameters such as fecundity, lifespan, oviposition duration, oviposition rate, diapause rate, pre-oviposition period, and lipid content of C. nipponensis. The results showed that short-day conditions (Light:Dark = 9h:15h; L9:D15) during pre-adult stages increase total lipid and triglyceride levels in both third larvae and newly emerged females, thereby enhancing fecundity of female, without reducing lifespan or oviposition. Furthermore, long-day conditions (Light:Dark = 15h:9h; L15:D9) during the pre-adult stage inhibited diapause, while increasing fecundity and extending oviposition duration. Our findings demonstrate that photoperiodic signals during the pre-adult stages significantly affect the reproductive parameters of C. nipponensis, which advances the understanding of photoperiod-dependent reproductive diapause and offers novel insights for optimizing strategies in mass-rearing of natural enemies.

Introduction: The Aedes aegypti constitutes the primary vector for dengue fever, yellow fever, chikungunya, Zika, West Nile, and encephalitis viruses, all of which have impacted One Health (human, animal, and environmental health) significantly. It has been distributed widely in urban settings in Saudi Arabia, particularly in cities like Jeddah and Jizan, a situation that underscores the urgent need for innovative and sustainable vector control strategies. Molecular tools, such as DNA barcoding using mitochondrial markers, have become essential for identifying mosquito species accurately and understanding their role in disease transmission. Such knowledge is vital for informing effective, climate-resilient public health interventions.

Methods: This research focuses on identifying Aedes species in various regions of Saudi Arabia using polymerase chain reaction (PCR) and sequencing techniques, in order to evaluate the molecular diversity of these dengue vectors in Jeddah and Jizan. The study utilizes the cytochrome one oxidase (COI) gene as a molecular marker for phylogenetic analysis to compare the populations of Aedes species.

Results: The findings reveal the presence of significant genetic variation among mosquito populations. In the Jeddah region, the Ae. aegypti types MN299016.1 and KU495081.1 match completely (100%) the respective populations found in Argentina and Australia, with 93.1% (27/29) and 6.9% (2/29) respectively. Meanwhile, the samples from the Jizan region are 100% and 99.6% similar to the Ae. aegypti types MN298998.1, MK300226.1, PP892777.1, and MF043259.1 found in Canada, Kenya, India, and England.

Conclusion: This study underscores the necessity of using molecular techniques in vector surveillance to mitigate the spread of Zoonotic and vector borne diseases in Saudi Arabia. Moreover, these efforts align with the objectives of the Saudi Vision 2030 by promoting environmentally responsive vector surveillance in Jeddah and Jizan, thereby supporting integrated approaches to public health and ecological sustainability.

Over the years, most scholarly published papers have studied vertebrates, despite invertebrates' higher species diversity and number of individuals. This has led to an inaccurate representation of global biodiversity patterns in scientific publications. Furthermore, the bias for studying vertebrates is also evident when comparing studies conducted in the tropics vs. temperate zones. We investigated whether similar taxonomic and geographical biases are maintained in recent years when studying the behavior of Neotropical ants. We searched for papers published between 2015 and 2022 with the words "ant" OR "ants" OR formicidae; tropic* OR neotropic* and behav* AND tropic* OR neotropic*. We found that recently published papers studying ants cover only ~10% of the Neotropical ant species, with a primary focus on economically damaging and/or invasive ants. Our results revealed that studies on ant behavior in the Neotropics are dominated by four species, which represent less than 0.15% of the ant species in the Neotropics, and that 50% of the focal species were mentioned only once or twice in studies regarding behavior. Moreover, recent ant behavior studies cover only approximately 8% of the Neotropical ant biodiversity. We found that the Neotropical countries where most ants have been collected for behavioral studies are Brazil, Panama, and Costa Rica. In contrast, other Central American countries are absent from the recent ant literature. Our results reveal concerning patterns of taxonomic and geographical inequity in the study of Neotropical ant behavior, despite its potential role in managing ant invasions and ensuring effective conservation measures. We highlight the need to broaden behavioral studies in the Neotropics and urge researchers to investigate relatively unknown ant species, and include understudied countries with limited scientific resources to fill this critical gap in current ant research.

Introductiom: Habitat fragmentation alters environmental structure and imposes selective pressures on dispersal-related traits in insect vectors, potentially driving morphological adaptations that enhance flight performance. In this study, weinvestigate how landscape metrics influence the size and shape of the head and wings in two Triatominae species, Triatoma garciabesi and T. guasayana, which present differing ecological strategies. We hypothesize that individuals from more fragmented landscapes exhibit phenotypic shifts associated with enhanced dispersal capacity and increased morphological symmetry.

Methods: To test this, we combined community-based sampling of triatomines with geometric morphometrics and multiscale landscape metrics. We applied geometric morphometrics and generalized linear models (GLM)-based analyses to assess the effects of habitat fragmentation on flight-related morphology.

Results: Our results reveal that T. garciabesi shows increased head asymmetry and narrower wings in highly fragmented landscapes, while T. guasayana exhibits subtle shifts in head shape asymmetry and greater sexual dimorphism. In both species, head and wing sizes tended to be larger in fragmented habitats, especially in females, suggesting differential morphological responses that may reflect species-specific dispersal strategies.

Discussion: Habitat fragmentation differentially affects T. garciabesi and T. guasayana, leading to distinct dispersal syndromes. Triatoma garciabesi shows greater plasticity, highlighting the role of landscape structure in shaping adaptive dispersal traits.

Effective mosquito control is critical in swine production to reduce disease transmission and prevent mechanical damage. However, current biosecurity measures on swine premises primarily target microbial pathogens, often overlooking the importance of excluding insects, particularly mosquitoes. While vector-borne disease transmission is the primary concern, mosquito infestations also contribute to mechanical damage, leading to secondary infections, stress-related production losses, and compromised animal welfare. Mitigation efforts aimed at mosquitoes can also have broader benefits by reducing other insect pests that compromise swine health. Despite the availability of tools and strategies for mosquito monitoring and control, standardized protocols and evaluations of effectiveness remain limited. This study aims to assess the protective attributes of swine housing against mosquito threats and identify vulnerabilities that may increase the risk of insect-borne diseases. By understanding these factors, targeted biosecurity strategies can be developed to enhance insect exclusion and reduce the overall impact of mosquito infestations on swine health and production. A key focus of this assessment is the reduction of mosquito populations within and around swine housing facilities. By providing swine producers and veterinarians with actionable insights and practical mitigation strategies, this study seeks to strengthen mosquito management efforts, ultimately improving herd health, productivity, and overall biosecurity.

This study explores the transcriptional dynamics of the polyphagous Mexican Fruit Fly, Anastrepha ludens, across five developmental stages, revealing distinct gene expression patterns unique to each stage. We identified 9,762 DEGs associated with the four developmental stages. During the egg stage, we identified the greatest number of differentially expressed genes exhibiting a pronounced activity of metabolic pathways, particularly the Mitogen-Associated Protein Kinase (MAPK) signaling pathway, which is essential for embryonic development and defense mechanisms. The second larval instar stage mainly focused on growth, as shown by the overexpression of the Transforming Growth Factor Beta (TGF-beta) pathway. In the third larval stage, genes are significantly enriched in cuticle structure and transmembrane transport. In the pupal stage, the importance of the TGF-beta and mTOR pathways emerged, vital for tissue homeostasis and development. The adult stage exhibited sustained expression of the FOXO pathway, enhancing stress resistance crucial for survival and reproduction. Additionally, we noted differences in odor-binding protein (OBP) expression between sexes, hinting at their potential role in mating behavior. These findings provide fundamental information about the life stages of A. ludens, highlighting the importance of specific signaling pathways and OBPs, which could help improve mass rearing processes and management strategies for this notorious tephritid pest.

The red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae), a cosmopolitan stored-product pest frequently infesting sauce-flavor Daqu (a multi-microbial fermented starter), may experience mitochondrial genome variations under the selective pressure exerted by this enzyme-rich substrate. Here we test whether feeding on sauce-flavor Daqu is associated with mitogenomic differences in T. castaneum. We present the complete mitochondrial genome of T. castaneum from this environment: a 15,885 bp circular DNA (GenBank PV563855) retaining ancestral insect architecture with 71.81% A+T content and slight positive AT skew. The genome contains 37 functional elements: 22 tRNA genes (all exhibiting atypical cloverleaf structures except trnS1(AGN)), 13 protein-coding genes (PCGs), 2 rRNA genes, and a 1,238 bp A+T-rich control region (82.80% AT). Eleven PCGs initiate with ATN codons, while cox1 (CTG) and nad1 (TTG) show divergent initiation. Ten PCGs terminate with TAA/TAG codons. Gene order aligns with basal insect mitogenomes. Comparative analysis with Jiangsu (China) and California (USA) strains revealed conserved structural features, though sequence/assembly discrepancies require further investigation to assess potential pressure-induced mutations. While these differences may reflect adaptations to the enzyme-rich Daqu environment, technical and geographical factors could also contribute; further functional studies are needed to establish causal links.

Aim: The insect cuticle, vital for structural maintenance, forms their exoskeleton. It is mainly composed of an intermesh of - structural cuticle proteins (CPs) with polysaccharide chitin. The insect CPs encoded by CP genes are indispensable for morphology, development and adaptation to various ecological niches across all life stages. The number of CPs may vary across genera and species, with almost 150 proteins in Bombyx mori and more than 298 CPs found in Anopheles gambiae. While they have been extensively studied in insects such as agricultural pests, limited studies have been conducted on mosquitoes, particularly those relevant to public health, such as the Anopheles a key malaria vector.

Objective: This review recapitulates current knowledge on CPs in insects, while also underscoring vital knowledge gaps regarding regulation and metabolic crosstalk of CPs with other signaling and/or metabolic pathways.

Methods: We performed a comprehensive review of published studies and extracted data from databases including Vectorbase and NCBI with the aim of retrieving information on cuticular proteins, their gene families, abundance and associated functions. Additionally, we identified and analyzed the gaps in the available information. A literature search was conducted between (2000 and 2025) in an electronic database using PubMed, Scopus and Google Scholar. The search keywords were: cuticular proteins, cuticular genes, Anopheles, mosquito cuticle proteins, insecticide resistance, and CP gene families.Inclusion criteria: peer-reviewed research articles and review papers particularly focused on CPs in insects and Anopheles mosquito species.

Results: In the present review, we provide comprehensive analysis of cuticle protein families across insects including mosquitoes based on available data. We further highlight their basic constituents and protein domain structure, offering insight into their role in insect physiology. We have effectively integrated insect studies with mosquito-specific research on CPs (bridging the gap between insect and mosquito-specific research). This holistic approach would facilitate a broader comprehension of CPs in both insect and mosquito vectors.

Main conclusions: The goal of this study is to enhance our understanding of insects and Anopheles biology and how studies on CPs could be leveraged to develop novel strategy for management of pest and combat vector-borne diseases (VBDs).

Dung beetles (Coleoptera, Scarabaeoidea) support several ecological processes and services making them important ecosystem engineers. The dung beetle gut microbiota is involved in many of these ecological services. In the present study, we analyzed the microbiota of 90 individuals of three Onthophagus species feeding on different dung types. Our aim was to understand whether the species identity affected the microbiota more than the dung ingested and whether this conditioning applied equally to prokaryotes and fungi. We also compared the taxonomic and functional variability of the microorganisms to check for similarities between individuals. Using molecular analyses, we characterized the alpha and beta diversities, core and indicator taxa and taxonomic and functional composition of the gut microbiota. Alpha diversity analyses revealed diet, species and sex to influence diversity parameters but no clear differences in the diversity patterns for prokaryotes vs fungi. Conversely, all other analyses consistently showed differences in the composition patterns for prokaryotes vs fungi, with prokaryotes mostly varying according to host species identity and fungi varying according to dung type. This suggests that most prokaryotes in the dung beetle microbiota are definitive symbionts, whereas many fungi are transient symbionts. We found evidence of great similarity in the functional composition of the microbiota despite strong taxonomic dissimilarities. The results emphasize the need to consider both the prokaryotic and fungal components of the microbiota. They also suggest microbial composition analyses to be preferable to alpha diversity analyses for identifying patterns of variation that depend on phylogeny and diet.

The larvae of five dipteran species were reared on artificial diets under controlled laboratory conditions. Usually, these species complete their life cycles in perishable, filthy, unhygienic, and foul-smelling natural diets, which hinder rearing work and affect the laboratory environment. More importantly, these unaltered foods do not allow for true conformity in rearing protocols. The addition of a standard artificial diet to rearing protocols would make it possible to conduct ecological, biological, and forensic investigations with greater accuracy and precision. To address this problem, we formulated a new artificial diet for larvae and tested its performance on five different fly species (Calliphora vicina, Lucilia sericata, Sarcophaga argyrostoma, Musca domestica, and Hermetia illucens). We compared the development of larvae reared on an artificial diet with that of larvae reared on beef liver and pig muscle. The results showed no differences in development time between the two groups. However, our results showed that the artificial diet facilitated the rearing of flies for forensic and medical purposes by standardizing the nutritional value of the diet, improving laboratory conditions, and providing a more hygienic and cost-effective food substrate.