모기류는 흡혈을 통해 원충, 바이러스, 사상충 등 다양한 병원체를 보유하며 말라리아, 일본뇌염, 웨스트나일 열, 뎅기열 등을 사람에게 매개하는 위해성이 있는 위생해충이다. 이번 연구에서는 해외유입 모기류 감시를 위해 경남 고성지역에 설치한 스마트 고공포집기를 이용하여 2022년부터 2023년까지 모기류들을 모니터링하였다. 조사기간 동안, 총 3속 5종 43개체가 채집되었으며, 이중 삼일열 말라리아를 매개하는 Anopheles belenrae를 경남 지역에서 처음으로 발생함을 확인하였다. 본 연구는 해외유입 모기류에 대한 감시망 구축의 최초 시도로서, 고공 포집기를 활용하여 모기류 감시가 가능함을 확인하였다.

Entomopathogenic fungi serve as eco-friendly alternatives to chemical pesticides. In this study, we investigate the interactions between mosquitoes and Metarhizium anisopliae JEF-157, which showed high insecticidal activity against mosquitoes, by RNA-seq analysis. RNA from mosquitoes was extracted at the median lethal time to identify changes in gene expression. The results showed 580 genes were up-regulated, while 336 genes were down-regulated in fungal treated mosquitoes. Up-regulated genes were related to metabolic and cellular processes such as cytochrome P450, DNA replication, and apoptosis. Down-regulated genes were involved in metabolism pathways such as lysosome, starch and sucrose metabolism, and fatty acid biosynthesis. These results are crucial for elucidating the mechanisms of fungal invasion and interaction in insects, providing insights for future pest management strategies.

Entomopathogenic fungi have been studied to control insect pests as an alternative to chemical insecticides. However, all fungi haven't a high virulence against pests. In this study, we compared the biological characteristics of Metarhizium anisopliae strains. First, we selected four M. anisopliae strains and compared the thermotolerance, conidial productivity, and virulence. For the thermotolerance test, conidial suspensions were exposed to 0, 30, 60, and 90 min at 45 °C. As a result, the conidial germination rates were over 95% when exposed for 0 min but, were 64, 37.7, 6, and 3% when exposed for 30 min at 45°C, respectively. To compare conidial productivity, 200g of millet were used and inoculated with a conidial suspension of 1 ml (1×107 conidia/ml). Conidial productivity was investigated after 14 days. As a result of conducting a virulence test against mealworms using a spray method, differences in virulence between strains were confirmed.

Western drywood termite, Incisitermes minor, is distributed southwestern USA and northern Mexico. Invasions had been reported to Canada, China, Hawaii and Japan. Incisitermes minor may be introduced through wooden structures. In California and Arizona, it caused economic damage of about $250 million. In September 2023, it was discovered in a house in Changwon-city, Korea and a joint investigation was conducted by APQA and other government agencies. The 16S rRNA sequence was used in the molecular epidemiological investigation to trace the origin of the invasion. Five individuals found in Changwon and 18 foreign sequences collected by NCBI were compared. A total of 462bp of base sequences were compared, and the genetic distance was observed to range from a minimum of 0.000 to a maximum of 0.1791. They were most genetically similar to the California individual in the United States.

Drywood termite (Cryptotermes domesticus), native to South East Asia, is distributed in India, China, Taiwan, Australia and so on. In China, it is considered an economically important pest causing damage to wood. It lives in dry wood environments such as furniture, buildings, and structural timber. It is difficult to find drywood termite within a structure but it can be detected by the presence of alate flight and small egg-like pellets of excreta. It was found in a house in Seoul, Korea in July 2023 and was investigated joint by APQA, National Institute of Ecology, National Institute Biological Resources, National Institute of Forest Science, Cultural Heritage Administration and Gyeongsang National University. The COII barcode region was analized with PCR method and compared with the sequences of all C. domesticus registered in NCBI 557bp of base sequence. Genetic difference ranged from a minimum of 0.0072 to a maximum of 0.0557. Among these, the individual with the minimum genetic distance was from Guangdong Province, China.

Hemipsocus chloroticus (Hagen, 1858) is a leaf litter barklice and has been recorded in Japan, China, Taiwan, South-East Asia, Sri Lanka, and North America. We collected H. chloroticus on Jinju-si, Sanchung-gun, Seoguipo-si, and Ulsan-si from 2022 to 2023. In this study, H. chloroticus is reported for the first time in Korea, and illustrations of diagonistic characters are provided.

The Genus Greenidea includes 66 species worldwide. Only two species have been recorded in Korea: G.kuwanai and G.nipponica. We collected Greenidea nigra Maki, 1917 on Quercus glauca in Jeju. This species has been recorded in Japan and Taiwan. In this study, we report this species for the first time in South Korea, and describe morphological features of apterous viviparous females.

The yellow mealworm beetle, Tenebrio molitor L. (Coleoptera: Tenebrionidae), has long been used as a key study organism in many fundamental researches, including biochemistry, physiology, and behavior. Lifespan and reproduction are two of the most important components of fitness in all insects, but it remains largely unexplored how these two traits are influenced by macronutrient intake in this beetle. In this study, we used the nutritional geometry framework to analyze the complex and interactive effects of dietary protein and carbohydrate intake on lifespan and reproductive performance in T. molitor beetle. Lifespan and the number of eggs laid throughout the lifetime were quantified from more than 2,000 individual beetles provided with one of 35 chemically defined diets representing a full combination of seven protein-to-carbohydrate ratios (P:C= 0:1, 1:5, 1:2, 1:1, 2:1, 5:1, or 1:0) and five protein plus carbohydrate concentrations (P+C=25.2, 33.6, 42, 50.4, or 58.8 %, dry mass). All measures of lifespan and egg production were expressed highly at high caloric intake, but they differed in the optimal P:C ratio where traits peaked. While lifespan was the longest at a moderately carbohydrate-biased P:C ratio of 1:1.36, the rate of egg production was maximized at a protein-biased P:C ratio of 1.75:1, suggesting a possible nutrient-mediated trade-off between lifespan and daily reproductive efforts in T. molitor beetles. Lifetime egg production was maximized at a P:C ratio of 1.31:1, which was still protein-biased but lower than that maximized egg production rate. Reproductive lifespan was the longest at a P:C ratio of 1:1.06. When given a food choice, T. molitor beetles preferred a P:C ratio of 1:1, which is closest to the ratio that enables T. molitor beetles to stay reproductively active as long as possible.

Calonecrinae represent a unique but small subfamily of Nitidulidae that is endemic to South Asia. Their habitats, the South Asian lowland forests, are under the imminent threat of degradation, posing a risk of rapid extinction for these species in their specific locales. Despite the looming threat to their existence, our understanding of this enigmatic group remains limited. We conducted an examination of museum and newly collected specimens, alongside a review of the literature, leading to the discovery of a new species, Calonecrus mindanaoensis, from Mindanao, Philippines. For the first time, the morphology of all immature stages of the Calonecrinae was described, with detailed photographs including SEM images. Additionally, their natural history was uncovered for the first time, revealing that all life stages are uniquely adapted to spending their entire life cycle within sticky resin. We re-evaluated the phylogenetic placement of the Calonecrinae by constructing a phylogenetic tree based on the mitochondrial genome. Calonecrinae are positioned within the Epuraeinae clade and show significant affinity with the genus Trimenus. Consequently, this study proposes reclassifying Calonecrinae as Calonecrini stat nov, an extremely modified tribe within the Epuraeinae.

In vertebrates, it is well documented that the parental consumption of high-fat diet increases the risk of Attention-Deficit Hyperactivity Disorder (ADHD) in offspring. While insects have long been used as popular study organisms in various biological research, few studies have explored how the nutritional quality of parental diet affects offspring behavioral phenotypes associated with ADHD in insects. Here we used the bean bug, Riptortus pedestris (Hemiptera: Alydidae), as a study organism to test the effect of parental high-fat diet on offspring hyperactivity, impulsivity, and diffuse attention, which are widely held as the three core symptoms of ADHD in vertebrates. Peanut was used as the high-fat diet while soybean was the control. Parental high-fat diet consumption induced hyperactivity in R. pedestris offspring. Compared to the controls, the hyperactive offspring of parents fed on high-fat diet were behaviorally more impulsive and less attentive, as they were found to be highly attracted to visual stimuli but losing attention easily. Collectively, these results provide the experimental evidence that the parental consumption of high-fat diet results in increased hyperactivity, impulsivity, and diffuse attention in an insect. This study implies that the well-known association between parental high-fat diet and offspring ADHD is conserved across the tree of life and opens up the new horizons that insects can arise as novel and feasible models for studying the mechanism and evolution of this common neurodevelopmental disorder in humans.

Pyrethroid resistance in cockroach populations has been a public health challenge since the 1950s. The pyrethroid resistance in the German cockroach, Blattella germanica, is primarily attributed to knockdown resistance (kdr) mutations (E434K, C764R, and L993F) in the voltage-sensitive sodium channel gene (vssc). In this study, the pyrethroid resistance state of the German cockroach in the Republic of Korea (ROK) was assessed by analyzing the frequencies of kdr mutations using one-step PCR with total RNA. The results revealed that among the 25 populations examined, 14 populations exhibited the L993F kdr mutation, while no other mutations were detected. Since other cockroach species are also commonly found in human dwellings in ROK, the vssc genes were cloned from four other species, including Blattella nipponica, Periplaneta americana, Periplaneta japonica, and Periplaneta fuliginosa. Based on the genomic DNA (gDNA) sequences obtained from the vssc cloning, primer sets were designed to amplify the vssc fragment spanning the L993F mutation for each species and used to monitor the development of pyrethroid resistance in cockroach populations in the ROK. The study will facilitate the implementation of a nationwide monitoring program to assess cockroach resistance and select suitable alternatives.

Acetylcholinesterase (AChE) is a key enzyme that terminates impulse transmission by rapidly hydrolyzing the neurotransmitter acetylcholine at cholinergic synapses. Previous studies have discovered a transiently opening channel referred to as the “back door” in Torpedo californica AChE. Previously, we observed that substituting the Tyr391 residue with a Phe residue significantly decreased the catalytic efficiency of recombinant Apis mellifera AChE1 (AmAChE1), while the reverse substitution restored it. Interestingly, substitution of the Tyr391 residue with a Phe residue in AmAChE1 disrupted the formation of the backdoor, while the reverse substitution restored it. This finding suggests that the Tyr-to-Phe substitution impairs backdoor formation, thereby leading to a significant reduction in the catalytic activity of AmAChE1. This serves as one of the driving forces for the functional transition from AmAChE1 to AmAChE2. In this experiment, we also confirmed the gradual restoration and increase in AChE activity by substituting Phe391 in AmAChE1 with Ser, Trp, Thr, Ile, Asn, and Tyr residues through kinetic assay and molecular dynamics simulation.

Salt is crucial for survival, yet excessive intake of sodium chloride can have adverse effects. In the fruit fly, Drosophila melanogaster, internal taste organs located in the pharynx play a pivotal role in determining whether to accept or reject food. However, our understanding of how pharyngeal gustatory receptor neurons (GRNs) perceive high salt levels is still limited. In this study, we discovered that a specific member of the ionotropic receptor family, Ir60b, is selectively expressed in a pair of GRNs that respond to high salt concentrations. Through a two-way choice assay (DrosoX) to measure ingestion volume, we established that IR60b, along with two coreceptors, IR25a and IR76b, is necessary to deter excessive salt consumption. Interestingly, mutants lacking external taste organs but retaining internal taste organs in the pharynx showed significantly higher salt avoidance compared to flies missing all three IRs while still possessing all taste organs. These findings underscore the crucial role of IRs in pharyngeal GRNs in regulating the intake of high salt levels.

To overcome the challenges in tracking insects underground, a detection method consisting of a metal detector and aluminum tag was developed for tracking a dung beetle, Copris ochus (Coleoptera: Scarabaeidae). First, detection rate was evaluated for varying volumes of aluminum tags varying orientations of the tags under soil. Then, the detection efficacy was evaluated in the field at varying depths of hidden tags in two types of vegetation. Finally, the effect of aluminum-tagging on the survivorship, burrowing depth, and horizontal movement of C. ochus adults were assessed. Generally, an increase in tag volume resulted in a greater detection depth with maximum depth of 17 cm. Orientation, however, did not affect detection rate except when tag was placed perpendicular to the soil surface. In the field, metal detectors could detect aluminum-tagged models with success rates ≥85% up to 10 cm and 45−60% at 20 cm under soil. Finally, no significant effect of tagging on survivorship and behaviors of C. ochus was observed.

Riptortus pedestris is known to acquire their symbiotic bacteria, Caballeronia insecticola, from soil environments in every generation. The symbionts have been demonstrated to affect behavioral and physiological traits of the host insect such as the enhancement of development. In particular, symbiotic effects on female adults could directly entail changes in their population growth. Therefore, we investigated a suite of symbiotic effects of C. insecticola on behaviors and fitness-related parameters of female R. pedestris. Overall, symbiotic females showed an behavioral enhancement in both feeding efficacy and movement capacity including walking and flight. In addition, the survival rates under exposure to overwintering conditions and insecticide resistance level were significantly higher in symbiotic females than the aposymbiotic. Finally, although symbiotic females exhibited shorter longevity, their fecundity was found higher compared to the apo-symbiotic.