An outbreak of stick insects, Ramulus mikado, as forest pests in South Korea has become a topic of concern. While other countries have reported these insects being severely affected by the entomopathogenic fungus Metarhizium spp., comprehensive research in South Korea remains limited on this topic. In our two-year investigation, we investigated the infection rate and mortality of R. mikado caused by Metarhizium anisopliae. In 2022, specimens were collected from Cheonggyesan, and in 2023 from Geumamsan. Although no infections were confirmed in the specimens collected in June of both years. Beginning in July, mortality and infection rates were greatly increased. In conclusion, the summer monsoon appears to create hot and humid conditions in the forest, contributing to reduced survival rates for these insects due to infection by M. anisopliae.

대벌레(Ramulus mikado)는 1990년 이후부터 2000년대 초반까지 경북을 중심으로 대발생을 하였던 돌발 해충 으로 2020~2023년에 수도권에서 대발생 사례가 다수 보고 되었다. 대벌레의 대발생 원인으로 기후변화가 지목되 고 있지만, 대벌레 개체군과 생물적·비생물적 환경 조건과의 관계를 이해하기 위한 연구는 매우 부족한 실정이 다. 본 연구에서는 주요 기주식물과 대벌레 발생 양상에 대한 관계를 이해하고자 수행하였다. 2022년부터 2023년 까지 대벌레 대발생 지역 중 하나인 청계산 일대 등산로를 따라 조사구를 선정한 뒤 주요 기주식물이자 우점종인 신갈나무, 아까시나무, 잔털벚나무를 대상으로 대벌레의 발생 밀도를 조사하였다. 그 결과, 조사지점 간의 대벌 레 평균 밀도는 유의한 차이가 발견되지 않았지만, 기주식물에 따른 밀도의 차이는 뚜렷하게 나타났다.

The walking-stick insects, Ramulus mikado, are outbreaks in several mountainous areas from 2020 to 2022. In recent, some population of the insect are showed rapidly decline in their abundance, while some of them are still maintained high population density. In worldwide, insects belonging to Phasmida are reported to outbreak in their habitats as mentioned above environments, but knowledge about outbreak pattern of the walking-stick insects is still lacking. In this study, we aimed which biological and environmental factors are related to wax and wane of the insect population. From 2022 to 2023, we studied host tree preferences in natural conditions, ecological stoichiometry in major host trees, overwintering ecology of R. mikado eggs, and infection rate by entomophathogenic fungi during growing season.

The invasive red swamp crayfish, Procambarus clarkii, is native to southcentral United States and northeastern Mexico. Recently, it has been being spreading in the wild in South Korea. However, its primary sources, introduction routes, establishment, and expansion in South Korea remain unclear. Here, we analyzed genetic diversity and population genetic structures of its domestic natural populations during early invasion, commercial stock from local aquaria (a suspected introduction source), and original United States population using mitochondrial COI gene sequences for 267 individuals and eight microsatellite markers for 158 individuals. Natural and commercial populations of P. clarkii showed reduced genetic diversity (e.g., haplotype diversity and allelic richness). The highest genetic diversity was observed in one original source population based on both genetic markers. Despite a large number of individuals in commercial aquaria, we detected remarkably low genetic diversity and only three haplotypes among 226 individuals, suggesting an inbred population likely originating from a small founder group. Additionally, the low genetic diversity in the natural population indicates a small effective population size during early establishment of P. clarkii in South Korea. Interestingly, genetic differentiation between natural populations and the United States population was lower than that between natural populations and aquarium populations. This suggests that various genetic types from the United States likely have entered different domestic aquariums, leading to distinct natural populations through separate pathways. Results of our study will provide an insight on the level of genetic divergence and population differentiation during the initial stage of invasion of non-indigenous species into new environments.

개미사돈아과의 미기록종인 멧개미사돈(Parapyxidicerus carinatus Sawada, 1964)(신칭)을 한국에서 처음으로 보고하며 이들이 속한 한국 미기록족 Bythinoplectini에 대해 함께 보고한다. 털어잡기 방법으로 세 개체의 표본이 경기와 강원도의 물가에서 확보되었다. 정확한 동정을 위해 외형과 진단형질의 사진 그리고 분포지도를 함께 제공한다.

개미사돈아과의 미기록종인 Philoscotus rostralis Nomura를 한국에 처음으로 보고한다. 정확한 동정을 위해 외형과 진단형질의 사진과 분포 지도를 함께 제공한다.