본 연구는 동해유입하천 (강릉 연곡천, 양양 남대천), 한강수계 (섬강, 속사천), 낙동강수계 (길안천)에 서식하는 참갈겨니 (Zacco koreanus) 개체군을 대상으로 채집된 110개 체로부터 미토콘드리아 DNA COI 유전자 (mitochondrial DNA cytochrome oxidase I)를 분자마커로 이용하여 계통지리학적 분석을 수행하고, 추가적으로 강릉 연곡천 상·중· 하류 개체군을 대상으로 집단유전학적 분석을 수행하였다. 계통지리학 분석 결과, 동해유입하천과 한강수계의 참갈겨니 개체군은 동일한 단일계통을 나타내었고, 낙동강수계의 개체군은 상이한 계통으로 분기됨을 나타내었으며, 다른 수계 계통과의 유전적 거리 수치 범위가 평균 4.0% (3.7~4.2%)로서 동일종 이상 수준을 보여 잠재종 가능성을 시사하였다. 참갈겨니가 서식하는 수계에 따른 형태학적 차이는 연구된 바 있으나 DNA 염기서열의 변이를 이용한 분자유전학적 연구는 부족한 실정이므로 본 연구 결과는 향후 낙동강수계 참갈겨니 개체군의 계통분류학적 연구에 기초자료로 활용될 수 있을 것으로 판단된다. 추후 집단유전체학 및 생태학적 분석을 통하여 관찰된 낙동강수계 계통이 다른 종, 잠재종 혹은 단순히 큰 수준의 종내 변이를 나타내는지에 대한 추가적인 연구가 필요하다. 강릉 연곡천 상·중·하류에 서식하는 개체군의 집단유전학 분석을 통해 중류의 개체군이 상대적으로 높은 다양성을 나타냈으며 상·중·하류 개체군 간의 유전적 차이는 나타나지 않았다. 이는 상·중·하류 개체군 간 유전자 확산이 원활하게 이루어지고 있음을 의미하며 하천의 개체군 간 연결성을 판단할 수 있는 지표로 활용될 수 있다. 하지만 생태학적 시간 스케일의 연구에 더 적합한 분자마커를 이용한 추후 연구가 필요할 것으로 사료된다.

Bemisia tabaci is a species complex consist of about 40 cryptic species. This species is also a vector of at least 100 begomovirus including Tomato yellow leaf curl virus (TYLCV). TYLCV transmitted by B. tabaci in a circulative propagative manner but its molecular mechanism is remain unclear. We investigate the transcriptional response of B. tabaci MED to TYLCV infection using next generation sequencing (NGS) analysis. In total 16757 differentially expressed genes between viruliferous and non-viruliferous whiteflies were analyzed. Among them 289 transcripts found significant, where 116 up-regulated and 173 down-regulated. Our results reveal the whitefly-TYLCV relationship and provide important molecular information about virus transmission of vector insects.

Lysiphlebus orientalis is previously recorded in 2010, which is a more recently recorded than Lysiphlebia japonica. Host range of Lysiphlebus orientalis range is narrow, while that of Lysiphlebia japonica is very broad. Although two species, Lysiphlebus orientalis and Lysiphlebia japonica, are belonged to different genus, respectively, they are morphologically similar each other, which make us confused. Therefore, we have to identify these two cryptic species using COI DNA barcode. We used the ‘NCBI-BLAST (National center for biotechnology information-Basic Local Alignment Search Tool)’ to perform COI DNA barcode identification, and introduce preliminary results in this presentation.

Bemisia tabaci is a species complex consisting of at least 40 species which are morphologically indistinguishable. Althoughgenetic diversity of B. tabaci have been studied in many countries, its information is lack in Bangladesh. The COI sequencewas determined from 91 samples collected in Bangladesh and the phylogenetic relationship was constructed. Four crypticspecies (Asia I, Asia II-1, Asia II-5 and Asia II-10) were present in different regions. While both Asia I and Asia II-1was widely distributed in all around the country, Asia II-5 was central and southern regions, and Asia II-10 was onlyin the central region. Otherwise, our results showed that Asia II-5 had the highest haplotype and nucleotide diversity.Genetic groups of B. tabaci in Bangladesh were most similar with those of Thailand, Vietnam, Pakistan, China, and Indiabut did not show any aggressive cryptic species such as MED and MEAM-1.

Two cryptic species of the black-tailed bamboo aphid, Takecallis arundicolens (Clarke, 1903), are revealed based on DNA barcoding and nymph morphology. Three species, T. arundicolens, T. sp.1 nov. and T. sp.2 nov. have significant genetic differences ranged from 2-8% but, only subtly differing in their nymph morphology. In this study, molecular analyses and morphological comparisons are presented including species keys for alatoid nymphs.

The brown soft scales, Coccus hesperidum (Linnaeus, 1758) is one of the most widely distributed species in the family Coccidae. Interestingly, this species shows considerable morphological variation depending upon the geography and host plants. Although, Korean populations also exhibit morphological variation between geographical regions, this species have been regarded as one species without intensive studies. In this study, we performed Neighbor joining analysis of combined data set of Cytochrome oxidase subunit I COI, 18S ribosomal RNA 18S rRNA, 28S ribosomal RNA 28S rRNA and Elongation factor I-alpha EFI-α genes for Korean populations of brown soft scales. The result of molecular analysis indicated that there are three distinct populations in Korea. Among three populations, one population is separated from two populations with 9% of molecular divergence. Based on high level of molecular divergence, we propose a cryptic species of C. hesperidum with description and illustrations of morphology.

In terms of aphid species identification, both host plant association and morphological characteristics are crucial factors. However, aphids in the genus Aphis Linnaeus (Hemiptera: Aphididae) often are cryptic in morphology due to their rapid radiation. Moreover, overlapping host plant species can make difficult situation worse. Three cryptic species Aphis gossypii Glover, Aphis glycines Matsumura, and Aphis rhamnicola sp. nov. occur together on the Buckthorn, Rhamnus spp. in the overwintering season in Korea. Due to lacking informative morphological characters and host plant sharing, the new species recently has been recognized as a distinct species. In this study, A. rhamnicola sp. nov. on various host plants was compared with the primary host sharing species, A. gossypii and A. glycines, based on morphological and molecular characteristics. In the results, there were significant genetic differences between three species, despite the high similarities in morphology. Our results provide strong evidence for establishing new species, which seems to be a typical heteroecious species that alternates between only primary host, Rhamnus spp., and various secondary hosts. We describe a new species, A. rhamnicola sp. nov., for apterous and alate vivipara, fundatrix, ovipara, and gynopara, including diagnostic key for host sharing species in genus Aphis.

Cryptic species are hardly distinguished by their morphology but reproductively isolated. To understand the evolution and speciation of cryptic species, differentiations between cryptic species should be studied using multiple approaches including morphological analysis. Two of three species under the genus Loxoblemmus in Korea are morphologically similar and may constitute the cryptic species. We studied the differentiations in morphology, calling songs, and genetic sequences to understand patterns of speciation in these three species. Although L.doenitzi was easily distinguished from the other two species based on morphology, the distributions of the number of file teeth and wing morphology overlapped in L. campestris and L. equestris. However, there were clear differentiations in some calling song characters among three cricket species. The number of pulses in a chirp was two in L.doenitzi and four in L. campestris, but that was greater than or equal to six in L. equestris. The genetic sequence analyses using 16S rRNA and COI barcode revealed that L. doenitzi diverged off earlier from the other two species. Calling songs of L. campestris and L. equestris largely differed in spite of their short divergence time. Our results suggest that the speciation processes may involve differentiation in calling songs in the Loxoblemmus complex.

The genus Loxoblemmus has three speices in Korea: L. doenitzi, L. campestris and L. equestris. Males of L. doenitzi have flat heads and triangular horns on both sides of their frons, whereas males of L. campestris and L. equestris have flat heads and no horns. The latter two species are not clearly distinguished based on morphology and thus may constitute cryptic species. We studied the divergence in morphology, calling songs, and genetic sequences to understand patterns of differentiation of these three species. Distributions of the number of file teeth and wing morphology overlapped in L. campestris and L. equestris. In calling songs, the number of pulses in a chirp was four in L. campestris, but that was greater than or equal to six in L. equestris. The genetic sequence analyses using 16S rRNA and COI barcode revealed that L. doenitzi diverged off earlier from the other two species. Thus, the genetic data were congruent with the calling song data in three Loxoblemmus species. Our results suggest that the speciation processes may be closely related to differentiation in calling songs in the Loxoblemmus complex.