A previous studies depicting origin and sequence variability of the species using DNA barcoding region with the samples collected from Korea showed relatively low sequence variability. Thus, additional markers that reveal higher variability were necessitated to scrutinize population structure in connection with dispersal and invasive dynamics among international populations. Therefore, we sequenced two complete mitochondrial genomes (mitogenomes) of M. pruinosa from the two haplotypes occurring in Korea (H1 and H3). Comparison of the two mitogenomes each with 16,312 and 16,314 bp evidenced that one region located in the A+T-rich region to provide higher number of haplotypes (4 vs. 3), sequence divergence (1.636% vs. 0.636%), and variable sites (7 vs. 3) than those of DNA barcoding region from the screening test using 13 representative individuals. This variable region, in concatenation with the currently available DNA barcoding region might be useful for population genetic analysis of worldwide populations including those of Korea. †These authors contributed equally to this paper.

To verify the progenitor of B. mori, we sequenced 14 B. mori strains preserved in Korea and one B. mandarina collected in Korea and conducted phylogenetic analysis of Bombycidae using maximum-likelihood method and concatenated sequences of 13 PCGs and 2 rRNA genes. All B. mori strains, regardless of their origin, formed a strong monophyletic group, with the highest nodal support. This B. mori group was placed as the sister to the two B. mandarina collected each from Korea and Shandong, China with the highest nodal support. Finally, the remaining two B. mandarina, which were collected in Japan were independently placed as the most basal lineage of B. mori and B. mandarina group. These results appear to indicate that an immediate ancestor for the domestic silkworm strains may have been originated from China and Korea.

In this study, we sequenced two complete mitogenomes, belonging to the families Scythrididae (Scythris sinensis Felder & Rogenhofer, 1775) and Coleophoridae (Coleophora therinella Tengström, 1848) firstly in each family. Gelechioidea is one of the controversial lineages of Lepidoptera in its phylogenetic position and number of families. Phylogenetic analyses with concatenated sequences of the 13 PCGs and two RNA genes using the maximum likelihood method, placed Coleophoridae, represented only by C. therinella, as a sister group to the families Depressariidae and Autostichidae, with very low nodal support (7%). Scythrididae represented only by S. sinensis was placed as the sister to the family Stathmopodidae, with relatively high nodal support (86%). As more mitogenome sequences from the extended taxonomic groups are obtained further robust phylogenetic inference will be possible.

The spotted-wing drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), is an economically damaging pest that feeds on most thin-skinned fruits. In this study, we sequenced portions of the mitochondrial (mt) COI and ND4 genes from a total of 195 individuals collected mainly from Korea. A total of 139 haplotypes were obtained from the concatenated COI and ND4 sequences. A dataset combining GenBank sequences with our own data identified a total of 94 worldwide COI haplotypes with a maximum sequence divergence of 5.433% (32 bp). A rough estimate of genetic diversity in each country showed higher diversity in ancestral distributional ranges, but the invasion over Asian countries seems to have been substantial because haplotype diversity was only 2.35-3.97-fold lower in the USA, Canada, and Italy than that in the populations ancestral ranges.

In order to understand evolutionary characteristics of gene rearrangement in Lepidoptera, we collected all available complete mitogenome (mitogenome) sequences registered in GenBank (274 mitogenomes from 44 families in 23 superfamilies as of August 6, 2015). It turned up six rearrangements that differ from the arrangement of ancestral insects, including that of the gelechioid Mesophleps albilinella that we sequenced in this study. The M. albilinella mitogenome has a unique gene arrangement among the Gelechioidea: ARNESF (the underline signifies an inverted gene) at the ND3 and ND5 junction, as opposed to the ARNSEF that is found in ancestral insects. Most of the rearrangements can be explained by the tandem duplication-random loss model, but inversion, which requires recombination, is also found in two cases, including M. albilinella. Excluding the MIQ rearrangement at the A+T-rich region and ND2 junction, which is found in nearly all Ditrysia, most of the remaining rearrangements found in Lepidoptera appear to be independently derived in that they are automorphic at several taxonomic scales. Current mitogenomic data are limited, particularly for congeneric data. Thus, future research focused on congenerics could clarify evolutionary independency at the generic level also.

The spotted-wing drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), originally distributed across a few Asian countries, including South Korea, has invaded North America and Europe, but is absent from Australia. In order to export the South Korean grape cultivar Campbell Early to Australia, its potential to serve as oviposition and development medium for SWD must first be determined. In this study, we determined the oviposition and development potential of SWD on Campbell Early, after elucidating the SWD life cycle and establishing an artificial diet-based mass-culturing system. An investigation of the life cycle under five temperature regimes (16, 19, 22, 25, and 28°C) showed that the durations of the egg, larval, and adult stages were shorten when temperature was increased from 16, 19, 22, 25, and 28°C, but pupal duration was shortest at 25°C and extended again at 28°C. A test of oviposition and development potential of SWD on Campbell Early grape clusters showed oviposition of 30.8 ± 6.8 eggs per cluster of injured grapes and 157.7 ± 16.2 eggs on a culture dish of artificial diet. However, in a similar experiment using uninjured grape clusters, only a single egg was deposited on the grape skin, which soon dried. In light of these results, newly harvested grapes left at vineyards during daily harvests are unlikely to serve as an oviposition and development medium for SWD, as long as the grapes remain uninjured.

The spotted-wing drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), was originally observed in a few Asian countries, but is now found even in North America and Europe. Genetic information on geographic variation and relationship may broaden our understanding of origin and migration. As a first step, in this study, a portion of mitochondrial COI gene was sequenced to understand genetic relationship and diversity in Korea. Sequencing of 104 individuals provided 57 haplotypes, with the maximum sequence divergence of 1.5%, suggesting high haplotype diversity and moderate sequence divergence. Comparison to GenBankregistered D. suzukii haplotypes (possibly from Spain, Portugal, USA) has shown 100% sequence identity to most of the haplotypes found in this study, but two USA sequences were found to be independent haplotypes, with the sequence divergence ranging from 0.5% ~ 1.4% from our samples in the 553-bp comparison. Phylogenetically, no separable group was found, but, population genetically, the only Chinese population, Sandong, was significantly differentiated (p < 0.05) from all Korean populations, without sharing any haplotype. Among 28 pairwise comparisons of Korean populations only two comparisons showed a significant genetic differentiation, indicating that no population in Korea is completely isolated. Geographically, one haplotype (SWDBA06) was relatively widespread (five among nine localities) and a few haplotypes were found in more than one locality, but most haplotypes were restricted in a locality as a single individual. Overall, high rate of per generation female migration (Nm = 0.75 ~ infinite) and low level of geographic separation (FST=0~0.40) among localities were characteristic. Current data is limited mainly to Korean localities, thus, an expanded study may provide further scrutinized analysis for the fly.

We newly sequenced mitogenomes of five skippers belonging to Lepidoptera to obtain further insight into characteristics of butterfly mitogenomes and performed phylogenetic reconstruction using all available gene sequences (PCGs, rRNAs, and tRNAs) from 85 species in 19 families in eight superfamilies. The general genomic features found in the butterflies also were found in the five skippers: a high A/T composition (79.3% - 80.9%), dominant usage of TAA stop codon, similar skewness pattern in various levels, consistently long intergenic spacer sequence between tRNAGln - ND2 (64-87 bp), the ATACTAA motif betweent RNASer(UCN) and ND1, and characteristic features of the A+T-rich region (the motif ATAGA, varying length of poly-T stretch, and poly-A stretch). The start codon for COI was CGA in four skippers as typical, but Lobocla bifasciatus evidently possessed canonical ATG as start codon. Phylogenetic analyses mainly yielded the consensus superfamilial relationships ((((((Bombycoidea + Noctuoidea + Geometroidea) + Pyraloidea) + Papilionoidea) + Tortricoidea) + Yponomeutoidea) + Hepialoidea) with a high support for most nodes, confirming the validity of Macroheterocera and its sister relationship to Pyraloidea. Within Rhopalocera the familial relationships (Papilionidae + (Hesperiidae + (Pieridae + ((Lycaenidae + Riodinidae) + Nymphalidae))) were strongly supported, confirming invalidity of the superfamily Hesperioidea. On the other hand, superfamilial relationships among Noctuoidea, Geometroidea, and Bombycoidea and the familial relationships among Saturniidae, Sphingidae, and Bombycidae were dubious, requiring further representative taxon sampling.