The subfamily Denticollinae is a taxonomically diverse group in the family Elateridae. Denticollinae includes many morphologically similar species and crop pests, as well as many undescribed species at each local fauna. To construct a rapid and reliable identification system for this subfamily, the effectiveness of molecular species identification was assessed based on 421 cytochrome c oxidase subunit I (COI) sequences of 84 morphologically identified species. Among the 84 morphospecies, molecular species identification of 60 species (71.4%) was consistent with their morphological identifications. Six cryptic and/or pseudocryptic species with large genetic divergence (>5%) were confirmed by their sympatric or allopatric distributions. However, 18 species, including a subspecies, had ambiguous genetic distances and shared overlapping intra- and interspecific genetic distances (range: 2.12%–3.67%) suggesting incomplete lineage sorting, introgression of mitochondrial genome, or affection by endosymbionts, such as Wolbachia infection, between species and simple genetic variation within species. In this study, we propose a conservative threshold of 3.6% for convenient molecular operational taxonomic unit (MOTU) identification in the subfamily Denticollinae based on the results of pairwise genetic distances analyses using neighbor-joining, mothur, Automatic Barcode Gap Discovery analysis, and tree-based species delimitation by Poisson Tree Processes analysis. Using the 3.6% threshold, we identified 87 MOTUs and found 8 MOTUs in the interval between 2.5% to 3.5%. Evaluation of MOTUs identified in this range requires integrative species delimitation, including review of morphological and ecological differences as well as sensitive genetic markers. From this study, we confirmed that COI sequence is useful for reassessing species diversity for polymorphic and polytypic species occurring in sympatric and allopatric distributions, and for a single species having an extensively large habitat.

In the present study, the jewel beetle Chrysochroa fulgidissima was taxonomically reassessed based on molecular analyses of cytochrome c oxidase subunit I (COI) and 16S ribosomal RNA (16S) gene partial sequences, and morphological approaches, excluding the subspecies Chrysochroa fulgidissima adachii. Molecular (three data sets, COI, 16S, and COI + 16S in mtDNA) and morphological (quantitative and qualitative characters) evidence suggested that Ch. fulgidissima consists of four independent species found in seven geographical regions, namely Korea, Japan and Taiwan, China (GuangXi and Hainan) and Vietnam, and Okinawa Island. As a result of the large genetic divergences and subtle morphological differences amongst these populations, we were able to infer that the nominotypical subspecies, Chrysochroa fulgidissima fulgidissima, is divided into three pseudocryptic species that have undergone allopatric speciation events. Thus, we propose that the subspecies Chrysochroa fulgidissima alternans should be upgraded to valid specific status. We also provide a description of two new species, Chrysochroa coreana sp. nov. from Korea, and Chrysochroa pseudofulgidissima sp. nov. from China and Vietnam.

The firefly subgenus Hotaria sensu lato of the genus Luciola currently includes four morphospecies: L. (H.) parvula, L. (H.) unmunsana, L (H.) papariensis, and L. (H.) tsushimana. The latter three are taxonomically controversial based on both morphological and molecular data. We examined the phylogenetic relationships and evolutionary history of the species and related congeners using partial COI gene sequences (DNA barcoding). Our phylogenetic analyses consistently supported the monophyly of Hotaria sensu lato, but did not resolve the generic rank. The two types of L. (H.) parvula in Japan can be considered distinct species that arose by pseudocryptic speciation during the Miocene, with substantial genetic divergence (15.41%). Three morphospecies, L. (H.) unmunsana, L (H.) papariensis, and L. (H.) tsushimana, split into several polyphyletic or paraphyletic groups, forming entangled species groups. They are considered an incipient group that is distinguishable genetically but not morphologically, with evidence for recent allopatric speciation events corresponding to geologic events and sea-level changes during the Pliocene and Pleistocene. Group III of L. (H.) unmunsana collected from the Jeolla region is a new taxon.

Palumbina is a small genus of Gelechiidae that includes species distributed only in the Old World. It was recently assigned to the subfamily Thiotrichinae, but the morphological and molecular studies at the species level have not been extensively conducted. In this study, we focused on the taxonomy of the Chinese Palumbina using morphology and DNA barcoding analysis to confirm the species identification and the relationship among closely related species. In China, three species of this genus were recorded previously. A total of 19 were finally recognized in the present study, including 12 new species: P. magnisigna sp. nov., P. grandiunca sp. nov., P. melanotricha sp. nov., P. atricha sp. nov., P. sigmoides sp. nov., P. acuticula sp. nov., P. rugosa sp. nov., P. sineloba sp. nov., P. spinevalva sp. nov., P. acerosa sp. nov., P. triangularis sp. nov. and P. acinacea sp. nov., and five species that are new records for China: P. chelophora (Meyrick, 1918), P. diplobathra (Meyrick, 1918), P. macrodelta (Meyrick, 1918), P. nesoclera (Meyrick, 1929) and P. operaria (Meyrick, 1918). Three new combinations are proposed: P. operaria (Meyrick, 1918) comb. nov., P. albilustra (Walia et Wadhawan, 2005) comb. nov. and P. shivai (Walia et Wadhawan, 2005) comb. nov., and one new synonymy is established: Thyrsostoma albilustra (Walia et Wadhawan, 2005), syn. nov. of P. oxyprora (Meyrick, 1922). Based on the neighbor-joining analysis of COI gene sequences of 67 exemplar specimens, four clades were well supported with high bootstrap values resulting in four species-groups: the guerinii-group, the grandiunca-group, the macrodelta-group and the nesoclera-group. However, seven species were grouped together in an additional clade with weak support and P. diplobathra and P. chelophora were not clustered with any other species due to the high genetic divergences. Palumbina chelophora showed typical characteristics of the genus morphologically, but it was not embedded within Palumbina as monophyletic from the tree, assuming that the sole use of mitochondrial fragments could not resolve the deeper relationship. Therefore, further investigation is needed to clarify those issues. In this study, the generic diagnosis was reviewed based on previous studies and morphological examination.

Aporia crataegi, an Korean endangered species, was first analyzed for DNA barcode sequences based on 28-year-old dried specimens and compared barcode characters with 36 individuals of ten geographical populations of Eurasia. They were revealed to consist of five different haplotypes. Among them, haplotype I was mostly extensive and high frequency with 75%. The south Korean individuals were confirmed to be belonging to haplotype I and have no genetic isolation on COI gene. By these results, we consider that selection of the identical haplotype from other geographical populations may be a requirement prior to performing for conservation and restoration of the Korean population. We also propose to analyse the additional genetic markers in order to understand a more accurate genetic structures between haplotypes of this species.

We have determined the mitochondrial genome of Reticulitermes kanmonensis Takematsu, 1999. The total length of the R. kanmonensis is 16,484 bp with 66.1% A + T content. It consists of 13 PCGs, 22 tRNA , 2 rRNA genes and an A + T–rich control region. All the protein-coding genes used ATN as start codon. But the stop codons were TAA, TAG, and an incomplete termination codon (T) abutting an adjacent tRNA gene. The A + T–rich control region was 1680 bp in length with 70.4% A + T content.

We have determined the mitochondrial genome of Reticulitermes speratus kyushuensis Morimoto, 1968. The total length of the R. speratus kyushuensis is 15,898 bp with 65.3% A þ T content. It consists of 13 PCGs, 22 tRNA, and 2 rRNA genes and an A þ T-rich control region. All the protein-coding genes used ATN as start codon. But the stop codons were TAA, TAG, and an incomplete termination codon (T) abutting an adjacent tRNA gene. The A þ T-rich control region was 1105 bp in length with 67.8% A þ T content.

The genus Scutellathous Kishii, 1955 is a small group known from Korea, Japan, and Taiwan. We carried out a taxonomic study on the Korean species of Scutellathous for the first time.As the result, S. porrecticollis (Lewis, 1894) is revealed to be commonly distributing in Korea and Japan. Additionally, we found that the previous record of Athous jactatus (Lewis, 1894) from North Korea is misidentification of S. porrecticollis. We herein provide redescription of S. porrecticollis and the result of DNA barcoding of congeners belonging to Scutellathous.