Transcriptome profiling for developmental stages Protaetia brevitarsis seulensis with focus on wing development and metamorphosis.

A white-spotted flower chafer Protaetia brevitarsis seulensis widely distributed in Asian countries is traditionally used in oriental medicine. This study explored gene expression abundance with respect to wing development and metamorphosis in P. b. seulensis based on the large-scale RNA-seq data. The transcriptome assembly consists of 23,551 high-quality transcripts which are approximately 96.7% covered. We found 265 wing development genes, 19 metamorphosis genes, and 1,314 candidates. Of the 1,598 genes, 1,594 are included exclusively in cluster 4 with similar gene co-expression patterns. The network centrality analyses showed that wing development- and metamorphosis-related genes have a high degree of betweenness centrality and are expressed most highly in eggs, moderately in pupa and adults, and lowest in larva. This study provides some meaningful clues for elucidating the genetic modulation mechanism of wing development and metamorphosis in P. b. seulensis.

Possible species discrimination of a blotched nerite Nerita albicilla with their distribution pattern and demographic history in the Indo-Pacific.

The blotched nerite Nerita albicilla (Linnaeus 1758) is distributed in intertidal areas of the Indo-Pacific. In South Korea, it has been found only in the southernmost region of Jeju Island so far. Owing to its limited distribution, it can be a promising intertidal species helpful for monitoring global climate change effects in the Korean Peninsula. We performed population genetic analyses based on 393 COI haplotypes from 697 N. albicilla, including 167 from this study and 530 from public databases. The results showed that there are two distinct genetic lineages in N. albicilla: PAIO (Palearctic, Australasia, Indo-Malay, and Oceania) and Afrotropic lineages. DNA barcoding gap analyses indicated that the two lineages could be differentiated into two different species: N. albicilla (PAIO) and N. originalis sp. nov. (Afrotropic) (3.96%). Additionally, it was revealed that their divergence time was ca. 5.96 Ma and dramatic diversification of COI haplotypes occurred during the late Pliocene and Pleistocene. The results of MDA, BSP, and neutrality test implied recent population size expansion, which was estimated to be ca. 250 Ka. Finally, we discussed whether the observation of N. originalis sp. nov. in South Korea is due to the northward migration through ocean currents caused by global warming or due to artificial activity through marine transportation.

The complete mitochondrial genome of the woodwasp Euxiphydria potanini (Hymenoptera, Xiphydrioidea) and phylogenetic implications for symphytans.

The long-necked woodwasp superfamily Xiphydrioidea belongs to the suborder Symphyta (Hymenoptera). Here we newly characterize the complete mitochondrial genome of the South Korean Euxiphydria potanini (Xiphydriidae) using next-generation sequencing: 16,500 bp long with 84.27% A + T content and 37 typical mitochondrial genes including those encoding 13 PCGs, 2 rRNAs, 22 tRNAs, and one A + T rich region. We compare the patterns of symphytan mitochondrial gene arrangement with those of an ancestral insect form and found some synapomorphic rearrangements in phylogenetic context. We use a variety of nucleotide and amino acid sequence alignments (thirteen mtPCGs and/or eight nDNAs) alongside step-by-step exclusions of long-branched taxa to elucidate the phylogenetic position of Xiphydrioidea and phylogenetic relationships among the seven symphytan superfamilies, except for Anaxyeloidea of which no mtgenome was available. The monophyly of symphytan superfamilies (with weak support for Pamphilioidea), sister-group relationship of Xiphydrioidea and Cephoidea, and Symphyta being paraphyletic to Apocrita, etc. are consistently supported by maximum likelihood and Bayesian inference trees. We also discuss the problematic phylogenetic positions of Orussoidea and Siricoidea and propose a hypothetical scenario of morphological character transition during hymenopteran evolution based on morphological key characteristics, such as the cenchrus and the wasp-waist.

Complete mitochondrial genome of a malaria vector mosquito Anopheles sinensis from South Korea.

We present the complete mitochondrial genome of a Malaria vector Mosquito Anopheles sinensis Wiedemann, 1828 from South Korea. The mitochondrial genome is about 15,421 bp long and contains 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an A-T rich region. The present data were compared with those from China with respect to PCG sequence differences, tRNA structure, gene order, and control region (CR) structure. An. sinensis mitochondrial genomes from northeast Asia share identical gene composition and gene order. In contrast, they have distinct differences in the CR within the range 8.75% (51/583 bp) to 9.95% (58/583 bp). The phylogenetic analysis showed that An. sinensis from South Korea was clustered together with those from China, but there existed distinct genetic distance between the two. Likewise, mitochondrial genome sequences from other Anopheles species were employed to infer phylogenetic relationships among the members of the genus Anopheles. This study further promotes the enrichment of An. sinensis mitochondrial genome data, providing useful information for their mitochondrial genetic differences along with geographical distances in northeast Asia.

Liolophura species discrimination with geographical distribution patterns and their divergence and expansion history on the northwestern Pacific coast.

The chiton Liolophura japonica (Lischke 1873) is distributed in intertidal areas of the northwestern Pacific. Using COI and 16S rRNA, we found three genetic lineages, suggesting separation into three different species. Population genetic analyses, the two distinct COI barcoding gaps albeit one barcoding gap in the 16S rRNA, and phylogenetic relationships with a congeneric species supported this finding. We described L. koreana, sp. nov. over ca. 33°24' N (JJ), and L. sinensis, sp. nov. around ca. 27°02'-28°00' N (ZJ). We confirmed that these can be morphologically distinguished by lateral and dorsal black spots on the tegmentum and the shape of spicules on the perinotum. We also discuss species divergence during the Plio-Pleistocene, demographic expansions following the last interglacial age in the Pleistocene, and augmentation of COI haplotype diversity during the Pleistocene. Our study sheds light on the potential for COI in examining marine invertebrate species discrimination and distribution in the northwestern Pacific.

Characterization of metapopulation of Ellobium chinense through Pleistocene expansions and four covariate COI guanine-hotspots linked to G-quadruplex conformation.

The land snail Ellobium chinense (L. Pfeiffer, 1855) (Eupulmonata, Ellobiida, Ellobiidae), which inhabits the salt marshes along the coastal areas of northwestern Pacific, is an endangered species on the IUCN Red List. Over recent decades, the population size of E. chinense has consistently decreased due to environmental interference caused by natural disasters and human activities. Here, we provide the first assessment of the genetic diversity and population genetic structures of northwestern Pacific E. chinense. The results analyzed with COI and microsatellites revealed that E. chinense population exhibit metapopulation characteristics, retaining under the influence of the Kuroshio warm currents through expansion of the Late-Middle and Late Pleistocene. We also found four phylogenetic groups, regardless of geographical distributions, which were easily distinguishable by four unidirectional and stepwise adenine-to-guanine transitions in COI (sites 207-282-354-420: A-A-A-A, A-A-G-A, G-A-G-A, and G-G-G-G). Additionally, the four COI hotspots were robustly connected with a high degree of covariance between them. We discuss the role of these covariate guanines which link to form four consecutive G-quadruplexes, and their possible beneficial effects under positive selection pressure.

The mitochondrial genome of a giant water bug Lethocerus deyrollei (Hemiptera: Belostomatidae) from South Korea.

A giant water bug Lethocerus deyrollei (Hemiptera: Belostomatidae) is a large, predatory, and nocturnal hemipteran insect, which has been considered threatened and thus enrolled as an endangered species in South Korea and Japan. Here, we characterized the complete mitochondrial genome of L. deyrollei, which has a circular form with 19,295 bp in length, which is the longest when compared to those of the 111 hemipteran species reported so far. Its longest genome size is due to the extremely extended CR (4686 bp), which is much longer than those of China and Japan. It consisted of a total of 37 genes (13 PCGs, 22 tRNA genes, and two rRNA genes) and one control region (CR). The genome composition and gene order were identical to those previously reported from the same species of China and Japan with over 99.7% sequence similarities except for CR and trnI. The nucleotide composition was highly A + T biased, accounting for 71% of the whole mitochondrial genome, as in other species of Nepoidea. Based on the aa sequences of 13 PCGs, we reconstructed a maximum likelihood tree, which indicated that the three mitochondrial genomes of L. deyrollei from South Korea, China, and Japan are grouped, and also Lethocerus, Belostomatidae, Nepoidea, Nepomorpha, Heteroptra are strong monophyletic groups, respectively.

The complete mitochondrial genome of the two-spotted cricket Gryllus bimaculatus (Orthoptera: Gryllidae) from South Korea.

The complete mitochondrial genome of a two-spotted cricket Gryllus bimaculatus (Orthoptera: Gryllidae) from South Korea is determined and characterized in this study. The circular genome is 16,075 bp long, which consists of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA genes, and an A + T-rich region. It has a base composition of A (40.35%), G (9.09%), C (16.80%), and T (33.76%). The gene order is identical to the ancestral gene arrangement pattern generally shown in arthropods, with the exception of an inversion of trnN-trnS1-trnE into trnE-trnS1-trnN. The maximum likelihood (ML) tree supports that G. bimaculatus is a distinct member of the monophyletic family Gryllidae.

Complete mitochondrial genome of a hen harrier Circus cyaneus (Accipitriformes: Accipitridae) from South Korea.

A hen harrier Circus cyaneus (Accipitriformes: Accipitridae), a migrant raptor having a wide breeding range from Europe to Northeast Asia, migrates to more southerly areas (Southern Europe, China, Korea and Japan) in winter. In this study, the complete mitochondrial genome of C. cyaneus was completely sequenced and characterized. It was 20,173 bp in length being composed of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and two control regions. It has a base composition of A (32.2%), G (12.6%), C (30.5%) and T (24.7%). The phylogenetic tree reconstructed based on the maximum likelihood (ML) method confirms that C. cyaneus places within the clade of the family Accipitridae in the monophyletic avian order Accipitriformes.

Review of the family Proctorenyxidae (Hymenoptera: Proctotrupoidea), with description of new species from South Korea.

Kozlov (1994) established a new parasitic proctotrupoid family, Renyxidae, for a single species, Renyxa incredibilis, from Primorskij Krai, in the Russian Far East. A new genus and species, Hsiufuropronia chaoi, was described from China, Beijing (Yang 1997) in the family Roproniidae. Lelej and Kozlov (1999) noticed that Renyxa was preoccupied and was initially used by Kurochkin and Slankis (1973) for a genus of flatworms (Cestoda: Litobothridae). According to Articles 39, 60 of the Code (ICZN 1999), the names of the genus and family were changed to Proctorenyxa Lelej & Kozlov, 1999 (Lelej & Kozlov 1999). He et al. (2002) transferred Hsiufuropronia from Roproniidae to Proctorenyxidae based on Yang's original description and illustrations, and synonymized Hsiufuropronia Yang under Proctorenyxa Lelej & Kozlov. Later, He and Xu (2015) proposed that the family name Proctorenyxidae should be replaced by Hsiufuroproniidae and the genera Proctonenyxa Lelej & Kozlov and Hsiufuropronia Yang should be separate. However, the replacement name Hsiufuroproniidae contradicts article 39 of the Code (ICZN 1999).