Complete mitochondrial genome of Macromia manchurica Asahina, 1964 (Odonata: Macromiidae).

We describe the first time sequencing and assembly of the complete mitochondrial genome of Macromia manchurica Asahina, 1964 (Odonata; Macromiidae; Macromia). The mitochondrial genome of M. manchurica was found to be 15,560 bp. It contains thirteen protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs), and AT-rich region. The overall base composition of A. japonicus is A-38.6%, C-17.0%, G-12.5%, and T-31.9%. A phylogenetic analysis of 14 species within the order Odonata and order Ephemeroptera suggested that Macromia amphigena is most closely related to M. manchurica.

Complete mitochondrial genome of Appasus japonicus Vuillefroy, 1864 (Hemiptera: Belostomatidae).

We describe the initial sequencing and assembly of the complete mitochondrial genome of Appasus japonicus Vuillefroy, 1864 (Hemiptera; Belostomatidae; Appasus). The mitochondrial genome of A. japonicus was found to be 18,608 bp. It contains thirteen protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs) and an AT-rich region. The overall base composition of A. japonicus is A-41.9%, C-17.5%, G-11.9%, and T-28.7%. A phylogenetic analysis of 21 species within the order Hemiptera suggests that Diplonychus rusticus is most closely related to A. japonicus.

Low genetic diversity, local-scale structure, and distinct genetic integrity of Korean chum salmon (Oncorhynchus keta) at the species range margin suggest a priority for conservation efforts.

Chum salmon (Oncorhynchus keta) is an ecologically and economically important species widely distributed across the North Pacific Ocean. However, the population size of this fishery resource has declined globally. Identifying genetic integrity, diversity and structure, and phylogenetic relationships of wild populations of O. keta over an entire species' range is central for developing its effective conservation and management plans. Nevertheless, chum salmon from the Korean Peninsula, which are comprised of its southwestern range margins, have been overlooked. By using mtDNA control region and 10 microsatellite loci, we here assessed the genetic diversity and structure for 16 populations, including 10 wild and six hatchery populations, encompassing the species entire geographic range in South Korea. The analyses showed that genetic diversity is significantly higher for wild than for hatchery populations. Both marker sets revealed significant genetic differentiation between some local populations. Comparisons of six wild and their respective hatchery populations indicated that allele/haplotype frequencies considerably differ, perhaps due to a strong founder effect and/or homogenizing of hatchery populations for stocking practice. Despite its single admixed gene pool for the Korean chum salmon, some local populations housing their own unique lineages should be accorded with a high priority to safeguard their genetic integrities. The results of our comparative analyses of the Korean population with other North Pacific chum salmons (inhabiting regions of Japan, Russia, and North America) revealed a lower diversity but higher contribution to the overall species-level genetic diversity, and also its unique genetic integrity. These findings advocate for the evolutionary significance of the Korean population for species-level conservation.

Complete mitochondrial genome of large dragonfly (Macromia amphigena).

The complete mitochondrial genome of Macromia amphigena (Odonata; Macromiidae; Macromia) was sequenced and found to be 15,594 bp in length including 37 genes (thirteen protein-coding genes (PCGs), 22 transfer RNAs (tRNAs) and two ribosomal RNAs (rRNAs) and a non-coding region). The overall GC content of the mitochondrial genome for M. amphigena was 28.4%. A phylogenetic analysis conducted for 13 species within the order Odonata suggested that Macromia daimoji is the most closely related to M. amphigena.

Contrasting life histories contribute to divergent patterns of genetic diversity and population connectivity in freshwater sculpin fishes.

BACKGROUND: Life history characteristics are considered important factors influencing the evolutionary processes of natural populations, including the patterns of population genetic structure of a species. The sister species Cottus hangiongensis and C. koreanus are small bottom-dwelling freshwater sculpin fishes from South Korea that display marked life history divergence but are morphologically nearly indistinguishable. Cottus hangiongensis evolved an 'amphidromous' life history with a post-hatching pelagic larval phase. They spawn many small eggs in the low reaches of rivers, and hatched larvae migrate to the sea before returning to grow to maturity in the river mouth. In contrast, C. koreanus evolved a 'fluvial' landlocked type with benthic larvae. They release a smaller number of larger eggs, and the larvae undergo direct development, remaining benthic in the upstream rivers throughout their entire lives. We tested whether there were differences in patterns and levels of within-population genetic diversities and spatial population structure between the two closely related Korean sculpins using mitochondrial DNA control region sequences and seven nuclear microsatellite loci. RESULTS: The combined analyses of both marker sets revealed that C. hangiongensis harboured considerably higher levels of within-population genetic diversities (e.g. haplotype/allelic richness, heterozygosities) than C. koreanus. In contrast, the fluvial sculpin exhibited noticeably more spatial population structure than did the amphidromous sculpin, as suggested by pairwise FST statistics. The finding that C. hangiongensis individuals comprised a single random mating population across the east-flowing river basins in the Korean Peninsula, whereas C. koreanus individuals comprised genetically discrete individual populations, was further supported by an individual-based Bayesian population assignment and also factorial correspondence analyses. CONCLUSIONS: The higher genetic diversity, but lower population structure, of the amphidromous sculpin relative to the fluvial sculpin may have resulted from its greater larval dispersal and also possibly, higher fecundity accompanied by an amphidromous life history. Hence, we conclude that contrasting early life histories - including the presence or absence of the pelagic larval phase - may have led to divergent patterns of within-population genetic diversities and spatial population structure between the sister Cottus species following speciation from a common ancestor of marine sculpin.

Comparative assessment of the adverse outcome of wastewater effluents by integrating oxidative stress and histopathological alterations in endemic fish.

This study evaluated the adverse effect of wastewater effluents on three fish species, Carassius auratus, Zacco platypus, and Zacco koreanus, collected in the Eungcheon, Mihocheon, and Busocheon streams, respectively. Fish gills, liver, and kidneys from the mixing zone (MZ) and sites upstream (US) and downstream (DS) of the MZ were analyzed for oxidative stress responses and histology. Catalase and glutathione S-transferase activity was significantly higher at MZ and DS than from US (p<0.05), indicating induction of antioxidant defense mechanisms. Additionally, degree of tissue changes (DTC) indicated highest histopathological alteration in MZ, followed by DS and US. Integrated biomarker response (IBR) for oxidative stress and histopathological alterations showed higher values consistently for Z. koreanus than other two species. Water temperature, EC, and TN levels seemed to be responsible for the observed biomarker responses. These findings indicate that thermal hot spring effluent discharged into Busocheon steam induced the most significant impact on the cool water species (Z. koreanus). Overall, this study suggests that the IBR index is a very useful tool for monitoring in situ adverse effects of wastewater effluents on fish, particularly for histopathological alterations representing prolonged impact.