Rivers suffer from multiple stressors acting simultaneously on their biota, but the consequences are poorly quantified at the global scale. We evaluated the biological condition of rivers globally, including the largest proportion of countries from the Global South published to date. We gathered macroinvertebrate‐ and fish‐based assessments from 72,275 and 37,676 sites, respectively, from 64 study regions across six continents and 45 nations. Because assessments were based on differing methods, different systems were consolidated into a 3‐class system: Good, Impaired, or Severely Impaired, following common guidelines. The proportion of sites in each class by study area was calculated and each region was assigned a Köppen‐Geiger climate type, Human Footprint score (addressing landscape alterations), Human Development Index (HDI) score (addressing social welfare), % rivers with good ambient water quality, % protected freshwater key biodiversity areas; and % of forest area net change rate. We found that 50% of macroinvertebrate sites and 42% of fish sites were in Good condition, whereas 21% and 29% were Severely Impaired, respectively. The poorest biological conditions occurred in Arid and Equatorial climates and the best conditions occurred in Snow climates. Severely Impaired conditions were associated (Pearson correlation coefficient) with higher HDI scores, poorer physico‐chemical water quality, and lower proportions of protected freshwater areas. Good biological conditions were associated with good water quality and increased forested areas. It is essential to implement statutory bioassessment programs in Asian, African, and South American countries, and continue them in Oceania, Europe, and North America. There is a need to invest in assessments based on fish, as there is less information globally and fish were strong indicators of degradation. Our study highlights a need to increase the extent and number of protected river catchments, preserve and restore natural forested areas in the catchments, treat wastewater discharges, and improve river connectivity.

The giant water bug, Lethocerus deyrolli, is an endangered wetland insect found throughout East Asia. In 2006, the light-attraction flight of L. deyrolli was studied in Gyodong Island, Korea, using artificial light. The flight of L. deyrolli was observed from early June to late October, and two peaks in the numbers of attracted insects were noted in the middle of June and September. L. deyrolli begins to exhibit flight behaviour at a daily mean air temperature of 15°C and above, but optimal flight temperatures for the insect are between 17°C and 19°C, with a wind speed of less than approximately 1.8 m/sec and a relative humidity of around 80%. The length of daylight did not substantially influence the flight pattern. Daily flight occurred principally between 9 pm and 10:30 pm. L. deyrolli individuals attracted by the artificial light were frequently consumed by magpies or house rats. It appears most probable that artificial lights, such as street lights and tennis court lights, constitute a critical factor in the local extinction of L.deyrolli.

Mitochondrial genomes provide an additional data source for nuclear phylogenomics. Recently, the taxonomic classification of Ophiuroidea was changed dramatically based on a molecular phylogenetic analysis that utilized a huge nuclear dataset of transcriptome and target-capture approaches. However, the mitochondrial genome analysis of Ophiuroidea was not conducted sufficiently in depth to allow comparison with current phylogenetic relationships, especially for the Ophintegrida. In this study, eight mitogenomes were newly reported in Amphilepidida and Ophiacanthida. Phylogenetic analyses were undertaken based on the nucleotide sequences of 13 protein coding genes (PCGs), 22 tRNA, and two rRNA, and the amino acid translated sequences of 13 PCGs. The results of the phylogenetic analysis suggested that the amino acid translated sequences were more useful than the nucleotide sequences for the analysis of higher phylogenetic relationships. The mitochondrial gene order of 13 PCGs and two rRNA in Amphilepidida and Ophiacanthida was relatively conserved. However, more complex gene orders occurred in the phylogeny of Amphilepidida and Ophiacanthida, including 22 tRNA. The results of our study suggest that Ophiuroidea has undergone more complex gene rearrangements than other classes of echinoderms.

The nonbiting midge, Glyptotendipes tokunagai Sasa (Diptera: Chironomidae), is an organism that can be used as a water quality indicator. Development