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Every summer and fall, Japanese children (mostly boys) spend hours catching and playing with insects, or mushi. Different species are associated with the seasons, times of the day, or specific games. Mushi customs are centuries old, were traditionally passed from grandfather to grandchild, and are reflected in electronic and "virtual" animals that mimic mushi and in the Pokemon craze. (SV)

Spodoptera frugiperda, an invasive pest insect that targets maize and other crops, first arrived in Japan in the summer of 2019. This species occurs year‐round in East Asian subtropical regions such as southern mainland China and the island of Taiwan, where the mean air temperature in the coldest month is above 10°C. Adults are similarly found throughout the year on the southwestern islands of Japan. Trap monitoring there showed continuous or intermittent S. frugiperda catches in the three winter seasons since 2019. However, it was difficult to distinguish between immigrants arriving from these neighbouring areas and local individuals occurring on each Japanese island. In this study, the possible natal origin of captured insects on five small islands (Yonagunijima, Taramajima, Okinawajima, Amamioshima and Tanegashima) was determined by investigating the strontium radiogenic isotope ratios (87Sr/86Sr) and comparing them with those of reference hosts and insects. Since trapping data and the 87Sr/86Sr values of trapped insects didn't support S. frugiperda's winter breeding on the northernmost island, Tanegashima, further analysis was limited to the four southern islands. The 87Sr/86Sr values of reference host plants and reared insects on the four islands ranged from 0.70929 to 0.71009, while those of catch insects ranged from 0.70885 to 0.71090. The 87Sr/86Sr values of the catch insects and the reference on the four islands did not differ significantly. In addition, the monthly averages of daily mean air temperature in January and February 2020–2022 were above 10°C, and the wind direction at the surface was mostly from the northeast or northwest. These pieces of evidence, together with winter host availability, suggested that S. frugiperda occurs year‐round on the islands. In other words, the year‐round occurrence area of S. frugiperda in East Asia extends to the Japanese southwestern islands below Amamioshima Island. [ABSTRACT FROM AUTHOR]

Pear pollination is performed by artificial pollination because the pollination rate through insect pollination is not stable. Pollen must be collected to secure sufficient pollen for artificial pollination. However, recently, collecting sufficient amounts of pollen in Japan has become difficult, resulting in increased imports from overseas. To solve this problem, improving the efficiency of pollen collection and strengthening the domestic supply and demand system is necessary. In this study, we proposed an Artificial Intelligence (AI)-based method to estimate the amount of pear pollen. The proposed method used a deep learning-based object detection algorithm, You Only Look Once (YOLO), to classify and detect flower shapes in five stages, from bud to flowering, and to estimate the pollen amount. In this study, the performance of the proposed method was discussed by analyzing the accuracy and error of classification for multiple flower varieties. Although this study only discussed the performance of estimating the amount of pollen collected, in the future, we aim to establish a technique for estimating the time of maximum pollen collection using the method proposed in this study. [ABSTRACT FROM AUTHOR]

The polymitarcyid mayfly Ephoron shigae (Takahashi, 1924) generally propagates via sexual reproduction, but a parthenogenetic-dominant monophyletic strain derived from western Japanese sexual-dominant strains is widely distributed in Japan. This species may provide a case study on distribution patterns of genetic divergence in sexual-dominant and parthenogenetic-dominant strains of aquatic insects. In this study, we sought to characterize the distribution of parthenogenetic-dominant and sexual-dominant strains of E. shigae in eastern Japan and to assess whether there was sex ratio bias among local populations with and without the parthenogenetic strain, as well as the parthenogenetic reproductive success of both strains. We found that in eastern Japan, the parthenogenetic-dominant strain with the cytochrome c subunit I haplotype C1 is more widespread than sexual-dominant strains and that there are sites where both parthenogenetic-dominant and sexual-dominant strains coexist. There was no sex ratio bias at sites where the parthenogenetic-dominant strain was not observed, but at sites with both reproductive strains, the sex ratio was skewed toward females (64–99%), though the degree of bias depended on the relative frequency of the 2 strains. We found no evidence that females of the parthenogenetic-dominant strain mated after emergence; thus, in eastern Japan, females of the parthenogenetic-dominant strain may not mate even when males are present, and they pass through generations by parthenogenesis. The success rates of unfertilized oocytes of the parthenogenetic-dominant strain varied, with developmental success rates of 70% or higher. Oocyte batches with extremely low success rates (<10%) were also observed at 2 of the sites with both strains. Embryo developmental success of unfertilized oocytes in sexual-dominant strains was generally low (<30%), but exceptionally high rates of >90% were observed. At sites with both strains, the degree of developmental success of unfertilized oocytes in the parthenogenetic-dominant strain may be related to its relative frequency. Examining the causes of the distribution of these strains, and how they may change in the future, will provide new perspectives on reproductive modes and geographic parthenogenesis. [ABSTRACT FROM AUTHOR]

The genus Brentiscerus Scudder, 1962 (Hemiptera, Heteroptera, Lygaeoidea, Rhyparochromidae, Drymini) is widely distributed in the Australian Region; however, no species have been recorded in the Palaearctic Region. Here, we report Brentiscerus putoni (White, 1878) from Japan, based on materials collected from Honshu, Kyushu, and Kamikoshiki-shima Island. This discovery represents the first Palaearctic record of the genus and suggests that B. putoni may be an alien species in Japan. All 25 specimens were collected in a well-investigated region of Japan since 2013. [ABSTRACT FROM AUTHOR]

Rice fields are characterized by high algal production and dense mats of filamentous green algae, and they function as habitats for various aquatic organisms. However, how algal production supports the secondary production of aquatic consumers in rice fields has not been assessed. Herein, aquatic food web structures in two adjacent rice fields in northeastern Japan were examined using carbon and nitrogen stable isotope analyses. Filamentous algae often showed higher δ13C values (mean, −23.1‰ to −21.4‰) than other organic matter sources, including particulate organic matter, benthic microalgae, and soil organic matter (−30.1‰ to −25.4‰). A δ13C‐based isotopic mixing model estimated that among 19 taxa of herbivores and omnivores, most taxa depended on filamentous algae‐derived carbon (ca. >30%). Particularly, Peltodytes intermedius larvae, a specialist feeder for filamentous algae, showed the highest reliance (mean, 66.7%–80.0%). The microcrustacean, Ostracoda sp. also utilized a diet consisting of a substantial proportion of filamentous algae‐derived carbon (57.6%). Seven out of 10 carnivorous taxa showed reliance on filamentous algae‐derived carbon by >30%. Particularly, larvae of beetles (Berosus sp., Enochrus sp., and Hydrochara affinis) showed the highest reliance (40.2%–44.3%). They could assimilate filamentous algae‐based carbon by consuming herbivores, such as P. intermedius. Because fresh filamentous green algae were eaten less by aquatic consumers, the herbivores could consume decomposed filamentous algae rather than fresh ones. Our results suggest that filamentous algae are one of the major organic matter sources supporting secondary production in rice field food webs. [ABSTRACT FROM AUTHOR]

When gene flow has been restricted between populations, the genetic structure of such species often reflects geohistory and climate changes. Populations of species inhabiting high-altitude regions, known as 'Sky Islands', are isolated and exhibit restricted gene flow, so they often have habitat-specific genetic structures that correspond to their surrounding geographical structures. Here we focus on a limnephilid caddisfly, Rivulophilus sakaii , which inhabits the alpine zone of Japan. Phylogenetic analyses were conducted based on the mtDNA COI and 16S rRNA regions, and the nDNA 18S rRNA, 28S rRNA, CAD , EF1-α , and POL-II regions; the results indicated three phylogeographically differentiated intraspecific lineages. Haplotype network and demographic analyses based on the mtDNA COI region suggested the size of the respective isolated populations has stabilized. This suggests that mountain formation in the Japanese Archipelago due to volcanic activity has resulted in barriers to migration and dispersal between high-altitude aquatic insect populations. This was inferred to be an effect of Quaternary climate changes that caused vertical distributional shifts following mountain formation, resulting in repeated connection and fragmentation of the populations. This is important supporting information with regard to discussing the effects and functions of geohistory and climatic changes on the phylogenetic evolution of organisms presently inhabiting interglacial 'Sky Islands'. [ABSTRACT FROM AUTHOR]

Many native insects have evolved defenses against native predators. However, their defenses may not protect them from non-native predators due to a limited shared history. The American bullfrog, Aquarana catesbeiana (Anura: Ranidae), which has been intentionally introduced to many countries, is believed to impact native aquatic animals through direct predation. Adults of whirligig beetles (Coleoptera: Gyrinidae), known for swimming and foraging on the water surface of ponds and streams, reportedly possess chemical defenses against aquatic predators, such as fish. Although whirligig beetles potentially encounter both bullfrogs and other frogs in ponds and lakes, the effectiveness of their defenses against frogs has been rarely studied. To assess whether whirligig beetles can defend against native and non-native frogs, we observed the behavioral responses of the native pond frog, Pelophylax nigromaculatus (Anura: Ranidae), and the invasive non-native bullfrog, A. catesbeiana, to native whirligig beetles, Gyrinus japonicus and Dineutus orientalis, in Japan. Adults of whirligig beetles were provided to frogs under laboratory conditions. Forty percent of G. japonicus and D.orientalis were rejected by P. nigromaculatus, while all whirligig beetles were easily consumed by A. catesbeiana. Chemical and other secondary defenses ofG. japonicus and D. orientalis were effective for some individuals of P. nigromaculatus but not for any individuals of A. catesbeiana. These results suggest that native whirligig beetles suffer predation by invasive non-native bullfrogs in local ponds and lakes in Japan. [ABSTRACT FROM AUTHOR]

Across Japan, populations of Sika deer (Cervus nippon) have grown rapidly over recent decades, and Odaigahara has particularly high densities of Sika deer. In Odaigahara, this overpopulation has led to changes in stream flow and riparian landscapes, with formerly diverse communities of dwarf bamboo growing increasingly homogenous. Lower-layer vegetation (Sasamorpha borealis, Sasa nipponica, bryophytes) that had covered Odaigahara disappeared, the number of trees of higher-layer vegetation decreased, and the landscape changed from a humid, dense landscape to a bright, homogenous landscape. Vegetation plays an important role in the succession of benthic invertebrates in streams. In this study, we examined changes in the benthic invertebrate assemblages of Odaigahara and related them to vegetation history. In 2006, there were fewer individuals and genera of benthic invertebrates than in 1983. Benthic invertebrate composition also differed from 1983 and the degree of difference varied by stream basin. The abundance of Ephemeroptera (e.g. Drunella spp.) was decreased and of Plecoptera (e.g. Sweltsa spp.) was increased. Over the same period, lower-layer vegetation and humidity decreased while temperature increased; these factors also likely contribute to the observed changes to benthic invertebrate assemblages. Implications for conservation: The forests of Odaigahara are still subject to complex factors such as sika deer, human activities and global environmental changes. Comparison of current and historical benthic invertebrate communities will help to identify the restoration goals for the forest ecosystems necessary for benthic invertebrate communities. Proper management of deer and conservation of remnant vegetation, including rhizomes, in the Odaigahara will contribute to the maintenance of the present and future benthic invertebrate community. [ABSTRACT FROM AUTHOR]

The red-necked longhorn beetle, Aromia bungii, is an invasive wood-boring insect that has recently invaded Europe and Japan, seriously damaging stone fruit trees in both native and invaded regions. Rose oxide, including both cis- and trans-isomers, was previously found in the volatiles produced by A. bungii adults, while the inter- and intra-specific behavioral functions of this compound remain unclear. By manually shaking the beetles, a much greater amount of rose oxide was released from the beetles, compared to that released from nondisturbed beetles. Rose oxide was further determined to be original from a white-colored secretion which was immediately sprayed by the beetles that were hand captured or squeezed by tweezers. These findings indicate that this pungent compound putatively has a role as an allomone component released from the defensive secretion by A. bungii adults when threatened, which may be an adaptive defensive strategy against the predation of natural enemies such as insectivorous birds. Y-tube olfactory assays revealed that rose oxide, at a high concentration, was significantly repellent to both sexes of A. bungii adults, suggesting that rose oxide may also have a function in the intraspecific communication of A. bungii. Considering the low price of the commercially available products, this repellent effect of rose oxide may facilitate the development of novel control strategies, such as push–pull strategy, for A. bungii. [ABSTRACT FROM AUTHOR]

Many wetland plants rely on insects for pollination. However, studies examining pollinator communities in wetlands remain limited. Some studies conducted in large wetlands (> 10 ha) have suggested that wetland-dependent flies, which spend their larval stage in aquatic and semi-aquatic habitats, dominate as pollinators. However, smaller wetlands surrounded by secondary forests are more prevalent in Japan, in which pollinators from the surrounding environment might be important. Additionally, information regarding floral traits that attract specific pollinator groups in wetland communities is scarce. Therefore, this study aimed to understand the characteristics of insect pollinators in a small natural wetland (2.5 ha) in Japan. We examined the major pollinator groups visiting 34 plant species and explored the relationship between the flower visitation frequency of each pollinator group and floral traits. Overall, flies were the most dominant pollinators (42%), followed by bees and wasps (33%). Cluster analysis indicated that fly-dominated plants were the most abundant among 14 of the 34 target plant species. However, 85% of the hoverflies, the most abundant flies, and 82% of the bees were non-wetland-dependent species, suggesting that these terrestrial species likely originated from the surrounding environment. Therefore, pollinators from the surrounding environment would be important in small natural wetlands. Flies tend to visit open and white/yellow flowers, whereas bees tended to visit tube-shaped flowers, as in forest and grassland ecosystems. The dominance of flies in small wetlands would be due to the dominance of flowers preferred by flies (e.g., yellow/white flowers) rather than because of their larval habitats. [ABSTRACT FROM AUTHOR]

Simple Summary: This publication describes a new Lachninae aphid genus and species (Insecta, Hemiptera: Aphididae)—Miyalachnus—from Japan. This genus is characterized by unique and outstanding morphological features on the legs and antennae and can be easily recognized within the remaining Lachninae genera. We provided a detailed scanning electron microscopy study on the general morphology and sensilla of the viviparous and sexual generations. We presented the biology of the genus with descriptions of all available morphs. The tribe Tuberolachnini within the Lachninae (Hemiptera: Aphididae) is particularly intriguing due to its morphological traits and various ecological associations. Among the genera within this group, Pyrolachnus stands out as relatively understudied. Currently, only one species, Pyrolachnus imbricatus nipponicus Sorin, 2011, is known from Japan, distinguished by its distinctive characteristics. Through meticulous morphological analyses, we introduce a novel Lachninae genus, Miyalachnus gen. nov., associated with Cerasus and Prunus spp. (Rosaceae) in Japan. This new genus accommodates P. imbricatus nipponicus, now recognized as Miyalachnus nipponicus (Sorin, 2011) comb. nov. Additionally, we present a second species within this genus, Miyalachnus sorini sp. nov., along with comprehensive SEM morphological examination and insights into its biology. Our study describes in detail the morphological characteristics of both viviparous and bisexual generations of Miyalachnus, as well as their relationships with related genera. [ABSTRACT FROM AUTHOR]

The giant water bug Kirkaldyia deyrolli is one of the most well‐known endangered aquatic insects in Japan. The population of this species in Kyushu, one of the four major islands of the Japanese Archipelago, is extremely limited. In the present study, we identified a new population of K. deyrolli and undertook population genetic structure analyses based on genome‐wide nuclear DNA single nucleotide polymorphisms (SNPs). We collected samples using a nonlethal sampling method and obtained 59,279 SNPs. The results of our study confirm that sufficient SNP data for population genetic structure analysis can be obtained through nonlethal sampling. We determined that the newly identified population is genetically differentiated from a previously identified population on Kyushu. Therefore, this population is considered highly important for the conservation of K. deyrolli in Kyushu. [ABSTRACT FROM AUTHOR]

Irradiation is widely used worldwide to sterilize and kill insects in food, and prevent the germination of agricultural products. However, in Japan, food irradiation is prohibited except to prevent potato sprouting. Herein, 5,6-dihydrothymidine （DHdThd） residue̶a damaged nucleoside generated from the thymidine （dThd） residue in DNA contained in food upon irradiation̶was used as a detection indicator. Eight dried plant-based food samples were gamma ray-irradiated in the range from 3.2 to 8.3 kGy. Subsequently, DNA was extracted from the irradiated sample and digested into nucleosides by the three enzymes, and the test solution was analyzed by liquid chromatography tandem mass spectrometry （LC-MS/MS）. Evidently, in all samples, the concentration ratio of DHdThd to dThd in the test solution （DHdThd/dThd） was dependent on the irradiation dose; moreover, during storage under frozen conditions for at least 890 d post-irradiation, this concentration ratio was equal to that immediately after irradiation. The irradiation histories of the eight types of dried plant-based food samples were correctly detected. [ABSTRACT FROM AUTHOR]

Many insects are associated with endosymbionts that influence the feeding, reproduction, and distribution of their hosts. Although the small green mirid, Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), a zoophytophagous predator that feeds on plants as well as arthropods, is a globally important biological control agent, its microbiome has not been sufficiently studied. In the present study, we assessed the microbiome variation in 96 N. tenuis individuals from 14 locations throughout Japan, based on amplicon sequencing of the 16S ribosomal RNA gene. Nine major bacteria associated with N. tenuis were identified: Rickettsia, two strains of Wolbachia, Spiroplasma, Providencia, Serratia, Pseudochrobactrum, Lactococcus, and Stenotrophomonas. Additionally, a diagnostic PCR analysis for three typical insect reproductive manipulators, Rickettsia, Wolbachia, and Spiroplasma, was performed on a larger sample size (n = 360) of N. tenuis individuals; the most prevalent symbiont was Rickettsia (69.7%), followed by Wolbachia (39.2%) and Spiroplasma (6.1%). Although some symbionts were co-infected, their prevalence did not exhibit any specific tendency, such as a high frequency in specific infection combinations. The infection frequency of Rickettsia was significantly correlated with latitude and temperature, while that of Wolbachia and Spiroplasma was significantly correlated with host plants. The predominance of these bacteria and the absence of obligate symbionts suggested that the N. tenuis microbiome is typical for predatory arthropods rather than sap-feeding insects. Rickettsia and Wolbachia were vertically transmitted rather than horizontally transmitted from the prey. The functional validation of each symbiont would be warranted to develop N. tenuis as a biological control agent. [ABSTRACT FROM AUTHOR]

The monotypic genus Enigmadiplosis Harris (Diptera: Cecidomyiidae) was placed in the tribe Clinodiplosini based on adult morphology, but the genus is somewhat puzzling because larvae are typical for the tribe Cecidomyiini. In this study, we describe Enigmadiplosis harrisi sp. nov., a pest species that damages young leaves of the ornamental shrub Rhododendron pulchrum in Mie Prefecture, Honshu, Japan. We also conducted a molecular phylogenetic analysis to confirm the tribal placement. The result clearly indicates that Enigmadiplosis belongs to Cecidomyiini and we therefore assign the genus to that tribe. In addition, we redescribe Clinodiplosis rhododendri (Felt) that forms leaf-roll galls on Rhododendron spp. in eastern North America to allay future questions as to the identity and show that this is unrelated to the new Japanese species. [ABSTRACT FROM AUTHOR]

Background: Edible insects may contain arsenic. Analysis of arsenic species is necessary in order to accurately assess arsenic exposure. Objective: An analytical method was validated and used to determine and quantitate arsenic species in edible insects. Methods: Arsenic species were extracted from edible insects by heating at 100°C in 0.3 mol/L nitric acid. The concentration of arsenic species was then determined by LC-inductively coupled plasma-mass spectrometry (LC-ICP-MS) using an octadecylsilane (ODS) column with a mobile phase containing an ion-pair reagent. Results: The LOD (0.007-0.012 mg/kg), LOQ (0.021-0.038 mg/kg), repeatability (1.2-3.2%), intermediate precision (2.8-4.5%), and trueness (recoveries 97-102% based on spiked samples) of the proposed method were satisfactory for inorganic arsenic, dimethylarsinic acid (DMA), and arsenobetaine (AB) in edible insects. Total arsenic was detected in all samples obtained in Japan (Asian forest scorpion, diving beetles, giant water bug, grasshoppers, June beetles, mole crickets, male rhino beetle, female rhino beetle, sago worms, and silkworm pupae) and consisted of mostly inorganic arsenic. Beetles in particular showed relatively high levels. Conclusion: Arsenic content varies among edible insect species. Feed control is important, as arsenic concentrations in edible insects may be feed dependent. Highlights: Arsenic species in edible insects were analyzed by LC-ICP-MS using an ODS column with a mobile phase containing an ion-pair reagent. Inorganic arsenic was detected in most samples, with concentrations ranging from <0.04 to 29.3 mg/kg. [ABSTRACT FROM AUTHOR]

Exploring how organisms overcome geographical barriers to dispersal is a fundamental question in biology. Passive long-distance dispersal events, although infrequent and unpredictable, have a considerable impact on species range expansions. Despite limited active dispersal capabilities, many stick insect species have vast geographical ranges, indicating that passive long-distance dispersal is vital for their distribution. A potential mode of passive dispersal in stick insects is via the egg stage within avian digestive tracts, as suggested by experimental evidence. However, detecting such events under natural conditions is challenging due to their rarity. Therefore, to indirectly assess the potential of historical avian-mediated dispersal, we examined the population genetic structure of the flightless stick insect Ramulus mikado across Japan, based on a multifaceted molecular approach [cytochrome oxidase subunit I (COI) haplotypes, nuclear simple sequence repeat markers and genome-wide single nucleotide polymorphisms]. Subsequently, we identified unique phylogeographic patterns, including the discovery of identical COI genotypes spanning considerable distances, which substantiates the notion of passive long-distance genotypic dispersal. Overall, all the molecular data revealed the low and mostly non-significant genetic differentiation among populations, with identical or very similar genotypes across distant populations. We propose that long-distance dispersal facilitated by birds is the plausible explanation for the unique phylogeographic pattern observed in this flightless stick insect. [ABSTRACT FROM AUTHOR]

Simple Summary: The fall armyworm, Spodoptera frugiperda, is an invasive migratory insect pest that first arrived in Japan in early July 2019. Since then, the species has immigrated to Japan mainly in the summer monsoon season and inflicted damage mainly on the maize used as animal feed in the western region, where major immigrations occur. In this study, to know the precise arrival timing and area of S. frugiperda for the purposes of pest management, a prediction method for its overseas migration from neighboring source areas was developed. The method combines numerical weather predictions and migration calculations. The source areas and take-off and flight behavior of S. frugiperda were input into a migration model that output daily migration prediction figures. A prediction evaluation using 2-year six-point trapping data in Japan showed that the prediction method achieved an average hitting ratio of 78%, indicating the method has sufficient prediction quality for operational use. (1) Background: The fall armyworm, Spodoptera frugiperda, is an invasive migratory insect pest that first arrived in Japan in early July 2019. Since then, the species has immigrated to Japan mainly in the summer monsoon season and inflicted damage mainly on the maize used as animal feed in the western region, where major immigrations occur. In this study, to know the precise arrival timing and area of S. frugiperda for purposes of pest management, a prediction method for its overseas migration from neighboring source areas was developed. (2) Methods: The method uses the Weather Research and Forecast model to give numerical weather predictions and the GEARN-insect model to predict migration. Emigration source areas on the Chinese mainland and the island of Taiwan and the insect's take-off and flight behaviors were input to the GEARN-insect model to calculate the daily migration prediction figures. (3) Results: In a prediction evaluation using 2-year six-point trapping data in Japan, the prediction method achieved an average hitting ratio of 78%. (4) Conclusions: The method has sufficient prediction quality for operational use. The technique may be applicable to other migratory moths immigrating to Japan, such as the oriental armyworm, Mythimna separata. [ABSTRACT FROM AUTHOR]

The population size of the diving beetle Cybister sugillatus Erichson 1834 (Coleoptera: Dytiscidae) has been declining in Japan; therefore, there is a need to understand their fundamental ecology for conservation purpose. Understanding the feeding habits in the larval stage will contribute to habitat restoration and ex situ conservation. In this study, we investigated the effects of the availability of different kinds of prey, such as Odonata nymphs and tadpoles, on larval growth of C. sugillatus. The results showed that Odonata nymphs were the preferred prey for larval growth because C. sugillatus larvae did not show significant growth on tadpoles alone. This trend was also observed in other Cybister species. Our results suggest that habitat restoration requires the development of an environment rich in a variety of aquatic invertebrates, including Odonata nymphs. In ex situ conservation, stable rearing and breeding of C. sugillatus can be made possible by providing them with Odonata nymphs as food. [ABSTRACT FROM AUTHOR]

The Japanese members of Haliplidae were reviewed and 13 species in two genera are recognized. A new species, Haliplus morii sp. nov. is described from Honshu; it is similar to Haliplus japonicus Sharp, 1873, but belongs to a different subgenus. Haliplus diruptus J. Balfour-Browne, 1946, syn. nov. is treated as a junior synonym of Haliplus kotoshonis Kano & Kamiya, 1931. The records of Haliplus davidi Vondel, 1991 from Japan are regarded as misidentifications of H. kotoshonis. Haliplus basinotatus latiusculus Nakane, 1985, syn. nov. is treated as a junior synonym of H. basinotatus. Haliplus angustifrons Re'gimbart, 1892 known from south and southeast Asia, is newly recorded from Japan. [ABSTRACT FROM AUTHOR]

Background and Aims Plants have evolved various defences against herbivores, including direct chemical and structural defences and co-opted biological defences by predatory insects. However, the effects of abiotic habitat conditions on the quantitative expression of defence traits of spiny species have not been elucidated. Methods Here, we investigated whether a spiny deciduous tree, Aralia elata (Miq.) Seem. changes its defence expression across light and nutrient gradients. We measured allocation to spines and C-based secondary metabolites (condensed tannins and total phenols) on A. elata plants growing across light and nutrient gradients in situ in natural landscapes in Japan. Second, we examined the effects of light and soil nutrient condition on allocation to shoot organs, spines and chemical defences of juveniles of two genotypes of the species, respectively spiny (mainland population) and non-spiny (island population), grown in a glasshouse. Key Results In the field investigation, absolute spine mass, spine mass fraction, total phenols and condensed tannins all responded positively to canopy openness. Total phenol content was also negatively related to soil N. In the glasshouse, spiny genotype individuals had less total biomass, had lower stem allocation and were shorter than non-spiny genotype individuals. In spiny genotype trees, both spine mass fraction and total phenols decreased under low light conditions. Nutrient additions had negative effects on spine mass fraction and total phenols, but no effect on absolute spine mass. Conclusions These results suggest that development of spines is costly for A. elata and receives greater allocation when carbohydrate supply is more plentiful. Thus, light is a more important determinant of spine allocation than soil nutrients for A. elata. [ABSTRACT FROM AUTHOR]

In defensive mimicry, resemblance between unequally defended species can be parasitic; this phenomenon has been termed quasi-Batesian mimicry. Few studies have used real co-mimics and their predators to test whether the mimetic interactions were parasitic. Here, we investigated the mimetic interaction between two well-defended insect species, the bombardier beetle Pheropsophus occipitalis jessoensis (Coleoptera: Carabidae) and the assassin bug Sirthenea flavipes (Hemiptera: Reduviidae), using their potential predator, the pond frog Pelophylax nigromaculatus (Anura: Ranidae), which coexists with these insect species in the same habitat in Japan. We observed behavioural responses of this frog species (adults and juveniles) to adult Ph. occipitalis jessoensis and adult S. flavipes under laboratory conditions. Among the frogs, 100% and 75% rejected Ph. occipitalis jessoensis and S. flavipes, respectively, suggesting that, compared with the assassin bug S. flavipes, the bombardier beetle Ph. occipitalis jessoensis is more well-defended against frogs. An assassin bug or a bombardier beetle was provided to a frog that had encountered the other insect species. Frogs with a history of assassin bug encounter demonstrated a lower rate of attack toward bombardier beetles. Similarly, frogs with a history of bombardier beetle encounter demonstrated a lower rate of attack toward assassin bugs. Therefore, both the bombardier beetle Ph. occipitalis jessoensis and the assassin bug S. flavipes benefit from the mimetic interaction. [ABSTRACT FROM AUTHOR]

Burcucumber (Sicyos angulatus), first introduced in 1952 from North America to Japan, has recently become a seriously invasive alien species that has spread nationwide. The pollination mode is likely to play a crucial role in seed production and invasion. Burcucumbers have been characterized as self‐compatible flowers with distinct anthers and stigmas, indicating pollen vector‐mediated pollination. In this study, we aimed to describe the floral biology of burcucumbers and clarify their relationships with pollinators. We found that: (1) primarily native insects (at least 70 species) repeatedly visited burcucumbers, both during the day and night; (2) in terms of visitation frequency and pollen‐carrying load, honeybees, vespid wasps, and hoverflies were the most important diurnal pollinators, followed by sphingid and noctuid moths as nocturnal ones; and (3) the production of highly concentrated nectar as floral reward coupled with floral scents, predominantly aliphatic compounds such as heptanal and hexanol, may mediate the visitation of floral visitors. Our observations confirmed that burcucumber visitation is dominated by native pollinators, indicating the integration of burcucumbers into native pollinator webs. Our findings highlight the significance of a generalized pollination system in alien plants to overcome reproductive failure within a new region. [ABSTRACT FROM AUTHOR]

Elucidating the mechanism of formation of biota on islands will contribute to our understanding of the evolutionary mechanisms that generate biodiversity. In this study, we focus on the evolutionary history of Ephemera orientalis , which is distributed in East Asia. Phylogenetic analyses were performed using the mitochondrial DNA 16S rRNA, cytochrome oxidase subunit I and the nuclear DNA histone H3 regions. We found that these mayflies exhibit genetic differentiation between the Japanese and Korean populations. The Tsushima population, which is located between the Japanese Islands and the Korean Peninsula, was positioned genetically as a continental clade. The populations of the Fuji-Goko Lakes and Lake Ashino-ko in Central Japan were genetically differentiated from the other populations. The genetic structures over a wide area of the Japanese Islands were confirmed and a loose genetic regionality was observed, which was thought to result from secondary contact of the north-eastern and south-western lineages after their long separation by a geohistorical division event. We have gathered important knowledge regarding the evolutionary history of organisms on islands and investigated the colonization and isolation of biological populations within a species with high dispersal ability. [ABSTRACT FROM AUTHOR]

Simple Summary: Parasites sometimes manipulate host behavior to effectively utilize their hosts. The parasitism of host-manipulating parasites of hornets (Vespa spp.) was examined for baited or hand-collected hosts. There, two groups of endoparasites that sterilize their hosts, a nematode species, Sphaerularia vespae, and two species of parasitic insects, Xenos spp., were recovered during the survey. Although the nematode parasitism was scarcely observed (4 out of 1641 host hornets), the parasitism of Xenos spp. varied among host species between 0 and 17%. Interestingly, the rate of hornets parasitized by Xenos spp. was higher in baited individuals than in hand-collected ones. Because the bait trap attracts feeding (not foraging for colony) individuals, the parasitism manipulates the host to visit a feeding site, and the result is in good accordance with previous observations; i.e., parasitized hosts frequently visit and stay at feeding sites instead of foraging and reproducing. The present study could be the first case to quantify the Vespa host manipulation of Xenos spp. Genetically, both the Xenos spp. had four haplotypes in the mitochondrial cytochrome oxidase subunit I gene, and these were close to Japanese and some other East Asian genotypes. The parasitism of two groups of host-manipulating parasites of hornets was examined in Kyoto, Japan. Vespa mandarinia (661 individuals), V. simillima (303), V. analis (457), V. ducalis (158), V. crabro (57), and V. dybowskii (4) were collected either by bait trap or hand collection with an insect net, and examined for their parasites. An endoparasitic nematode, Sphaerularia vespae was isolated from three overwintered gynes of V. mandarinia and a gyne of V. ducalis. While endoparasitic insects, Xenos spp., were recovered from 13 V. mandarinia, 77 V. analis, two V. ducalis, and three V. crabro, and those recovered from V. analis and others were molecularly identified as X. oxyodontes and X. moutoni, respectively. Comparing Xenos parasitism level and capturing methods, the parasitism level was significantly higher in trapped hosts than in hand-collected ones, suggesting that stylopized hosts are more strongly attracted to the food source (bait trap) compared with unparasitized hosts. The genotypes of S. vespae were identical to each other, and near identical to its type population. While each of the two Xenos spp. showed four mitochondrial DNA haplotypes. A phylogenetic comparison suggested that Xenos haplotypes found in the present study are close to those previously reported from Japan and other Asian countries. [ABSTRACT FROM AUTHOR]

To evaluate the dietary antioxidant content of insects, we analyzed the hydrophilic oxygen radical absorbance capacity (H-ORAC) of silkworms (Bombyx mori Linnaeus), and rice grass hoppers (Oxya yezoensis Shiraki), which have been used as edible insects in Japan for many years, and Japanese buff-tip moths, Phalera flavescens (Bremer et Grey), which feed on cherry blossom tree leaves. Among these three insects, the H-ORAC value was highest (7455 ± 185 µmol Trolox eq./100 g FW) in O. yezoensis adults, followed by B. mori pupae (4417.5 ± 270.1), B. mori larvae (4280 ± 189.1), and P. flavescens larvae (4112.5 ± 409.4). The H-ORAC of all three insect species were more than twice those of most fresh vegetables, suggesting high antioxidant potential. [ABSTRACT FROM AUTHOR]

Basic ecological information (e.g. habitat or distribution) is indispensable for conserving endangered species. The giant water bug Kirkaldyia deyrolli is an aquatic insect in the large stink bug family (Belostomatidae). It inhabits ponds and is a critically endangered species. In this study, we developed a species‐specific primer–probe set (the cytochrome c oxidase I region in mitochondrial DNA) that was used in real‐time polymerase chain reaction (PCR) assays to detect K. deyrolli environmental DNA (eDNA). Next, using eDNA analysis, we investigated the presence of K. deyrolli in 89 study ponds (including one pond that had already been identified as the habitat of this species) in Shimane Prefecture, Japan. The eDNA of K. deyrolli was detected in 11 of these 89 ponds. Furthermore, when the traditional method of direct capture survey was carried out in four of the 10 ponds where K. deyrolli eDNA had been detected and no prior occupancy information for this species was available, the capture of one K. deyrolli (female) was successful in only one pond. This study showed that combining eDNA analysis and direct capture methods can lead to discovering previously unknown habitats essential for conserving an endangered species. [ABSTRACT FROM AUTHOR]

Limited resources intensify interspecific competition and constrain the survival and distribution of species. A restricted, spatially isolated, small island can also pronounce this effect, as predicted in the island biogeography. This study compared the summer diets of sympatric carnivores, red foxes, raccoon dogs, Japanese martens, and Japanese weasels on the small island Izushima and evaluated niche partitioning, especially focusing on their insectivory. The results showed that insects were the main summer food source for all four species, with a significant overlap in their diets. However, in-depth investigation on insectivory down to the level of species and genera revealed that the species differences were more pronounced. Raccoon dogs frequently fed on ground-dwelling beetles, and Japanese martens fed on several arboreal beetles, while red foxes were less dependent on insects and more biased toward larger prey such as mammals and birds, and Japanese weasels foraged more on smaller prey, thereby reflecting niche partitioning between these species owing to differences in foraging ecology under the constrains of their body sizes. [ABSTRACT FROM AUTHOR]

Alpine and subalpine moorland ecosystems contain unique plant communities, often with many endemic and threatened species, some of which depend on insect pollination. Although alpine and subalpine moorland ecosystems are vulnerable to climatic change, few studies have investigated flower-visiting insects in such ecosystems and examined the factors regulating plant-pollinator interactions along altitudinal gradients. Here, we explored how altitudinal patterns in flower visitors change according to altitudinal shifts in flowering phenology in subalpine moorland ecosystems in northern Japan. We surveyed flower-visiting insects and flowering plants at five sites differing in altitude in early July (soon after snowmelt) and mid-August (peak growing season). In July, we found a higher visiting frequency by more variable insect orders including dipteran, hymenopteran, coleopteran, and lepidopteran species at the higher altitude sites in association with the mass flowering of Geum pentapetalum and Nephrophyllidium crista-galli. In August, such altitudinal patterns were not observed, and dipteran species dominated across the sites due to the flowering of Narthecium asiaticum and Drosera rotundifolia. Our study provides key baselines for the detection of endangered biotic interactions and extinction risks of moorland plants under ongoing climate change. [ABSTRACT FROM AUTHOR]

Cymbella janischii, an invasive species of diatom, has been broadening its geographical range in Japan since 2004, flourishing in substantial colonies in river beds. As thick and mucilaginous colonies of this diatom often cover large areas of river beds, this elicits concerns regarding the potential alteration of sedimentary bottom structures and resultant effects on the native ecosystems. The presence of the diatoms growing on the body surface of two aquatic beetles, Grouvellinus nitidus (Elmidae) and Ectopria opaca (Psephenidae) in a Japanese river was confirmed. This constitutes the inaugural documentation of invasive diatoms having a specific relationship with native aquatic insects at an individual level. [ABSTRACT FROM AUTHOR]

Euborellia (Anisolabididae: Anisolabidinae) is one of the most speciose genera of earwigs (Dermaptera), and its species-level classification is difficult. To settle the classification of brachypterous species with abbreviated tegmina recorded from East and Southeast Asia, we examined the morphology and reproductive isolation of three tentative Euborellia species, and analyzed the DNA barcoding region of the mitochondrial cytochrome oxidase subunit I (COI) gene. The observed complete reproductive isolation among the three Euborellia taxa and considerable differentiation in the COI sequences clearly show that each should be treated as a separate species. Based on morphology, distribution and the DNA sequence, we identify Euborellia sp. 1 of Malaysia as E. annulata (Fabricius), a circumtropical cosmopolitan with no records of a fully winged form. Samples from Ioto Island (= Iwo-jima Island: Ogasawara Islands, southern Japan) were also identified as this species. Euborellia sp. 3, from the main islands of Japan, was generally larger and lacked a Y-shaped pigmented area on the penis lobe, which is characteristic of Euborellia sp. 1. We propose reinstating E. pallipes (Shiraki) as the oldest name for this taxon. Euborellia sp. 2, even the brachypterous form, can be distinguished from these two species by its paler coloration (particularly the femora), ecarinate post-abdomen, and the shape of the male genitalia (parameres). We tentatively identify this species as E. philippinensis Srivastava based on the morphology of the brachypterous form, although the macropterous form cannot be distinguished from E. femoralis (Dohrn). [ABSTRACT FROM AUTHOR]

The carabid beetle Nebria taketoi Habu, 1962 is endemic to the high-altitude mountains of Honshu, Japan; due to its rarity, it is one of the least taxonomically studied species among Japanese Nebria. This study taxonomically revised N. taketoi based on morphological comparisons, mainly of the endophallus in males, and geometric morphometrics of the pronotum, a taxonomically useful external character. Specimens previously identified as N. taketoi were found to belong to at least two species: N. taketoi, with a currently confirmed distribution in the northern Hida Mountains (type locality: Mikurigaike, Mount Tateyama), and N. kobushicola sp. nov. from the Okuchichibu and Yatsugatake mountains (type locality: Mount Kobushigatake). Species identities in populations from other localities could not be determined, as male specimens for endophallus examinations were unavailable. However, some populations may consist of species distinct from N. taketoi and N. kobushicola, based on their distribution and morphometric features. Based on comparative morphology of the endophallus, N. kobushicola shares features more similar to N. niohozana Bates, 1883 and N. dichotoma Sasakawa, 2020 than to N. taketoi. [ABSTRACT FROM AUTHOR]

Riffle beetles (Coleoptera: Elmidae) are freshwater insects, and both adult and larval stages primarily inhabit running water. Therefore, environmental factors such as current velocity and substrate characteristics are crucial for the habitat of elmid beetles. The effects of substrate size structure, water depth, current velocity, and distance from terrestrial areas were evaluated for the adult and larval abundance of three common riffle beetles, Stenelmis nipponica Nomura, Zaitzevia awana (Kono), and Zaitzeviaria brevis (Nomura), and other cohabiting aquatic insects in a middle reach of the Mukogawa River, western Japan. The substrate size structure was summarized using principal component analysis, and the effects of environmental factors were analyzed using best subsets multiple regression. In summer (August), the three elmid species tended to be more abundant in the shallow quadrats of coarse-grained substrates, and substrate preference differed among species and stages. Current velocity and proximity to the terrestrial area were not significant for S. nipponica and Z. brevis, whereas adult Z. awana preferred faster-flowing currents and needed to the distance from the terrestrial areas. In winter (December), only the substrate size structure affected the abundance of adult elmid beetles. Although elmid beetles require highly sensitive habitats, they are easily surveyed. Therefore, they are convenient indicators of riverbed environments. Implications for insect conservation Preference of substrate sand size as their habitat differ among stages and seasons. Diverse substrate condition would be needed to conserve elmid beetles. [ABSTRACT FROM AUTHOR]

Forensic entomology (FE) involves the collection and analysis of necrophagous insects and arthropods for postmortem interval estimation based on their growth and succession. In Japan, research on FE is limited, and the predominant species of necrophagous insects and their distribution have not been clarified. The present study aimed to clarify the actual situation of insects, targeting Diptera collected from human cadavers, in Chiba Prefecture. We targeted the cases for which specimens could be collected from forensic autopsies conducted at the Legal Medicine Department of Chiba University Graduate School of Medicine or from human bodies handled by the Chiba Police in 2019. We specifically chose cases from which adult insects could be bred. Fifty cases were applicable, and 47 cases were successful in rearing adult flies. Sixteen species of Diptera were identified: six species of Calliphoridae, four species of Sarcophagidae, and a few species of Fanniidae, Muscidae, Phoridae, Piophilidae, and Stratiomyidae. The most frequently observed species were Lucilia sericata (20 cases) and Chrysomya pinguis (18 cases). For the first time, globally, we recorded the presence of Fannia prisca in a human cadaver. In conclusion, this is the first report to reveal the presence of carrion flies in human death cases in Chiba Prefecture, Japan. Research in FE is important in the context of the Japanese natural and social environment since this can aid forensic investigations conducted by authorities. [ABSTRACT FROM AUTHOR]

Little is known about the ecology of insect species in the hyporheic zone of rivers, despite its importance in understanding how species survive in specialized habitats. We report on the life history and trophic characteristics of the hyporheic stonefly species Alloperla ishikariana Kohno, 1953 (Order: Plecoptera, Family: Chloroperlidae) in a gravel-bed river in northern Japan, using year-round sampling of both benthic and hyporheic larvae, as well as flying adults in the riparian zone. Adults emerged between May and August, and the larval cohort structure consisted of three sized groups with some sex dimorphism in their body size, with an average growth rate of 0.0043 mg/day. Diet analyses based on C and N stable isotope ratios indicated minimal ontogenetic diet shifts. In contrast, the temporal diet shift was more apparent with higher dependence on Oligochaeta in winter, with an increasing dependence on Chironomidae in spring and early summer. Other insect taxa, namely, Leuctridae and small-sized Lepidostoma, demonstrated a high to moderate affinity for the hyporheic zone. Alloperla ishikariana spent most of its larval stage in the hyporheic zone. With adults living from 7 to 10 days, A. ishikariana completes a life span of approximately 3 years with its larval stage in the dark. [ABSTRACT FROM AUTHOR]

Understanding temporal variation in mechanisms and factors shaping metacommunity is an important issue of community ecology. The relative importance of different assembly mechanisms, such as dispersal and environmental filtering, can vary through time in dynamic systems, whereas it is still unclear how different dispersal modes affect temporal patterns of the variation. We investigated metacommunity structures of fish and aquatic insects with flying adults in spring, summer, and autumn in drainage ditches of paddy fields in the Kita River basin, Japan, where agricultural water management and flood events cause seasonal flow changes. Using redundancy analysis and variation partitioning, we examined how the variation of these metacommunity structures was explained by local environmental factors and two types of spatial factors (overland based and watercourse based). Fish metacommunities were mainly influenced by local environmental factors (e.g., water depth) in summer, and by watercourse‐based spatial factors (e.g., distance to downstream rivers) in spring and autumn. As fishes are obligate aquatic dispersers, increased hydrological connectivity among habitats in summer weakens the dispersal limitation from downstream rivers and enables species to track environmentally preferred habitats. In contrast, only overland‐based spatial factors (e.g., spatial patterns based on overland distance) significantly affected aquatic insect metacommunities in summer and autumn. These results suggest that regional and landscape variables can influence their metacommunity patterns more than the local environment. We conclude that the dynamic nature of the environment and dispersal modes can interactively influence metacommunity structures in temporally connecting habitats. [ABSTRACT FROM AUTHOR]

Cultivated Japanese pear varieties, mostly showing self‐incompatibility, require pollen transfer from other varieties. To elucidate the underlying mechanisms of open Japanese pear insect pollination, we first collected flower‐visiting insects using plastic vials and sticky traps in orchards located at different regions in Japan. Results showed that insects assigned to the families Andrenidae (Hymenoptera), Apidae (Hymenoptera), Halictidae (Hymenoptera), Syrphidae (Diptera) and Empididae (Diptera) are abundant in the orchards. Second, we restricted the flower‐visiting insects to access Japanese pear flowers using bags with mesh sizes of 0, 2 and 3.5 mm. Results indicated that insects which allowed to pass through bags with 3.5‐mm mesh size but not through bags with 2‐mm mesh size contribute primarily to pollination, represented as the fruit‐set ratio and seed number. Third, we measured head and thorax widths of the flower‐visiting insects and counted pollen grains on their body surfaces to estimate their pollination potential. Results indicated that insects assigned to the families Andrenidae, Halictidae, Syrphidae, Bibionidae (Diptera) and Muscidae (Diptera), including species with both widths smaller than 3.5 mm, harbour large quantities of Pyrus pollen grains, in addition to Apis mellifera (Apidae) with both widths greater than 3.5 mm. Consequently, the families Andrenidae, Apidae, Halictidae and Syrphidae might be the most important insect families for Japanese pear pollination. However, species identification of the flower‐visiting insects showed no common key species that contribute remarkably to pollination services other than A. mellifera. Consecutive insect collection using plastic vials and sticky traps demonstrated that compositions of the flower‐visiting insects are fluctuating continuously in the orchards. Nevertheless, year‐to‐year fluctuation of the fruit‐set ratio was less pronounced in open‐pollinated orchards than in hand‐pollinated orchards. These results suggest that mutual complementation among diverse pollinator species might be the mechanism underlying open Japanese pear insect pollination. [ABSTRACT FROM AUTHOR]

The responses of assemblages and ecosystems to river intermittency are often considered on large spatial scales, such as those associated with the Köppen climate classification. However, river intermittency may naturally occur even in humid regions, and the effects may differ from those where intermittency occurs throughout the area. This study aimed to examine the differences in taxonomic and trait composition of aquatic insects between intermittent rivers in the Seto Inland Sea watersheds and neighboring humid-temperate rivers in Japan using national census data. While the climate in the most part of the Japanese Archipelago is categorized as humid-temperate, and rivers are usually perennial, local climate in the Seto Inland Sea watersheds has low summer precipitation compared with that in neighboring regions, thereby resulting in river intermittency. Consistent with the previous studies in the regions where rivers are intermittent on a large spatial scale, we observed that aquatic insects with multivoltinism and/or aerial respiration notably tolerated river intermittency. In contrast, the aquatic insect fauna in Japanese intermittent rivers represented subsets of those in the humid-temperate rivers, although previous studies such in Mediterranean regions have reported high endemism and species diversity in intermittent rivers. These results highlight the importance of exploring the role of river intermittency on small to medium spatial scales, as well as on large scales, to project effects of ongoing and future climate changes on species diversity. [ABSTRACT FROM AUTHOR]

This paper presents the first case of the successful eradication of a Coleoptera pest species over a wide area using a combination of male annihilation technique (MAT) and sterile insect technique (SIT) application. The sweet potato weevil, Cylas formicarius, is one of the most destructive and widely distributed pests of sweet potato, Ipomoea batatas. A project to eradicate it was launched in 1994 on Kume Island, Okinawa Prefecture, Japan. The MAT application was first used from November 1994 to January 1999 to reduce the density of wild populations. The distribution and densities of weevils were assessed by trapping them and surveying infestation rates in wild hosts and sweet potatoes in the field. The C. formicarius populations were suppressed by approximately 90% and plant infestations were reduced from 9.5% to less than 0.1% by using the MAT. Then, hundreds of thousands to millions of sterile weevils were released each week (ca. 460 million in total from 1999 to 2012). As a result, based on an analysis of 12748 stems and 48749 tubers, no weevil infections were detected in the stems or tubers of sweet potato since 1997. Since 2009, almost no wild weevils were captured in traps, and in wild host and sweet potato surveys no weevils have been found in any of the 580 locations and 8833 samples since October 2011. As of 28 December, 2012, C. formicarius is considered to have been eradicated from Kume Island. This paper describes the process of eradicating C. formicarius using SIT application integrated with MAT application for the first time and discusses some of the main challenges associated with the weevil eradication campaignl. [ABSTRACT FROM AUTHOR]

Simple Summary: This article discusses the inclusion of insects in Japanese myths. It is believed that the Japanese have more cultural affinity towards insects when compared to elsewhere in the world. It is reasonable to expect that this attitude toward insects is based on the prevalence of insects in Japanese myths. However, insects appear only seven times in the texts that were reviewed in this study, and are only twice presented in a positive light. Gods and emperors in Japanese lore are not commonly depicted as speaking to insects, or as instructing them to work. Neither are gods, nor humans, portrayed as taking the form of insects. In conclusion, relationships between gods, emperors, and insects are sparse in Japanese myths. In terms of cultural entomology, modern Japanese attitudes toward insects, and the origin thereof, require further investigation. Japanese people are perceived to have a relatively more favorable disposition towards insects than individuals from other nations. Given that insects frequently appear in myths from all over the world, I researched Japanese mythology as a potential origin of this positive outlook toward insects. I reviewed the ancient records Kojiki, Nihonshoki, and Fudoki, and found seven cases where insects appear. In all cases, the insects played relatively minor roles. They did not speak, nor were they under the command of gods or emperors. They did not feature as main characters in ancient poetry, and gods/emperors did not take the shape of any insects. In only two instances were insects featured in a positive light. In general, relationships between gods, emperors, and insects are weak in Japanese mythology, and hence mythology does not appear to be the primary source of Japanese affinity for insects. [ABSTRACT FROM AUTHOR]

Insect pests, particularly seed‐feeding flies, can cause serious damage to the fruits of many wild orchid species. Evidence of fly damage has been observed in 55 orchid species, belonging to 25 genera, distributed throughout Japan. Although some authors suggested that the observed increase in fly damage to orchids in recent years is related to the introduction of exotic species, the timing and route of spread remain unclear. We examined herbarium specimens of seven orchid species, collected between 1923 and 2016, to collect coarctate pupae and empty puparia, with minimal damage to the specimens. Genomic DNA was then extracted from the insect tissue and species were identified using mitochondrial cytochrome oxidase subunit 1 barcode regions. Long amplicons (660 base pairs [bp]) were obtained from 45.2% of samples and short amplicons (162 bp) were obtained from 90.3% of samples. In total, 51 of 62 samples had nucleotide sequences homologous to Japanagromyza tokunagai, with specimens distributed across collection years and geographic locations. Therefore, the severe damage to Japanese orchids observed in recent years is not related to the recent introduction of an exotic species; it may be related to a rapid increase in a native species. This work highlights the value of herbaria as important resources for elucidating the history and distribution of parasitic insects. [ABSTRACT FROM AUTHOR]

The pragmatic management of invasive alien species should integrate two essential items: 1) management interventions and 2) a spatially explicit management plan. Predicting the future expansion of target species in a region at the early invasion stage is an important step toward the establishment of a spatially explicit management plan. However, information regarding the distributions of target species is limited, making it challenging to predict range expansions. In the present study, we established a simulation model that could predict the future expansion of the invasive insect Aromia bungii, which is harmful to Prunus trees (including cherry trees [Cerasus × yedoensis]), in Japan. We employed a virtual ecology approach that simulated species dynamics based on a simple model in Saitama Prefecture, which is in the Kanto region of Japan. Since the first record of the species in this region of Japan in 2013, its range has expanded dramatically. Three candidate pathways and combinations of these for the range expansion of A. bungii were tested to identify the major proxies of expansion for this species, followed by the validation of these results using occurrence records for the species through 2019. Both the river density model and combined river and road density models showed good predictive performance. Using these models, we established a predictive map of the future expansion of this species in the wider range of the simulation area. Based on the results, we recommend concentration of management efforts in the mid-northeast region of the Saitama Prefecture. [ABSTRACT FROM AUTHOR]

Animals affect element cycling in ecosystems by consumption and excretion. Amphidromous shrimps frequently dominate low-mid altitude streams, where downstream connectivity to oceans is sustained. Although shrimps' direct influence on benthic communities has been studied, little is known about their influences on nutrient cycling. Here, we hypothesized that the dominance of shrimps alters nutrient mineralization by benthic macroinvertebrates in streams due to the difference in the quality and quantity of excretion between shrimps and aquatic insects. We tested this hypothesis through a field manipulative experiment, excretion measurements of animals, and field surveys. In the field manipulative experiment, the presence of shrimps slightly decreased the biomass of aquatic insects but tripled total benthic macroinvertebrate biomass directly through their own biomass. The mass-specific NH4+ excretion rate by shrimps was similar to aquatic insects, and the areal NH4+ excretion by benthic macroinvertebrates was increased by 2.5 times in the presence of shrimps. In contrast, shrimps excreted significantly less soluble reactive phosphorus (SRP) than aquatic insects, and the presence of shrimps did not affect areal SRP excretion by benthic macroinvertebrates. The field survey showed a positive correlation of NO3− concentration with the shrimp density, inferring the excess NH4+ was nitrified. Although the nutrient concentration of stream water is frequently attributed to watershed conditions, the results of this study indicate that downstream connectivity to oceans may also influence nutrient dynamics of the stream through the density of amphidromous shrimps. [ABSTRACT FROM AUTHOR]

The distribution area of a species is determined by a combination of factors and since each species of aquatic insect has adapted to drastically changing environments along river channels, they are excellent targets for study. Considering these factors, we focused on three Ephemera mayflies inhabiting the Japanese Archipelago and investigate their niche differentiation patterns. A total of 29 study sites were established within the Asahi-gawa River System to study the relationship between various environmental factors and these mayflies' population structures. From the results of RDA and/or GLMMs, Ephemera japonica tended to distribute in locations with a small degree of canopy openness and a lot of cobbles and boulders. In contrast, Ephemera orientalis tended to distribute in locations with small riverbed slope degree, and small grain size. The distribution area of Ephemera strigata was intermediate between that of E. japonica and E. orientalis. At several study sites, although the distribution patterns appeared irregular due to surrounding environments affected by artificial structures, these patterns can be explained by examining the environmental factors around dams. These results on geographical fine-scaled niche differentiation within a closely related species provide significance knowledge to support understanding of the mechanisms of species coexistence and biodiversity creation. [ABSTRACT FROM AUTHOR]

Perlomyia gakken sp. nov. (Plecoptera: Leuctridae) from Kyoto Prefecture, Honshu, Japan, is described and illustrated. This new species is distinguished from all other Perlomyia species by having a remarkably long and slender epiproct with a crochet hook shape at tip. Although, this new species is most similar to P. kappa Sivec and Stark, 2012, but can be discriminated from P. kappa by the three morphological differences: (1) cercus with small spine-like apex (long terminal spine in P. kappa), (2) epiproct slightly swollen at middle in lateral aspect (swollen basally in P. kappa), and (3) epiproct like a crochet hook shape apically in lateral aspect (expanded apically in lateral aspect in P. kappa). A checklist and type localities map for 25 currently recognised Perlomyia species are also presented. [ABSTRACT FROM AUTHOR]

BACKGROUND: In order to better understand the population dynamics of invasive species in their native range, we developed two predictive phenological models using the ubiquitous invasive insect pest, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), as the model organism. Our work establishes a zero‐inflated negative binomial regression (ZINB) model, and a general additive mixed model (GAMM) based on 11 years of black light trap monitoring of H. halys at three locations in Japan. RESULTS: The ZINB model indicated that degree days (DD) have a significant effect on the trap catch of adult H. halys, and that precipitation has no effect. A dataset generated by 1000 simulations from the ZINB suggested that higher predicted trap catches equated to a lower probability of encountering a zero‐count. The GAMM produced a cubic regression smooth curve which forecasts the seasonal phenology of H. halys as following a bell‐shaped trend in Japan. Critical DD points during the field season in Japan included 261 DD for first H. halys adult detection and 1091 DD for peak activity. CONCLUSIONS: This study establishes the first models capable of forecasting native H. halys population dynamics based on DD. These robust models practically improve population forecasting of H. halys in the future and help fill gaps in knowledge pertaining to its native phenology, thus ultimately contributing to the progression of efficient management of this globally invasive species. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A microbiological study was conducted on 41 insect product samples (29 raw frozen [21 domestic and 8 imported], 10 powdered, and 2 processed), which were commercially available in Japan. The total aerobic count for raw frozen insects was 5.61 log cfu/g (range: 2.52-8.40), whereas the powdered insect count was 2.89 log cfu/g (range: 1.00-4.57). The bacterial count was significantly higher in raw frozen insects ( p < 0.05). The coliform count for the raw frozen insects ranged from <1 to 6.90 log cfu/g, and that for the powdered insects ranged from <1 to 1.00 log cfu/g. The number of samples with values above the detection limit was significantly higher in raw frozen insects ( p < 0.05). The detection frequencies of aerobic spores (<1-4.63 log cfu/g), anaerobic spores (<0-4.40 log cfu/g), and Bacillus cereus (<1.7-3.83 log cfu/g) showed no sample type-related significant difference. Listeria spp. was isolated from four samples of raw frozen insects, one of which was Listeria monocytogenes . We did not detect any of the following: Salmonella spp., Shiga toxin-producing E. coli (STEC), Campylobacter jejuni/coli , or pathogenic Yersinia . We isolated insect products retailed in Japan harboring food poisoning bacteria, including L. monocytogenes and B. cereus . In particular, raw frozen products displayed high levels of hygienic indicator bacteria.

Comprehensive biodiversity data is crucial for ecosystem protection. The Biome mobile app, launched in Japan, efficiently gathers species observations from the public using species identification algorithms and gamification elements. The app has amassed >6 million observations since 2019. Nonetheless, community-sourced data may exhibit spatial and taxonomic biases. Species distribution models (SDMs) estimate species distribution while accommodating such bias. Here, we investigated the quality of Biome data and its impact on SDM performance. Species identification accuracy exceeds 95% for birds, reptiles, mammals, and amphibians, but seed plants, molluscs, and fishes scored below 90%. Our SDMs for 132 terrestrial plants and animals across Japan revealed that incorporating Biome data into traditional survey data improved accuracy. For endangered species, traditional survey data required >2000 records for accurate models (Boyce index ≥ 0.9), while blending the two data sources reduced this to around 300. The uniform coverage of urban-natural gradients by Biome data, compared to traditional data biased towards natural areas, may explain this improvement. Combining multiple data sources better estimates species distributions, aiding in protected area designation and ecosystem service assessment. Establishing a platform for accumulating community-sourced distribution data will contribute to conserving and monitoring natural ecosystems., Competing Interests: KA, YN Employed by Biome Inc, but not financially benefit directly from the publication of this paper, MU, HN No competing interests declared, TG CTO of Biome Inc, and an inventor of the species-identification-AI-algorithm JPN patents 6590417 and US patents 11048969, but not financially benefit directly from the publication of this paper, SF CEO of Biome Inc, and an inventor of the species-identification-AI-algorithm JPN patents 6590417 and US patents 11048969, but not financially benefit directly from the publication of this paper, (© 2024, Atsumi et al.)