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Ergatandromorphs are examples of genetic chimeras found in ants, in which they exhibit features of both minor workers and males. In this study, we report a lateral ergatandromorph of Camponotus yamaokai Terayama & Satoh, 1990. The right side of this specimen was characterized as a male and the left side as a minor worker, although some body parts did not show a clear division. The specimen had partially atrophied genitalia on the right side of the metasoma while the genital structures on the left side were absent. The individual engaged in frequent self‐grooming and received trophallaxis and allogrooming from the nestmates. This is the first report of the lateral ergatandromorph in the genus Camponotus, which has few documented cases of gynandromorphism. [ABSTRACT FROM AUTHOR]

For many years, only one species of praying mantis in the genus Hierodula , Hierodula patellifera Serville, had been recorded in Japan. In recent years, however, Hierodula chinensis Werner, a larger species than H. patellifera Serville, has been discovered in Japan, and observations and collections in Japan have increased rapidly. There are reports that in some areas, H. patellifera became locally extinct due to the invasion of H. chinensis. Since females of H. patellifera attract conspecific males by volatile with characteristic calling behavior, a sex pheromone-mediated reproductive interference may exist between the two species. Both males of H. patellifera and males of H. chinensis were strongly attracted to conspecific females and crude headspace extract from conspecific females, while they were not attracted to females of allospecific species or crude headspace extract from allospecific females. These results indicate that sex pheromone-mediated reproductive interference may not exist between H. patellifera and H. chinensis. [ABSTRACT FROM AUTHOR]

The mirid bugs Stenotus rubrovittatus and Trigonotylus caelestialium, which cause pecky rice, have become a threat to rice cultivation in Asia. Damage caused by these pests has rapidly become frequent since around 2000 in Japan. Their expansion pattern is not simple, and predicting their future spread remains challenging. Some insects with wide ranges have locally adapted variations in life‐history traits. We performed laboratory rearing experiments to assess the geographical scale of intraspecific variations in life‐history traits of S. rubrovittatus and T. caelestialium. The experiments were aimed at increasing the accuracy of occurrence estimates and the number of generations per year. These results were compared with previous research, and differences in development rates were observed between populations of different latitudes, but not of the same latitude. Finally, plotting the timing of adult emergence and the potential number of generations per year on maps with a 5‐km grid revealed that they differed greatly locally at the same latitude. These maps can be used for developing more efficient methods of managing mirid bugs in integrated pest management. [ABSTRACT FROM AUTHOR]

Environmental fluctuations can influence invertebrate population dynamics over large spatial scales, and effects of climate change are of particular importance in understanding phenology. In this study, we tested whether changing climate patterns could increase voltinism and emergence synchrony in Stenotus rubrovittatus and drive the mirid bug’s expansion into currently uninhabited areas of Japan. This expansion could have potentially serious economic consequences for the rice industry. We modelled development of S. rubrovittatus in the field applying the effective accumulated temperature model to calculate the theoretical number of generations and the egg hatching dates from 2003 to 2012 based on a high-resolution, daily weather database. We then performed a regional analysis to assess the relationship between population dynamics and range expansion across the study region and also included a local analysis to evaluate how population parameters affect the presence of S. rubrovittatus at local sites in each year. Results showed that distribution expanded with a relative increase in voltinism and with synchrony of egg hatching date. Moreover, we showed that increased voltinism in the previous year positively influenced local population occurrence. This positive effect suggests that the species’ distribution range expands through increased reproduction at both the regional and local scale. Climate-mediated population dynamics play a significant role in range expansion of the mirid bug. [ABSTRACT FROM AUTHOR]

The praying mantis genus Acromantis is characterized by its compound eyes with stripe patterns in the Japanese Mantodea. In the laboratory, we observed that the 1st instar nymphs of Acromantis satsumensis Matsumura had a single stripe on their compound eyes, and one more stripe appeared on both of their compound eyes when they became 2nd instar nymphs. Likewise, the 3rd instars had 3 stripes, the 4th instars had 4 stripes, and so on. These results suggest that the stripe patterns on the compound eyes increase one by one with each molt in A. satsumensis. [ABSTRACT FROM AUTHOR]

In Polistes paper wasps, haploid early males can mate with early emerging females and leave viable offspring. In contrast, diploid early males are eventually sterile because they contribute triploid offspring via diploid sperm. Clarifying the ploidy of early males is important for determining whether early male production is a reproductive strategy for the species. We examined the mating behavior and the ploidy of early males in the Japanese paper wasp, Polistes rothneyi iwatai van der Vecht. Thirteen early males from four colonies were all diploid. Two of the nine early males (22.2%) attempted to mate with females, but only one individual (11.1%) was successful (the female's spermatheca contained spermatozoa). These results suggest that although most early males of P. rothneyi iwatai do not produce offspring, their mating may be linked to the occasional production of triploid females. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we have identified a new sesquiterpene synthase gene (ZSS2) from Zingiber zerumbet Smith. Functional expression of ZSS2 in Escherichia coli and in vitro enzyme assay showed that the encoded enzyme catalyzed the formation of β-eudesmol and five additional by-products. Quantitative RT-PCR analysis revealed that ZSS2 transcript accumulation in rhizomes has strong seasonal variations. To further confirm the enzyme activity of ZSS2 and to assess the potential for metabolic engineering of β-eudesmol production, we introduced a gene cluster encoding six enzymes of the mevalonate pathway into E. coli and coexpressed it with ZSS2. When supplemented with mevalonate, the engineered E. coli produced a similar sesquiterpene profile to that produced in the in vitro enzyme assay, and the yield of β-eudesmol reached 100mg/L. [Copyright &y& Elsevier]

Our previous study demonstrated that among the various T-cell receptor Vb gene segments, T-cell receptor Vb6 gene-bearing T cells are predominant in periodontitis lesions. To explore the clonality of T cells expressing Vb6 T-cell receptor, which is determined by the heterogeneity of the complementarity-determining region 3(CDR3), Vb6-Cb polymerase chain reaction products derived from gingival tissue and peripheral blood of periodontitis patients were analyzed by single-strand conformation polymorphism and nucleotide sequence. Both techniques provided quite similar results in terms of the number of accumulated clones in which clonal accumulation of T-cell receptor Vb6-bearing T cells was found in most periodontitis lesions but not in peripheral blood. From the analysis of deduced amino acid sequences, a possible conserved amino acid residue in the CDR3 region of the periodontitis lesion-derived sequences was found in most patients. This conserved amino acid motif however, was not identified. Furthermore, skewed Jb gene segment usage was observed for expanded clones from periodontitis lesions. Our results suggest that T cells infiltrating periodontitis lesions are responding to a restricted number of antigens or epitopes. [ABSTRACT FROM AUTHOR]

The yellow-legged hornet Vespa velutina has become one of the major alien species in European and East Asian countries. As in its homeland, the invading V. velutina is reported as the major predator of honeybees and is becoming a threat to beekeeping in Europe. However, it remains unknown how V. velutina might affect native hornets when it invades Asia, where a large number of Vespa species are distributed. Thus, by analyzing the mitochondrial cytochrome c oxidase subunit I gene, we investigated whether interspecific mating occurs between V. velutina and Japanese native Vespa spp. Our results showed that the alien V. velutina causes reproductive interference in Japanese native hornet Vespa simillima. Forty-three percent of native V. simillima queens had the sperm of V. velutina males, and among the all V. simillima queens analyzed, 28% only had V. velutina sperm. We did not find evidence of V. velutina queens having the sperm of V. simillima males. These findings suggest that reproductive interference by V. velutina males poses a threat to the native V. simillima populations. A decline of V. simillima may also negatively affect other insects that interact with V. simillima. [ABSTRACT FROM AUTHOR]