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Simple Summary: Rosalia batesi Harold (Cerambycidae) is a longhorned beetle endemic to Japan distributed on the mainland from Hokkaido (north) to Kyushu (south). The beautiful appearance of the adults is renowned not only in Japan but worldwide. The larvae feed in the trunks of broad-leaf trees. Females were attracted to males in laboratory bioassays, which suggested that males produce a sex pheromone. We collected volatiles from R. batesi females and males and found a single male-specific compound. It was identified as 3,5-dimethyl-6-(1-methylbutyl)-pyran-2-one, which is the same compound identified as the pheromone of its European congener R. alpina. This alkylated pyrone is a unique structure among known cerambycid pheromones. In field bioassays carried out with the racemic synthetic pheromone in Japan, both sexes of R. batesi were attracted in significant numbers in a ratio of almost 1:1, indicating that the compound is an aggregation-sex pheromone. The longhorned beetle Rosalia batesi Harold (Coleoptera; Cerambycidae) is endemic to Japan, where its range extends from Hokkaido to Kyushu. The colorful adults are well-known to entomologists and collectors worldwide. It is a hardwood-boring species with larvae that develop in dead broad-leaf trees. In laboratory bioassays, females were attracted to males, which suggested that males produce a sex pheromone. The congeneric species R. alpina is native to Europe, and another congener, R. funebris, is distributed in North America. The pheromone components produced by males of these species had been previously identified as two compounds from different biosynthetic pathways. In the present study, volatiles were collected from beetles of both sexes, and the analyses of the resulting extracts revealed a single male-specific compound, which was identified as 3,5-dimethyl-6-(1-methylbutyl)-pyran-2-one; this is the same compound as the pheromone of the European R. alpina. This alkylated pyrone structure is, so far, unique among known cerambycid pheromones. In field bioassays with traps baited with the racemic synthetic pheromone, significant numbers of both sexes of R. batesi were attracted in an approximately equal ratio, indicating that the compound is an aggregation-sex pheromone rather than a sex pheromone. [ABSTRACT FROM AUTHOR]

Simple Summary: The invasive Asian longicorn beetle Anoplophora glabripennis and native Japanese white-spotted longicorn beetle A. malasiaca show an extensive overlap with host plants, niches, and emergence season. Hybridization between these two species is suspected. The surface of the female body is covered with contact sex pheromones that elicit male mating behavior within species. We evaluated the contact pheromonal activity of crude extract and fractions of female A. glabripennis and revealed a hydrocarbon fraction to show activity; however, it was relatively weak. There might be other, as yet unidentified active compounds in the extract. Only a small number of male A. glabripennis showed mating behavior when they were exposed to the crude extract of female A. malasiaca, whereas a considerable number of male A. malasiaca showed mating behavior when exposed to both female A. glabripennis and A. malasiaca extracts. Gomadalactones are essential contact pheromone components that elicit mating behavior in male A. malasiaca. We, therefore, attempted to detect gomadalactones in female A. glabripennis extract, but without success. We investigated the possible reasons for this phenomenon and the difference in male mate recognition systems between A. glabripennis and A. malasiaca. The Asian longicorn beetle Anoplophora glabripennis is a recently arrived invasive species to Japan. The Japanese native A. malasiaca shows an extensive overlap with A. glabripennis with host plants, niches, and emergence season. Hybridization between these two species is suspected in Japan. The surface of the female is covered with contact sex pheromones that elicit male mating behavior within species. We evaluated the contact pheromonal activity of crude extract and fractions of female A. glabripennis coated on a black glass model and revealed a hydrocarbon fraction and a blend of fractions to show activity but relatively weak, suggesting the presence of other unknown active compounds. Few male A. glabripennis showed mating behavior when they were exposed to a crude extract of female A. malasiaca. However, a considerable number of A. malasiaca males mounted and showed abdominal bending behavior when presented with glass models that were coated with each extract of female A. glabripennis and A. malasiaca. Gomadalactones are essential contact pheromone components that elicit mating behavior in male A. malasiaca; however, we could not detect them in female A. glabripennis extract. Here, we investigated the possible reasons for this phenomenon and the difference in male mate recognition systems between these two species. [ABSTRACT FROM AUTHOR]

Simple Summary: The white-spotted longicorn beetle, Anoplophora malasiaca, is one of the most destructive pests of many fruits and street trees. Effective controls are needed because the effect of marketed insecticides is limited. Entomopathogenic fungi offer a solution, combination with the beetles' contact sex pheromone. The surface of the female body is covered with contact sex pheromone, which we extracted. Males held onto a glass model coated with female extract for 5 h, but males held onto one without extract for <0.3 h. Males that held onto coated model, attached to fabric impregnated with an entomopathogenic fungus, Beauveria brongniartii, picked up significant fungi. The fungi were then transferred to females during mating. Our results indicate that a combination of contact pheromone with a pathogen could improve entomopathogenic infection of both male and female beetles. The white-spotted longicorn beetle, Anoplophora malasiaca, is one of the most destructive pests of horticultural crops and street trees. Effective controls are needed because the effect of marketed insecticides is limited. Entomopathogenic fungi offer a solution, and improving the rate of infection would be a breakthrough in this beetle's control. The combination of pathogenic fungi and the beetle's contact sex pheromone was suggested. The surface of the female body is covered with contact sex pheromone, which elicit male mating behavior. To develop a method for the practical control of this beetle, we evaluated the arrestant activity of female extract containing contact pheromone coated on a black glass model. Males presented with a coated model held on for 5 h (mean) during an 8-h experiment. In contrast, males presented with a control model held on for <0.3 h. Males that held onto coated models attached to fabric impregnated with conidia of the fungus Beauveria brongniartii picked up much conidia, which they then passed on to females during mating. [ABSTRACT FROM AUTHOR]