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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]

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a polyphagous pest native to the tropical and subtropical Americas, but it has recently invaded the Eastern Hemisphere and spread rapidly. This migratory moth, which can fly long distances, now poses a global threat as a transboundary pest. To establish an efficient management program against this pest, monitoring of its occurrence is essential. Lures impregnated with four synthetic pheromone components of S. frugiperda – (Z)‐9‐tetradecenyl acetate (Z9‐14:Ac), (Z)‐11‐hexadecenyl acetate, (Z)‐7‐dodecenyl acetate, and (Z)‐9‐dodecenyl acetate – are commercially available, and traps baited with them are used for monitoring. However, in Japan, these pheromone traps frequently capture many non‐target moths, particularly Mythimna loreyi (Duponchel) (Lepidoptera: Noctuidae). We therefore reexamined the sex pheromone of S. frugiperda in an attempt to improve the monitoring lures and discovered trace amounts of (Z,E)‐9,12‐tetradecadienyl acetate (Z9E12‐14:Ac) in female extracts at ca. 0.2% of the primary component (Z9‐14:Ac). We verified its activity in males by field trap bioassays as well as antennal electrophysiology and demonstrated that this fifth component enhances the attractiveness of synthetic pheromones composed of the other four components to S. frugiperda and reduces the bycatch of M. loreyi. As Z9E12‐14:Ac is found in pheromones of most Spodoptera species, it may have been a pheromone component in the common ancestor and played a key role in divergence of pheromone systems in the genus Spodoptera. [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]

An emerging invader, the red-necked longicorn beetle Aromia bungii (Faldermann) (Coleoptera: Cerambycidae), has become a major pest of cherry blossom, peach, prune, and Japanese apricot in Japan. The synthetic aggregation-sex pheromone, (E)-2-cis-6,7-epoxynonenal, has been used as a chemical for their monitoring. The longevity of the current lure is, however, only one week. Unlike most Lepidopteran lures, it needs to be emitted in large amount of the pheromone emission for effective attraction. In this study, we surveyed chemical retention materials to determine which improving its longevity. The weights of 7 types of lures were measured for 2 or 3 weeks to determine the weight-loss. The pheromone emission from each lure tended to be correlated to the weight-loss. We analyzed the pheromone emissions from candidate lures for three weeks and compared them to the current lures. The current lure continued pheromone emission for 7 d, whereas the candidate lure continued for 14 d. In field trials, the candidate and current lures were both significantly attractive during the first week compared to the control. However, the candidate lure attracted the beetle to the same extent for over 14 d; its longevity was double that of the current lure, therefore, it could be useful for extended monitoring of this beetle. [ABSTRACT FROM AUTHOR]

The effect of mating disruption by the ground-surface application of 2-cm-long dispensers (mini-dispensers) of 2-butanol against the white grub beetle Dasylepida ishigakiensis Niijima et Kinoshita (Coleoptera: Scarabaeidae) was examined in sugarcane fields on the Miyako Island, Okinawa, Japan. Mating rates and male catches with sex pheromone traps were reduced to a low level comparable to that obtained from a conventional method in which rope dispensers (25 m) were hung at a height of ca. 30 cm along the sugarcane ridges. Both mating rates and male catches were reduced with increasing number of treated mini-dispensers. These results suggest that by using mini-dispensers the amounts of synthetic sex pheromone and plastic resin can be reduced to 1/10-1/5 and 1/6-1/3, respectively, of their conventional application with rope-type dispensers, without impairing the efficiency of mating disruption in this beetle. Furthermore, the amount of labor required for the application of this method is expected to be greatly reduced compared to the rope-type dispenser method. [ABSTRACT FROM AUTHOR]

Oocyte development, age at first reproduction, ovipositing activity and longevity were compared among three groups of Anoplophora malasiaca (Coleoptera: Cerambycidae) female adults that were grown on an artificial diet and provided with mandarin orange (MO), blueberry (BB) and willow (WI) branches after adult emergence. The female adults that were fed with MO began to lay eggs earlier, produced more eggs and lived longer than those that were fed with BB or WI. None of the female adults that were fed with BB laid eggs. The BB-fed female adults developed the lowest number of oocytes after one and three weeks of feeding. The female adults that were fed with WI and MO for one week developed similar numbers of oocytes. However, after three weeks the MO-fed female adults developed significantly more oocytes than WI-fed females. When female adults were first fed with MO for one week and then supplied with BB, subsequent ovarian development was strongly suppressed and the number of immature oocytes decreased. The results suggested that some immature oocytes degenerated. From these results it was concluded that MO was the most suitable adult host-plant, followed by WI and BB. It is possible that adults that emerge from BB trees may shift their host-plant during the adult stage in the field. [ABSTRACT FROM AUTHOR]

Adults of the white grub beetle Dasylepida ishigakiensis Niijima et Kinoshita (Coleoptera: Scarabaeidae) emerge from the soil around dusk for mating on subtropical islands. The present study examines the factors controlling the emergence of males in the laboratory. There are two steps involved. Standby behaviour (i.e. insect head appears at the soil surface) can be observed for several hours before the beetles actually emerge for mating. The standby behaviour is facilitated by warm conditions, although the proportion of standby individuals is influenced not only by the temperature on that day, but also by that on the previous day. Experiments in which beetles are exposed to photoperiod and thermoperiod combinations, in and out of phase, show that temperature is more important in inducing standby and emerging behaviour than light alone. For the second step, factors such as temperature, light and the presence of the female sex pheromone determine whether males will leave the standby position and emerge onto the ground. The female sex pheromone stimulates standby beetles to exhibit emerging and wing vibration behaviours, although the effect depends on when it is presented to beetles. Beetles burrow back into the soil; this behaviour is influenced by illumination and time of the day but not by temperature. The results suggest that D. ishigakiensis possesses a sophisticated mechanism controlling male emergence from the soil. [ABSTRACT FROM AUTHOR]

The present study investigates the emergence of adult white grub beetles Dasylepida ishigakiensis Niijima et Kinoshita (Coleoptera: Scrabaeidae) from soil as well as their burrowing behaviours. ‘Standby behaviour’ (i.e. adults come to the soil surface where they expose their heads) is shown in the field and, along with emergence behaviour, is entrained by LD photocycles. These 24-h rhythms persist after transfer to continuous light conditions for 2 days. By contrast, beetles transferred from LD photocycles to continuous dark conditions fail to show standby behaviour; thus, it appears to be manifested only in the presence of illumination. Under dark conditions, beetles emerge completely from the soil directly at the time when standby behaviour is otherwise expected to occur. Emerged adults then burrow back into the soil before dawn. Virgin and mated males, as well as virgin females, which are expected to emerge from the soil for mating on later evenings, burrow to a relatively shallow depth (<2 cm), whereas mated females burrow deeper (2–10 cm). Soil properties such as moisture, grain size, topography and temperature influence the burrowing behaviour and the depths that the beetles reach. [ABSTRACT FROM AUTHOR]

The white grub Dasylepida ishigakiensis has a 2-year life cycle and spends approximately 9 months as a nonfeeding larva, pupa and adult on a subtropical island. Evidence is presented indicating that this beetle has two diapauses that appear to synchronize this long life cycle with the seasons. Larvae exposed to 20, 22.5, 25 and 27.5 °C late in the third (last) stadium pupate rapidly except for some individuals kept at the highest temperature. The latter pupate upon transfer to 22.5 °C, indicating that larval diapause is maintained at high temperature but terminates upon transfer to a lower temperature. Pupal development is directly temperature-dependent in the range 20–30 °C. Adults develop reproductive organs (i.e. the ovary in females and the seminal vesicles and accessory glands in males) rapidly at 15 and 20 °C, whereas those kept at 25 °C take a long time to do so. Ovarian development is completely suppressed at 30 °C but initiated upon transfer to 20 °C. In the laboratory, males with well-developed reproductive organs mate even with sexually immature females , whereas females with undeveloped ovaries show no sexual behaviour. Although the two diapauses of this species are thermally regulated (i.e. a characteristic commonly expressed by insects in summer diapause), adults of this beetle emerge from pupae late in the autumn and remain in the soil for 2 months. Adult diapause effectively serves to synchronize the time of sexual maturation with the coldest month of the year. [ABSTRACT FROM AUTHOR]

Abstract: The ether extract of the females of white-spotted longicorn beetle Anoplophora malasiaca showed activity as contact sex pheromone to males. The extract was fractionated, and a pheromonal activity was revealed only when three fractions; n-hexane, n-hexane/EtOAc 9:1, and EtOAc were blended. The relative structures of gomadalactone A, B, and C, three active components isolated from the EtOAc fraction, were determined by spectroscopic studies to be (1S ∗,4R ∗,5S ∗)-5-hydroxy-4-[(E)-7-hydroxy-4-methylhept-3-enyl]-4,8-dimethyl-3-oxabicyclo[3.3.0]octan-7-en-2,6-dione, (1R ∗,4R ∗,5R ∗)-5-hydroxy-4-[(E)-7-hydroxy-4-methylhept-3-enyl]-4,8-dimethyl-3-oxabicyclo[3.3.0]octan-7-en-2,6-dione, and (1S ∗,4R ∗,5S ∗,8S ∗)-5-hydroxy-4-[(E)-7-hydroxy-4-methylhept-3-enyl]-4,8-dimethyl-3-oxabicyclo[3.3.0]octan-2,6-dione, respectively. [Copyright &y& Elsevier]

Focuses on sex pheromone and related compounds in the Ishigaki and Okinawa strains of the tussock moth Orgyia postica (Walker). Discovery of two distinct electroantennographycally active components, A and B, and a weakly active component C in a solvent extract from virgin females of the Ishigaki strain of the tussock moth; Finding of components A, B, and C in the extract of the females at 4.0, 0.5, and 4.0 ng/female respectively; Confirmation that the attractant pheromone of O. postica of the Ishigaki strain is also (11S,12S)-1; Discussion of the attractiveness of the components to the males on both Japanese islands in the context of the activity and possible evolution of pheromonal polymorphism in the species.