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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]

The use of pheromones to disrupt mating behaviours is perhaps the most promising method for controlling the sugarcane pest Dasylepida ishigakiensis Niijima et Kinoshita, also known as the white grub beetle. Herein, based on laboratory observations of mating, oviposition and hatching behaviours in the white grub beetle, we suggest guidelines for the timing and length of sex-pheromone release in the field. In the present study, we collected virgin female adults early in the mating season (4 February) in sugarcane fields in Okinawa, Japan and mated them in the laboratory after different time intervals with males collected at the same time. We investigated the effects of delayed mating on mating success, timing of oviposition, female longevity after mating and progeny hatchability. Mating success – defined as the proportion of mated females that produced progeny – and hatchability were not significantly affected by mating delays of less than 31 days, although further delays dramatically decreased these parameters. Female life span and the time between mating and oviposition were unaffected by mating delay. Similar results were obtained for laboratory-reared adults mated on day 45, 60 or 80 after adult emergence. Based on these findings, we propose that releasing synthetic sex pheromones between mid-January (i.e. shortly before the start of the mating season) and late March would be optimal for disrupting the mating behaviours of this beetle in the field. [ABSTRACT FROM PUBLISHER]

The subtropical scarab beetle, Dasylepida ishigakiensis, has a two-year life cycle. This study showed the time of adult emergence from the soil relative to the time of dusk and the presence of the female sex pheromone. Beetles collected on Miyako Island were transported to Tsukuba where they were immediately placed under natural day lengths in February. They exhibited two emergence peaks that corresponded to the times of dusk in Tsukuba and on the island, respectively. Males emerged precociously if a lure containing synthetic female sex pheromone was placed in their container, whereas the females' behavior was unaffected. Previous observations that mated females dig deeper in the soil than virgin females, males or mated males were confirmed. To explore the underlying mechanism controlling the behavioral change associated with mating, liquid material derived from the male accessory glands, seminal vesicles and female bursa copulatrix was injected into beetles, but without any significant influence on burrowing behavior. No significant influence was also observed in beetles injected with anisomycin, an inhibitor of protein synthesis related to memory in other animals. [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]

Olfactory and visual cues were shown to mediate short-distance orientation in Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae). In a laboratory test, more than 80% (n = 42) of males walked straight upward when presented with an untreated surface with a 75° slope. When a freshly killed female was fixed at a short distance (10 cm ahead and 5 cm to left/right) from the starting point, 50% of males (n = 30) were oriented toward the female before direct contact. Similar behavioural responses were observed when female extract was directly applied to the slope or to a glass rod model fixed on the slope. When black, white, and transparent coloured rods with the extract were presented, the orientation response was significantly greater for black than to white and transparent rods, to which only a negligible response was observed. [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]