Visual 'pinpoint' location associated with pheromonal cue in males of the black chafer Holotrichia loochooana loochooana (Coleoptera: Scarabaeidae)

Abstract

Females of the black chafer Holotrichia loochooana loochooana (Sawada) (Coleoptera: Scarabaeidae) release anthranilic acid, which functions as sex attractant pheromone for males and aggregation pheromone for females. When a white lure treated with anthranilic acid was placed next to an untreated black lure in the field, males were observed to make pinpoint landings significantly more frequently on the latter. When the distance between the two lures was increased from 0 to 20 cm, frequency of pinpoint landing onto the untreated black lures significantly decreased while that onto the treated white lures slightly increased. When the lures were further separated to 2.5-m intervals, males approached only to the treated lures regardless of the color but significantly more frequently landed on the black ones than on the white. These observations demonstrated that males locate and land on a female by visual cues after reaching the vicinity by olfaction.

Formulation of highly volatile pheromone of the white grub beetle Dasylepida ishigakiensis (Coleoptera: Scarabaeidae) to develop monitoring traps

“…D. ishigakiensis males are often observed to land on a female or very close to her before mating in the field (Arakaki et al, 2004). The importance of visual orientation has been demonstrated in the black chafer (Fukaya et al, 2006). These observations suggest that visual stimuli may be involved in the mating behavior of D. ishigakiensis; however, the results of the present study indicated that a visual target is not necessary to capture males with pheromone-baited traps.…”

Aggregation of the black chafer Holotrichia loochooana loochooana (Sawada) (Coleoptera: Scarabaeidae): Function of female pheromone and possible adaptive significance

“…6) or at a 5-cm interval at right angle to the wind (Fukaya et al, 2006), the males were observed to land equally on the two lures. This suggests that a female releasing a maximum amount of pheromone (hereafter, major female) would have an equal chance to attract a male when she takes a position near another major female.…”

“…The anthranilic acid attracts males , and causes them to land directly on a black or dark object, such as a female. In the process, the males switch orientation cues from olfactory to visual when they are around 15 to 20 cm from the pheromone source (Fukaya et al, 2004(Fukaya et al, , 2006.…”

“…Subsequently, we confirmed that the ratio of the sexes was biased toward females. Since the males change from olfactory to visual orientation cues once they come near the pheromone source (Fukaya et al, 2006), this female-biased sex ratio and the non-uniformity in the female pheromone release led us to draw the following hypotheses: A female that releases little or no pheromone may increase its chances of getting a mate if it takes a position near one or more females that had released a large amount of pheromone. If the late-arriving females also release their pheromone within the pheromone plume from the females that arrived earlier, the total attractiveness of the plume to males will increase .…”

A Pheromone-Based Trapping System for Monitoring the Population of Cosmopolites Sordidus (Germar) (Coleoptera: Curculionidae)

“…Hidaka (1972) reported the necessity of visual stimuli in addition to pheromones to attract Hyphantria cunea (Drury) (Lepidoptera: Arctiidae) males, and Carlton and Cardé (1990) noticed that Lymantria dispar (L.) (Lepidoptera: Lymantridae) males also used visual cues after landing on females. More recently, Fukaya et al (2006) demonstrated the importance of visual stimulus (black and gray sources) in combination with the female sex pheromone anthranilic acid for mate location in the black chafer, Holotrichia loochooana loochooana (Coleoptera: Scarabaeidae). Our results show that C. sordidus relies exclusively on olfactory cues.…”