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The sap beetle Phenolia（Lasiodites）picta（MacLeay）（Coleoptera: Nitidulidae）is widely distributed in Asia, Australia, and Africa, but its basic biology has not been studied. In the present study, the seasonal prevalence of P.（L.） picta was investigated using banana bait traps in two regions, Minabe and Arida, Wakayama Prefecture, Japan, from April to October 2015 and 2016. Adults of P.（L.）picta occurred from late April–late October in Minabe, and late April–early September in Arida, respectively. The presence of larvae was observed twice in May–July and August–October in Minabe, but only once in May–July in Arida. These results imply that P.（L.）picta is a bivoltine in Minabe. The beetles oviposit in leaf mold, and a successful artificial rearing method was established using banana fruit and leaf mold. The effects of long and short photoperiods（long photoperiod, 14.5L:9.5D; short photoperiod, 10L:14D）on the ovarian development of females during ‘larval and pupal’ and ‘adult’ stages, respectively, were also studied in the laboratory. Females reared with a long photoperiod across all stages had significantly higher percentages of ovarian development（77.3%）than those reared with a short photoperiod during either ‘larval and pupal’ stages（20.0%）or ‘adult’ stages（35.0%). [ABSTRACT FROM AUTHOR]

A flightless strain of the ladybird beetle, Harmonia axyridis （Pallas ）（Coleoptera: Coccinellidae）, has been developed by artificial selection to enhance colonization. Colonization can also be facilitated by supplementary foods such as brine shrimp Artemia salina（L.） （Anostraca: Artemiidae）. Hence, we conducted a two-choice feeding test using cotton aphid, Aphis gossypii Glover, and brine shrimp. Interestingly, irrespective of whether the beetle had fed on brine shrimp or cotton aphids or neither of them before the experiment, they preferred the aphids over brine shrimp as their first choice. This suggests that even if the beetle consumes brine shrimp before it encounters cotton aphid, its preference for aphids remains unchanged. [ABSTRACT FROM AUTHOR]

The sap beetle, Phenolia（Lasiodites）picta（MacLeay）（Coleoptera: Nitidulidae）, is a pest that feeds on fallen Japanese apricots（Prunus mume）. Understanding the spatial distribution and migration patterns of adults should contribute to developing sophisticated management methods for this species. We counted the number of adult beetles on each fallen ripe apricot in an orchard in early summer in 2015 and 2016. Then we calculated Morisita's I δ index, which is an index of the distribution pattern without an association with density; it was 1.31 for females, 0.62 for males, and 1.15 for both sexes. These scores suggest that females and males have aggregated and uniform distributions, respectively. To examine if they used sexual or aggregation pheromones that can affect their distribution patterns, we tested the olfactory responses of each sex to food in plastic containers and to other individuals in a Y-tube olfactometer. Males were significantly attracted to females, while females showed a stronger response to food than to males. These results suggest that the sexual differences in the demands for food and mating partners cause the different distribution patterns in the field. [ABSTRACT FROM AUTHOR]

We demonstrate that vibrations carried in a food substrate induced escape behavior in the larvae of the sap beetle pest, Phenolia （Lasiodite ） picta （MacLeay ）（Coleoptera: Nitidulidae ）, which infests Japanese apricot fruits. Accelerations of continuous vibrations from 8 to 32 m/s2 at a frequency of 120 Hz within 30 min induced escape behavior in 60% of larvae. Pulsed vibrations of 1-s duration at intervals from 1 to 29 s induced escape behavior in 40-50% of larvae at 120 Hz and 8 or 16 m/s2. Our findings suggest that the application of vibrations to a food substrate has a potential for removing larvae from the food by inducing escape behavior. [ABSTRACT FROM AUTHOR]

The olive weevil, Pimelocerus perforatus（Roelofs）（Coleoptera: Curculionidae）, is a serious pest of olive cultivation in Japan. Although male and female adults of weevils are generally very similar, we established a simple method for discriminating the sex of olive weevil adults based on external morphology. We found that the first through fourth abdominal ventrites of the females were longer than those of the males, while the fifth abdominal ventrite was shorter. Moreover, the length of the lateral margin of the second abdominal ventrite was markedly different between the sexes. As a result, the ratio of the medial length of the fifth abdominal ventrite to the lateral margin length of the second abdominal ventrite was distinct between the sexes in both wild and laboratory-reared populations of P. perforatus, i.e., the ratio was larger than 0.60–0.65 in females but smaller in males. In addition to this characteristic, the structure of the medial part of the first abdominal ventrite differed between the sexes: it was depressed in the middle in males but inflated in the middle in females. Based on these morphological differences, males and females of the olive weevil were successively discriminated from each other. [ABSTRACT FROM AUTHOR]