Daily activity of adults of the small white butterfly, Pieris rapae crucivora Boisduval, was observed for 3 days under 14L-10D at 25-28℃ in a room (290 cm×320 cm×240 cm in height) illuminated about 2, 000 lx in light intensity at the center of the floor. We conducted 3 series of experiments : 10 females (Female group), 10 males (Male one), and 5 females and 5 males (Male-female one) were released in the room, respectively. They were active between 2 and 12 hours after the light-on in all groups, and daily activities of flight and foraging behavior were unimodal with a main peak at 5 to 9 hours after the light-on. Male butterflies of Male group tended to spend more time in flying than those of Male-female group, and the duration of female-searching flight of males was longer at the first half of photophase irrespective of groups. Females repeated short-term flights in Male-female group, while those in Female group tended to perch longer on plants throughout the photophase. Oviposition was observed frequently at the first half of photophase irrespective of groups, and oviposition and foraging behavior showed the second peak 2 hours before the light-off in Male-female group. The flutter response of males was frequently observed at the second half of photophase in Male group, while the response was few in Male-female group. These results demonstrate that the daily activity of P. rapae crucivora adults shows a daily periodicity under a constant temperature and photoperiodic condition, but suggest that it changes with inter/intra-sexual interferences.

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The adult activity and reproductive behavior of the plum moth Illiberis rotundata Jordan were investigated. Illiberis rotundata is univoltine and adults emerge from May to June in western Japan. Most adults emerged early in the morning especially within 2 hours after the beginning of the light phase under the laboratory conditions. Sex ratio at emergence was approximately 0.5. Females lived for 21.1±4.5 days (Mean±SD) and males lived for 24.0±5.4 days in the laboratory, taking only water. In the field, mating behavior was mainly observed in the afternoon. Females showed a characteristic calling posture as reported in other Procridinae species. Pair-bonds usually continued until the following noon, while some were ended even two or more days after (Median=21 h 57 m, Qr=1 h 57 m). Females copulated and oviposited repeatedly. The mean number of copulation was 7.1±4.5 (range : 2-16) under the experimental conditions. Oviposition was observed during the afternoon. The number of eggs that females deposited within a day decreased slowly. Fecundity, fertility and oviposition period of females which mated freely were 563.8±150.6 eggs, 80.6±17.8% and 11.9±3.1 days, respectively. We discussed the adaptive significance of their long copulation period, comparing them with those of other Lepidoptera.

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Present status on the systematics of the weevil genus Sphinxis Roelofs is reviewed for taxonomy, systematic position, distribution and biology. Several suggestions respect to phylogenetic relationships with related taxa and their biogeography are presented for future studies and surveys.

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The geographic variation in body size of an insect species may reflect not only differential adaptation to local climatic conditions but also evolutionary consequences of interaction with closely related species. Thus, both intra- and interspecific body size variations need to be analyzed to understand evolutionary significance of geographic pattern of body size variation in a group of closely related species. Here, we introduce geographic patterns of intra- and interspecific body size variation in two groups of carabid beetles in Japan, Leptocarabus and Ohomopterus (the subtribe Carabina, Carabidae) and discuss the possible factors leading to the observed patterns. Body size of a species generally decreases with decreasing warmth of the habitat (the converse of the Bergmann's rule). However, coexisting related species at sympatric zones show separation in body size, leading to deviation from overall clinal trend of body size variation within species. Probably, interspecific interaction through reproductive interference at the secondary contacts has played a role in determining the combination of species that could coexist or affected the body size differentiation per se.

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