We found an individual of pselaphine beetle, Articerodes kurosawai Nomura, endemic to Ogasawara Islands, from a nest of the ant species, Nylanderia (=Paratrechina) ogasawarensis Terayama, in Haha-jima Island of the Ogasawara Islands, Tokyo, Japan. The beetle species was collected not only from N. ogasawarensis but also from N. amia Forel in Ani-jima Island of the Ogasawara Islands. The individuals of beetle that we collected were not attacked by both ant species in their nests, suggesting that the pselaphine is associated with the genus Nylanderia. Recent rapid rise of colonization of invasive ant species to the Ogasawara Islands may have negative effects on the distribution of the rare myrmecophilous beetles.

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Based on the first observation date of calling sounds and the daily mean temperature recorded by the meteorological observatory, adult population fluctuation of a cicada species,Cryptotympana facialis (Walker), for 36 years (1976-2011) was estimated in Osaka City. The population of this cicada species increased in the early 1980s, and has retained its high level since then. The periodicity could not clearly be detected in the population fluctuation pattern.

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Shikoku, the smallest main island of Japan, has a broad range of natural vegetations from hill forest to subalpine forest. It retains natural forests in small and scattered patches and most of natural vegetations have been replaced with plantations or orchards of economically important trees and agricultural fields. I review here geographic distribution of phytophagous flies, Tephritidae (Diptera), in Shikoku and discuss how vegetational differences in Shikoku affect tephritid species assemblages. Seventy-nine species, of which 11 are new to Shikoku, are recorded, based on published data and examination of supplementary specimens. They are estimated to represent more than 90% of the tephritid fauna in Shikoku. Tephritid flies are distributed over a broad range of natural and secondary vegetations. The results of the Non-metrical Multidimentional Scaling, using the presence-absence data of tephritid species from 48 collection localities, indicate that tephritid assemblages are affected by differences in natural, primary vegetations rather than by those in secondary, modified vegetations. Alsangelisca takeuchii (Ito), Calosphenisca aliquantula (Ito) and Campiglossa jugosa (Ito) have been found only in the montane and subalpine natural forests of Mts. Ishiduchi and Takashiro, as the southernmost, isolated populations in their distribution ranges. Conserving natural forests of these areas is recommended for maintaining the species diversity of tephritid flies in Shikoku.

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Bioindicators are important for evaluating desired outcomes accurately and inexpensively, such as increases in biological diversity. Reasonable baselines are needed to monitor changes in Japanese Satoyama landscapes. At each locality, a baseline density should be determined for every bioindicator species in relation to both surrounding land-use and monitoring method. The Japanese horned beetle Trypoxylus dichotomus septentrionalis is one of the most emblematic and charismatic species in the Satoyama landscape. The number of beetles attracted to fixed light sources was surveyed every day except for rainy days from 2004 to 2011 at a location in the Izu Peninsula. Annual net replacement rate (N_t+1/N_t) was significantly inversely related to the number of beetles collected in the previous year (N_t) (R²=0.601, P=0.0406). Populations fluctuated around an equilibrium value of 73, and the deviations from the equilibrium value were related to the mean monthly temperature in June (T) when the beetles were pupae or teneral adults. A high negative correlation (R²=0.4570, P=0.0657) between N_t and T was observed. Female body length, but not male's, was mainly determined by the mean monthly temperature in April(R²=0.8470, P=0.0033). A warm early spring seemed to encourage an earlier development of overwintered larvae and contribute to the production of larger adult females. Hot summers negatively affected the number of beetles, but the density dependent population processes provides a resilience that may prevent the beetle from an ever more rapid decline. The equilibrium density of a bioindicator species could be used as a baseline density in biodiversity conservation projects.

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Nesting biology, annual life cycle and sociality of Lasioglossum occidens were studied in a greenhouse and at the field in 2004. The results proved that the species is a bivoltine and basically solitary bee. The brood rearing period of the overwintered (G₀) and first (G₁) generation started from early May to mid June and early July to mid August, respectively. The nests are of the typical branched halictine nest pattern, each cell connected with the main burrow by means of the lateral burrow. In the greenhouse, one multi-female nest, composed of 2 cohabitants of the same generation, together with 13 and 9 solitary nests was discovered in G₀ and G₁, respectively. Task allocation between cohabitants in this multi-female nest was relatively distinct, so far as foraging activity. The occurrence of rudimentary caste was also discussed.

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To elucidate the ecological significance of worker polymorphism in ants, quantitative analyses were conducted of the division of labor system and phenotypic plasticity in Pheidole noda exhibiting dimorphism (major and minor workers) in the worker caste. In the laboratory, we examined the numbers and behavior of major and minor workers and their modes in a foraging area with emplaced a whole prey cricket or minced cricket. When whole crickets were provided in the foraging area, many major workers appeared and worked mostly at prey dismantlement. Minor workers mainly transported the crickets without dismantling them. In colonies comprising only a queen and minor workers, we observed several times that the queen appeared in the foraging area to dismantle whole crickets. When subcolonies of three types, i.e., those with 20 minor workers and a major worker with a distended abdomen, 20 minor workers and a major worker with a normal-sized abdomen, and 21 minor workers, were kept under a starving condition, the survival period of minor workers was significantly longer in subcolonies with a major worker having a distended abdomen than in the others. That result suggests that major workers with a distended abdomen have the function of nutrition storage. The major worker ratio was not significantly different between subcolonies that had been fed only with minced crickets for 63 days and those that had been fed only with whole crickets during the same period, but the major worker head size was significantly larger in colonies fed whole crickets than in those fed with minced ones. These results indicate that P. noda changes the major worker phenotype, not the ratio, in response to different foraging requirements for the subcaste.

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A dismantling show using exterminated wasp nests was designed and practiced as a department of the museum festival. It was carried out smoothly under the good partnership between the Kurashiki Museum of Natural History and the pest control company. This interesting experimental trial produced merits for both of them. That is to say, a dismantling show of wasp nests is very effective to attract citizens' interest to natural history museums. On the other hand, the pest control company can offer exterminated wasp nests, which are unnecessary for their company or customer in many cases, for the effective educational campaign. It is ideal that the event using wasp nest will be planned in September and afterwards because event sponsor tend to obtain the enough expanded their nests with many individuals or caste (queen, male and worker). Additionally, some other ways of utilizing exterminated wasp are introduced.

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My website "Carabine ground beetles of Japan & Shiga Prefecture"(http://wwwlbm.go.jp/emuseum/zukan/osamushi/index.html) was awarded the Akitsu Prize 2008 by the Japanese Entomological Society. The site is deivided into four categories: 1) a primer on carabine ground beetles; 2) research methods for carabine ground beetles; 3) Japanese carabine ground beetles; and 4) carabine ground beetles of Shiga Prefecture.

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