Adults and eggs of five stored-product insects were exposed to low-oxygen atmospheres containing 0.1– 0.6, 0.6–1.3, and 1.2–3.1% oxygen in nitrogen at 20 and 30 ˚C and 70% relative humidity. The treatment periods were 2, 4, 7, 10, and 14 days. Adults and eggs of Sitophilus zeamais and Lasioderma serricorne were more tolerant of low-oxygen concentrations than those of Tribolium castaneum, Liposcelis bostrychophilus, and Plodia interpunctella. The present study showed S. zeamais and L. serricorne eggs respectively needed 7 and 14 days of treatment at 0.1–0.6% oxygen concentration and 30 ˚C to provide complete mortality.

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I investigated the seasonal patterns of the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae) by capturing them in pheromone traps placed outside residential buildings in Toride and Tsukuba, Ibaraki Prefecture, Japan. The survey was conducted over three years (2014 – 2016). The adult beetles were captured from May to November, peaking in June. In all of the one-year periods, the peak in Tsukuba was less distinct than that in Toride. The total numbers of beetles caught per year were 66, 56, and 144 in Toride, and 9, 7, and 11 in Tsukuba.

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I investigated development of Indian meal moth larvae, Plodia interpunctella (Lepidoptera: Pyralidae) on dried honeybee pollen and brown rice. Two first-instar larvae were placed on 3 g of food materials and were maintained at 25, 28, and 30 ˚C, 70% RH, and 16L 8D. I recorded their developmental period, emergence rate, and fresh adult weight. Larvae reared on dried honeybee pollen showed a faster developmental period at 25, 28, and 30 ˚C and higher fresh adult weight at 25 and 28 ˚C than those reared on brown rice. There were no differences in emergence rate between honeybee pollen and brown rice at 25 and 28 ˚C.

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An outbreak of the Eremocoris planus occurred in an apartment building in Tokyo. This is the second case of this species in the Kanto district after Chiba Prefecture, and the first record in Tokyo. Larva morphology is recorded.

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Adult numbers of the maize weevil, Sitophilus zeamais Motschulsky, were investigated using pheromone traps in five low-temperature grain storage warehouses on the Kanto Plain, Japan, for two years. Pheromone traps were placed in the storage rooms and working areas of each warehouse and replaced with new ones monthly. The efficacy of mass trapping of S. zeamais adults was tested in two of these warehouses. In each warehouse, 14 or 20 pheromone traps were also placed in the working areas from October to December and from March to May. In one warehouse, it seems that overwintering of S. zeamais in the warehouse might have led to an increase in the number of adults caught by the traps starting in spring. In one of the warehouses in which the efficacy of mass trapping was tested, the number of adults caught by monitoring traps was low during the monitoring period, and the number of adults caught by traps for mass trapping was also low. In the other warehouse, more than 100 adults were caught between October and December 2018, and more than 10 adults were captured in the other periods. The conditions under which the mass trapping is effective are discussed.

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