A new agriine flesh fly, Goniophyto horii sp. nov., is described and keyed. Male genitalia and abdominal patterns are illustrated. Head profiles of G. boninensis Lopes and the new species are also figured for a practical identification.

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Improved methods for isolation of bacteria from apparently healthy mosquitoes and for demonstration of bacterial hemolysin production are precisely described. Several hemolytic bacteria were isolated from blood-fed mosquitoes, Aedes vexans nipponii and Aedes albopictus. Among them Bacillus spp. were the predominant in Ae. vexans nipponii. No Bacillus sp. was isolated from Ae. albopictus. No hemolytic bacteria except one strain of Serratia marcescens was isolated from Ae. albopictus concomitantly captured with Ae. vexans nipponii. Bacillus spp. isolated from Ae. vexans nipponii were found to produce hemolysins which exert hemolytic activity on rabbit, sheep and mouse erythrocytes. The molecular weights of these hemolysins were instantly estimated in situ on a slab for SDS-polyacrylamide gel electrophoresis (PAGE). These bacilli might be indigenous bacteria to mosquitoes rather than transient contaminants although the number of isolated bacilli was small.

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We examined the susceptibility of 4 species of adult house-invading bugs, Halyomorpha mista, Menida scotti, Lygaeus equestris and Urochela quadrinotata, to seven insecticides including three pyrethroides (cyphenothrin, phenothrin, permethrin), three organophosphates (fenthion, fenitrothion, diazinon) and one carbamate (propoxur) by contact methods. The tested pyrethroides were effective against all bug species. Especially, cyphenothrin was superior to the other chemicals both in fast-acting property and residual activity. Propoxur also showed considerable fastacting property and residual activity. On the other hand, organophosphates had little insecticidal activity under these experimental conditions.

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Inhibitory effects of two JHAs, pyriproxyfen and methoprene, on embryonic and larval development of the cat flea, Ctenocephalides felis, were determined by laboratory test. The inhibitory effects of the JHA on cocoon formation and larval-adult development when incorporated into the larval-rearing media of 1- to 3-day-old larvae were investigated. The IC_<50> values of pyriproxyfen were 0.0056ppm for cocoon formation and 0.00017ppm for larval-adult development, while the IC_<50> values of methoprene were 0.014 and 0.00032ppm, respectively. The ovicidal effects were observed when flea eggs within 24-hr-old were exposed continuously on filter paper treated with pyriproxyfen or methoprene, showing that the ID_<50> were 0.045 and 0.182μg/(cm)^2,respectively. Adult fleas were exposed to pyriproxyfen, then fed on a cat to investigate the ovicidal effect on flea eggs. The egg hatching was inhibited immediately. The partial inhibition (more than 50% inhibition) of egg hatching lasted for six days after treatment. The inhibitory effects of pyriproxyfen on egg hatching when treated on the fur of cats at dosages of 4 and 12mg per cat were investigated. The treatment at the lower dosage completely inhibited the egg hatching for 11 days and at the higher dosage for 18 days. In the latter case, the percentage of hatching was considerably less than that of the control throughout the 2 months after treatment.

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Cockroaches inhabiting in an underground shopping arcade in Osaka were investigated by using bait traps, and their susceptibility to insecticides were assessed by a topical application method. In the underground arcade, dominant species were Blattella germanica and Periplaneta brunnea accompanied by a small number of P. fuliginosa. The average number captured in the restaurant area of the arcade was almost equivalent between the dominant two species (1-2 roaches/(day・trap)). While B. germanica was dominant at cafe restaurants and Western style restaurants, P. brunnea was major at Japanese restaurants, Japanese pubs and sushi shops. The similar habitat preference was observed in the food store area, which had continuous floor and constant temperature and humidity among the shops. This habitat segregation has been basically unchanged during the 10 years of monitoring. It is supposed that one of the reasons of the habitat preference is originated from some difference of chemical factors in the food or food materials. In B. germanica, LD_<50> values for fenitrothion, pyrethrins and d-trans-permethrin had a tendency to increase gradually during the 10 years. All the final R/S ratio, however, still belonged to a low level. Against the P. brunnea, while LD_<50> value for fenitrothion was almost constant throughout the monitoring period, those for the two pyrethroids increased and, especially for d-trans-permethrin, the final resistance level was supposed to be of a moderate rank. According to these results, the current spray program in this field, multiple application of organophosphates (e.g. fenitrothion) and pyrethroids (e.g. permethrin), is considered an effective measure to suppress the population density of B. germanica as well as to prevent the development of their high resistance to insecticides. Against P. brunnea, however, it is suggested that successive monitoring studies should be necessary to watch the effectiveness of insecticides, particularly for synthetic pyrethroids.

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The fauna and distribution of blackflies (Diptera : Simuliidae) in Shiga Prefecture were investigated through our collection of larvae and pupae. The survey was conducted at 41 sites in November of 1986. A total of 16 species comprising 963 pupae and 3,541 larvae were captured from 36 sites. Five species, Simulium quinquestriatum, S. nikkoense, S. ogatai, S. rufibasis and S. mie were newly recorded from this prefecture. The predominant species was S. bidentatum (34.3%), followed by S. aokii (17.7%), S. japonicum (11.5%) and S. uchidai (11.5%). Simulium japonicum was collected in the mountain district of the north and western part of the prefecture. Simulium uchidai and S. bidentatum were distributed widely in Shiga Prefecture, and especially, S. aokii was abundant in the middle and northern part of the prefecture.

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The fauna and distribution of the blackflies in Hyogo Prefecture were investigated by collecting larvae and pupae stages of flies from streams and adults flying around the collectors in 79 localities in the spring of 1990. A total of 13,483 larvae, 1,761 pupae and 11 adults belonging to 2 genera and 23 species, 5 of which were unidentified, were collected at 71 sites. Eight known species of 2 genera, Prosimulium (Prosimulium) yezoense, Simulium (Nevermannia) konoi, S. (N.) subcostatum, S. (Gomphostilbia) ogatai, S. (Gnus) kisoense, S. (Simulium) japonicum, S. (S.) kawamurae and S. (S.) suzukii were newly recorded from Hyogo Prefecture. The predominant species was S. (S.) japonicum (28.4%), followed by S. (Odagmia) bidentatum (26.2%), S. (N.) uchidai (17.4%) and S. (O.) aokii (12.5%). The most widely distributed species was S. (S.) japonicum (54 sites), followed by S. (O.) bidentatum (49 sites), S. (N.) uchidai (43 sites), S. (S.) rufibasis (30 sites), S. (N.) subcostatum (27 sites) and S. (O.) aokii (26 sites).

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The Rickettsia tsutsugamushi (Rt)-DNA was detected and classified by polymerase chain reaction from larvae of an infected laboratory colony of Leptotrombidium pallidum. Rt-DNAs were detected in 6 of 14 engorged larvae (42.9%). Although Kawasaki, Karp・Kawasaki, Karp・Kawasaki・Kuroki, and unidentified Rt-DNA were detected from the infected larvae, only the Karp type was found by PCR in blood clots of a mouse attached with those mites used for Rt detection and in those of mice up to the 4th passage.

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The chironomid midges emerged during the winter season were investigated by light and emergence traps at the middle reaches of the Kiso River from November 1988 to March 1989. Fourteen genera and 19 species were identified. The most dominant species, Hydrobaenus kondoi Saether 1989,was especially abundant in midwinter.

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[in Japanese]

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Seasonal changes and the age composition of the roof rat, Rattus rattus L., were investigated in a building in Tokyo. a total of 591 rats were captured by glue traps in a 1-year period. Fifty-one point six percent of the rats was under 30 days old (95% confidence limit : 19-47 days) and 87.6% was under 60 days (95% confidence limit : 37-98 days). Age composition was older in October, January and February than in other months, and the population decreased from December to January and from October to November, and increased from July to August and from November to December. Continuous breeding was observed throughout the year, but the frequency fluctuated in a building with warm and constant temperature.

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Sexual mosaics were found in four adult Japanese blackflies, i.e., one Simulium aokii (Takahasi, 1941) and three S. bidentatum (Shiraki, 1935), all collected from a cattle shed in Shizuoka Prefecture. They were classified into two categories, i.e., bilateral and antero-posterior types of gynandromorph.

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