Mutilla mikado Cameron is an ectoparasitoid of bumblebees, occasionally causing a serious damage to the host colonies. The oviposition behavior was observed with Bombus diversus cocoons as the host, under uncontrolled air conditions from September to October, 2003 in Ohtawara, Tochigi, central Japan. Prior to oviposition, the female mutillid examined host cocoons with the antennae and bit the upper side of a selected cocoon with her mandibles to fix her body firmly. Thrusting her sting into the cocoon, the mutillid paralyzed the host and laid an egg on it. The egg was always found on the host prepupae or pupae and lightly attached to the host body, not glued to it. Both prepupae and pupae were paralyzed before oviposition. Paralyzed hosts did not show any evidence of further development, but survived for a fairly long time, even if mutillid eggs were removed. The sting of the mutillid is about 4mm long and 0.1mm wide, slightly curving ventrally and flattened on both sides. A shallow groove descends along the ventral surface of the sting. The process of egg deposition to the host body in M. mikado is considered as follows. The female mutillid opens the sting valves after she has finished thrusting them into a host cocoon. Extending the sting, she probes around the host body with her sting tip and punctures the host to paralyze it. An egg is gradually discharged from her genital opening, and slides down along the shallow groove of the ventral surface of the sting onto the host body.

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Life cycle and seasonal change in within-habitat distribution pattern of the intertidal staphylinid beetle Bryothinusa algarum Sawada were surveyed in the Osaka Nanko Bird Sanctuary in Kinki district, Honshu, Japan, from May 2003 to April 2004. Quadrat counting and field observations have revealed that B. algarum has a univoltine life cycle in Osaka Bay area. Mean crowding (m^*) and the ratio of mean crowding to mean density (m^*/m-) were used for an analysis of the distribution pattern. The m^*/m- was higher than 1.0 almost throughout the season. It means that the species has a patchy distribution pattern. Distribution of the species became random slowly from May to July and aggregated after September. It suggests that individuals aggregate during hibernation.

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Ground beetles function as important predators of insect pests, and have been used as indicators of environmental change in agricultural fields. In this study, we captured ground beetles in an agricultural landscape that included paddy fields, pasture, orchards, and woodland, for the purpose of comparing the number of species and species diversity among vegetation types. In addition, the species composition of ground beetles was analyzed using detrended correspondence analysis (DCA). Forty species of carabids and brachinids were captured from May 2003 to January 2004. The subfamily Callistinae, which includes active predators of lepidopteran pests, was captured mainly in pasture and orchards. The subfamilies Zabrinae and Harpalinae, which contain many omnivorous species, were most abundant in paddy fields. Carabus yaconinus, which typically inhabits woodland, was also frequently captured in the orchard neighboring woodland. DCA revealed that the species composition of ground beetles was similar in paddy fields and pasture, as well as in orchard and woodland.

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Aphis fabae Scopoli has been considered a recent invader because two subspecies of this species were found after the end of 1980s from Japan. However, it is not certain whether A. fabae had occurred in Japan before then or not. To address this issue, old aphid collections were inspected, and literature was surveyed. As a result, I found some specimens that should be identified as A. fabae among the collections before the beginning of 1980s. Of the specimens, the two oldest collection data were as follows: Mt. Apoi, Hokkaido, ex Heracleum sp., 28. vi. 1967 and Nikko, Tochigi Pref., ex Cirsium sp., 6. x. 1967. These records indicate that A. fabae had occurred in Japan at least in 1960s. Literature survey showed that descriptions of the morphology of Aphis rumicis Linnaeus and its host records by S. Matsumura, R. Takahashi and O. Shinji in the early half of 1900s agreed partly or completely with those of A. fabae. This suggests that A. fabae had occurred in Japan of those days.

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Twenty-nine cases of injury caused by flea in Toyama Prefecture from 1973 to 2006 were reported based on the evidence of identification service by the Toyama Institute of Health. Causative flea species were Ctenocephalides canis (1 case), Ctenocephalides felis felis (22 cases), Ctenocephalides sp. (3 cases), Monopsyllus anisus (2 cases) and Nosopsyllus fasciatus (1 case). Most of injuries were of human infestation or flea appearance in the room. Other rare cases were contamination of C. f. felis into a commercial product, human infestation by M. anisus, and larvae of M. anisus as a nuisance pest.

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