Forty-nine Japanese species of Amblyseiinae, a subfamily of Phytoseiidae, are assigned to 10 genera, namely: Neoseiulus Hughes, Typhlodromips De Leon, Typhlodromalus Muma, Amblyseius Berlese, Euseius Wainstein, Proprioseiopsis Muma, Okiseius Ehara, Amblyseiulella Muma, Paraphytoseius Swirski and Shechter, and Indoseiulus Ehara. An annotated list of these species and keys to the genera and species are given, with redescription of Neoseiulus repletus (Wu and Li), recorded from Japan for the first time. Paraphytoseius urumanus (Ehara) differs from P. orientalis (Narayanan, Kaur and Ghai) in that leg IV is provided with five instead of four macrosetae.

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The distribution pattern of Aculops lycopersici (Massee) in a tomato leaf and method for estimating the density of the mite were examined. The distribution pattern of adults and nymphs was similar. About a half number of mite population infested leaflets and the other half petioles. Most of the mites infested the upper surface of the leaves. On petioles, the density of the mite was high at the posterior part. Mite numbers were large on leaflets near the stem. The percentage of the number of mite population on each part of the leaflet to the total number on whole leaf did not vary irrespective of the population density. On leaflets, the mite density was higher in the middle than periphery and also higher at the bottom than the top. However, the density became uniform in the leaflet when the density became high. From the distribution data obtained, a method for estimating the densities of mite population on whole leaf was proposed, i.e. mite numbers on the second and third leaflets and several parts of the petiole were counted.

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Two new species of the genus Tenuipalpus, T. mandraensis and T. kenos, are described and illustrated. These species are assigned to the T. annonae subgroup, T. caudatus group.

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We studied mitochondrial DNA variation in the Kanzawa spider mite, Tetranychus kanzawai, based on 705-bp sequences of the cytochrome oxidase subunit I (COI) gene from 23 strains. Fifty-two sites (7.4%) were polymorphic, but we did not find substitution saturation in this gene. Thus, this region was thought suitable for phylogeographic analysis at the intra-specific level. Maximum likelihood trees showed that all of the studied strains of T. kanzawai formed a single lineage. However, geographic and genetic distances were not significantly correlated. Thus, to obtain sufficient polymorphisms for phylogeographic analysis of T. kanzawai, the development of new primers to amplify more variable regions will be required.

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Hexane extracts derived from an unidentified Oulenzia sp. showed the alarm pheromone activity. The extract was composed of the following 10 compounds; tridecane, neral, pentadecane, dodecane, 3-hydroxybenzene-1,2-dicarbaldehyde, geranial, (Z)-7-pentadecene and 7-hydroxyphthalide in decreasing order together with two unknown compounds. After fractionation with a silica gel column, the active fraction consisted of a mixture of neral and geranial. Neral was found to show the activity, but geranial was not. Neral was, therefore, identified as the alarm pheromone of this species.

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Pesticide (six insecticides and 16 acaricides) susceptibility of populations of N. californicus (4 populations) and N. womersleyi (5 populations) was investigated to test the hypothesis that the recent species replacement between these two species was due to a change in pesticides used in orchards combined with a differential susceptibility of the two species to one or more of the new pesticides. Although the present results cannot provide a clear conclusion regarding factors responsible for the change in dominant phytoseiid, it was suggested, at this point, that none of the pesticides examined here seemed to have a decisive influence on the replacement of N. womersleyi by N. californicus.

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The spider mite, Tetranychus takafujii Ehara and Ohashi, a species found from Solanum nigrum L. in Kinki district in 2001, showed good performance on solanaceous plants such as S. nigrum, eggplant, sweet pepper and tomato. Females became the adults in 8.85 days (males in 8.25 days) and total egg production of copulated females was 190.7 on eggplant. The intrinsic rate of natural increase (r_m) of T. takafujii was 0.321/day on eggplant. Thus, the reproductive capacity of T. takafujii was higher than those of serious pest mites such as T. urticae and T. kanzawai.

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To know the seasonal occurrence of ixodid ticks, we collected them by flagging on vegetation in the woods (mostly natural forest) of Mt. Kanmuri-dake, Kagoshima Prefecture, southern Japan, at a monthly interval from August in 1997 to July in 1998. Flagging was done at three sites by two persons for 30 min. per site. A total of 9,141 ticks (5,625 larvae, 2,671 nymphs and 845 adults) were collected and all were identified to the species level. Among the nine identified species, Haemaphysalis flava, H. formosensis, H. longicornis, H. hystricis, H. kitaokai, Ixodes ovatus, I. nipponensis, I. turdus, Amblyomma testudinarium, the two Haemaphysalis species, H. flava and H. formosensis, dominated and their seasonal occurrence could be examined. Both species were collected nearly all year round, but the adult seasons differed between the two species; adult increased from late autumn to winter in the former species but appeared two times, autumn and spring, in the later.

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