The genus Cycloppia was revalidated from Processoppia and revised. A key and species list of its related genera were given. Three Japanese speces, C. simplex (Suzuki), C. restata (Aoki) and C. granulata spec. nov., became the only members of Cycloppia. New replacement name Rhaphoppia mihelcicana was given to Oppia mihelcici Hammer, 1968 which is a junior primary homonym of Oppia mihelcici Pérez-Iñigo, 1965.

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A new species of oribatid mite, Hermanniella todori sp. nov., was collected from forest litter and surface soil in the western part of Tokyo. The new species is distinguishable from other closely related species of Hermanniella by a pair of peculiar dorsal setae f₁, which are quite different in shape from the other dorsal setae.

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The attractiveness of food odor to the mould mite was demonstrated in the micro-locomotion compensator (MLC) as well as in a classical choice-chamber. The MLC has been developed for use in experiments on the orientation mechanisms of tiny animals. The positioning system of the MLC constantly returns a mite walking on a glass plate to the center of the apparatus by sliding the plate. A computer controlling the MLC logs the displacement of the plate, whose array defines the path of the mite. It also controls a micro solenoid-operated valve to generate odor cues in airflow over the mite. If the odor is generated by position in a virtual olfactory field created by the MLC, the mite would exert a similar olfactory response as in a real choice-chamber. In practice, odorous zones with attractant were defined on the glass plate in a checkered pattern, and the test animal was exposed to the odor while it stayed in the zones. Mites were effectively confined to the odorous zones in the virtual olfactory field, as well as in the real choice-chamber. The frequency of stays in the odorous zones positively correlated with the odor concentration to provide a reliable estimate of attractiveness using probit analysis.

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A new species of trombiculid mite, Doloisia uchikawai sp. nov., collected in Kagoshima and Oita Prefectures, Japan, is reported here with their morophological characteristics. It is closely related to D. okabei Sasa et al., 1952 and D. minamii Suzuki 1976, but distinguishable in the shape of scutum, sensillae, number of coxal setae and in standard measurements of scutum.

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Occurrence of the recently described spider mite, Tetranychus takafujii Ehara and Ohashi, on Solanum nigrum L. was confirmed in the urban areas of Osaka, Kyoto, Hyogo and Tokyo Prefectures. The mite overwintered at all stages, suggesting that it is a non-diapausing species. However, the survival rate of the mites during winter in the field was very low. These facts suggest that this species had invaded the Kinki district from tropical or subtropical zones. Nevertheless, the mites survived at least two winters in Kinki district from 2001 to 2003, and they may have established a population in the area.

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Two similar species of oribatid mites, Euphthiracarus foveolatus and E. cribrarius, have different distributions, with the former being endemic to Japan and the latter being a widespread Eurasian species that has not been reported from Japan. Recently the distinction between these species has become questionable, due to a mistake discovered in the original description. Also, new collections of E. foveolatus from Japan have shown it to be variable in morphology, and this variability overlaps in some ways with that of European populations of E. cribrarius.
In this paper, we examine the morphological variability of E. foveolatus and reconsider its distinctness from E. cribrarius, which seems to be its closest relative. Studied specimens of the latter were from Norway, the type country. Despite some overlapping characters, the Japanese and Norwegian specimens are distinguishable in two obvious ways. First is the ratio of lengths of aggenital setae (ag₁/ag₂); that of E. foveolatus is five or more times greater than the ratio in E. cribrarius. Second is that E. foveolatus lacks three leg setae that are present in E. cribrarius: one unnamed seta on tarsus II, v' on genu III and v' on genu IV. Thus, we feel these species are distinct and the names are not synonyms.

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