The mayfly genus Drunella is the most diverse genera in the family Ephemerellidae, and is found in lotic streams throughout East Asia and North America. The species D. ishiyamana is found widely throughout East Asia and their species concept has not been properly defined until recently. The D. ishiyamana species group was examined, and morphological and molecular evidence of a new species were uncovered. In this study Drunella punctata sp. nov. is formally described, mainly distinguished from D. ishiyamana by the lack of a notch in their median clypeal tubercle in their larval stage. Photographs, diagnosis, and descriptions of D. punctata are provided.

To understand the oviposition biology of arrowhead scale, Unaspis yanonensis (Kuwana) (Homoptera: Diaspididae), the longevity and fecundity of the overwintered females were examined at various temperatures (16, 20, 24, 28, and 32℃). The total fecundity increased with rising temperature, showed a maximum of 260.9 crawlers per female at 24℃, and then declined thereafter. Females showed a periodical oviposition activity. The 1st cycle fecundity was identified at all temperatures examined, and was not significantly different between 16 and 28℃. However, the 2nd cycle fecundity and later cycle fecundity were much lower at 16, 20, and 32℃ than those at 24 and 28℃. The pre-oviposition period ranged from 49.0 d at 16℃ to 19.7 d at 32℃, and was the shortest 19.4d at 28℃. The linear lines of mean development rates (1/mean pre-oviposition period) against temperatures provided the estimate of low-threshold temperature 8.7℃ for pre-oviposition stage and the thermal constant of 358.1 DD. The lower threshold temperature and thermal constant for the completion of U. yanonensis pre-oviposition period well predicted the first crawler occurrences in the fields.

This study was conducted to investigate the effect of combine crawler attaching slurry spreader on soil and growth of rye. The performance test at actual field was conducted to test for possibility of practical use. Field test of the slurry spreader was o

Legged locomotion has high mobility on irregular surfaces by touching the ground at discrete points. Inspired by the creature’s legged locomotion, legged robots have been developed to explore unstructured environments. In this paper, we propose a modular crawler that can easily adjust the number of legs for adapting the environment that the robot should move. One module has a pair of legs, so the number of legs can be adjusted by changing the number of modules. All legs are driven by a single driving motor for simple and compact design, so the driving axle of each module is connected by the universal joint. Universal joints between modules enable the body flexion for steering or overcoming higher obstacles. A prototype of crawler with three modules is built and the driving performance and the effect of module lifting on the ability to overcome obstacles are demonstrated by the experiments.