2007 年 2007 巻 54 号 p. 165-172
Distribution of the alfalfa weevil, Hypera postica (Gyllenhal)(Coleoptera: Curculionidae) was surveyed at 179 sites of 16 prefectures in Central and Northern Honshu Island, Japan in the spring of 2006. H. postica was recorded for the first time in Toyama, Ishikawa, Fukui, Yamanashi, and Nagano Prefectures, but could not be found in Aomori, Iwate, Miyagi, Akita, Yamagata, Fukushima, and Niigata Prefectures. In Ibaraki and Tochigi Prefectures, H. postica extended its distribution range about 60km northward from the spring of 2003 to the spring of 2006. H. postica was distributed widely in the plains of Saitama and Gunma Prefectures where the weevil has already been found.