抄録
In the present paper, the current status of distribution of Zizina otis is presented, and a method for conservation of the species is proposed. Although Z otis has been recorded from 8 prefectures in eastern Japan, it became extinct in 5 prefectures until 2002. The eastern Japan population of this species has been in danger of extinction. It is suggested by the study in the riversides of the Kamanashi and the Fuefuki Rivers in Yamanashi Prefecture that the reduction of the population of this species is due to the reduction of the host-plant colonies by periodical mowing and river improvement works. It would be effective that to fence host-plant colonies by net-fence through which Z. otis individuals can pass for protecting the plants from mowing and other disturbances. The geographical variations of coloration and shape of male genitalia of this species are also commented.
