Hirokazu Sakamoto, a butterfly enthusiast from Higashi-Sumiyoshi Ward in the city of Osaka, has successfully bred more than 20 Gifu butterflies that have taken flight in the recent warm weather, catching the attention and admiration of his neighbors.

The wings of Gifu butterflies (Luehdorfia japonica) are similar to those of swallowtail butterflies in their vivid yellow pattern, but the former is distinguished by its bolder black stripes.

Sometimes called the "queen of spring," an adult Gifu lives only a week after its metamorphosis. Following a brief period bathing in sunshine, the adult male then takes gracefully to the air in search of female partners.

"How alluring are the butterflies, making their best effort in such a short lifespan," said the 75-year-old Sakamoto.

Gifu butterflies, known as "Gifu-cho" in Japanese, are endemic only to the foothills of Honshu.

After the eggs hatch in April, young caterpillars feed on wild ginger leaves that are perennial in the region. The caterpillar pupates after a month, then hibernates for another 10 in preparation for its emergence the following spring.

Since much of the butterfly's habitat has been destroyed by human activity, the Environment Ministry has classified the species as at risk of becoming endangered.

Surviving wild Gifu butterflies can be spotted in the Kansai region near Mount Katsuragi on the border of Osaka and Nara prefectures, and near Takedao in Hyogo Prefecture.