KOFU -- An Oomurasaki butterfly with both male and female characteristics on its wings was recently found at the Oomurasaki Center in Hokuto, Yamanashi Prefecture, a facility that breeds various species of insects.
This rare member of the species, which is the national butterfly of Japan, is called a gynandromorph. It is said to appear at a rate of only one among thousands to tens of thousands.
The center is scheduled to exhibit the specimen to the public starting Sept. 22.
The Oomurasaki butterfly is known as a great purple emperor in English. Its scientific name is Sasakia charonda.
The rare creature was discovered by 15-year-old Noi Maeshima, a first-year high school student in Fujimi, Nagano Prefecture. When Maeshima visited the center with relatives on July 18, he noticed the butterfly inside an indoor facility where about 2,000 butterflies were flying.
Its left wing was blue-violet, which is characteristic of males, and the right wing was brownish-red, which is typical of females.
Maeshima has been an avid insect collector since he was a little child. He thought it was definitely a gynandromorph, as he had seen an image in a book. He took numerous photos with his smartphone and notified the center after returning home.
Deputy head of the center Kazutaka Togashi searched for the butterfly with four staff members across the facility. After two days, they found the gynandromorph.
The butterfly was dried for about a month to turn it into a specimen. "I myself desperately wanted to see a real one," Togashi said.
According to Takashi Yagi, head of the Lepidopterological Society of Japan and a professor emeritus of Osaka Prefecture University, gynandromorphs are the result mainly of chromosome abnormalities when fertilized egg cells divide.
Center director Jiken Atobe said: "I've studied Oomurasaki butterflies for more than 40 years, but that was the first time that I saw a living gynandromorph. I was impressed by its beauty."
Read more from The Japan News at https://japannews.yomiuri.co.jp/
