* Japanese name: Miyama-Karasuageha
* Scientific name: Papilio maackii
* Description: Widely held to be one of the most beautiful butterflies in Japan, the Alpine black swallowtail has a wing span of 38-75 mm and is covered in iridescent green or blue scales. Males have a green metallic shimmer to the wings. Females, which are bigger than males, are more blue-toned.
* Where to find them: Widespread across Japan from Hokkaido to Kyushu, the Alpine black’s flying season is from March to October. The prefix of the Japanese name, miyama, means “deep forest,” but the Alpine black can be found even at the edges of forests, especially near azalea bushes. It can also be found in grasslands, and in lowlands and on the coast, if there is grass present. There are usually two broods of Alpine blacks a year, the first in April-May, the second in July-August. Butterflies in the summer brood are larger.
* Food: Their favorite food is the nectar of mikan trees, and other fruit trees in the mikan family, such as mandarin. They also drink nectar from azaleas.
* Special features: Like other swallowtail butterflies, Alpine blacks will congregate in large groups. The behavior (called “hilltopping”) may be related to mate selection, as most of the females who group are “virgins.” Females that have already mated are not usually found in the groups. Mating partners are decided after an elaborate courtship dance. The male then grasps the female and transfers a package of sperm called a spermatophore. If the pair are disturbed during transfer, they may take to the wing, flying in tandem, joined at the genitals. Once the male has copulated with a female, he seals her genital opening with a mating plug, called a sphragis. This prevents another male from mating with her and protects his genetic investment.
In a time of both misinformation and too much information, quality journalism is more crucial than ever.
By subscribing, you can help us get the story right.