It is the only butterfly species under first-class national protection in my country. Why does the Swallowtail Butterfly rarely "come down to earth"?

Butterflies dance among flowers, nimble and beautiful. If we compare the beauty of butterflies, the "C" position must be the golden-spotted swallowtail butterfly. The dark green background is dotted with bright yellow spots, making the golden-spotted swallowtail butterfly unique in the butterfly family.

The Swallowtail Butterfly, known as the "national butterfly", ranks first among the world's eight most precious butterflies. It is the only butterfly species under first-class national protection in my country. Its numbers in the wild are very small and extremely rare, and it can be called the "giant panda of the insect world."

Recently, researchers once again discovered the golden-spotted swallowtail butterfly in the Chebaling National Nature Reserve in Guangdong.

Rarely "come down to earth"

Fewer than giant pandas

Among the more than 17,000 species of butterflies recorded on Earth, the rarest and most precious is the species unique to my country - the Papilio chrysotoxum.

The Golden Swallowtail is a large butterfly of the Papilionidae family, about 30 mm long and with a wingspan of 81-93 mm. The scales on its wings shimmer with a faint green light. It often flies high in the sky above the top of forested mountains, with a fast speed and graceful posture. It is also called the "dream butterfly".

The Swallowtail butterfly is a subtropical and tropical alpine species that lives in evergreen broad-leaved forests at an altitude of 1,000 to 2,000 meters. It rarely comes to the ground to drink water, so it is not easy to be found and captured. A story that happened during the design of a stamp also proves its scarcity.

In 1961, my country was preparing to issue a set of stamps with 20 species of Chinese butterflies. According to the opinions of butterfly experts, one of them must be a Swallowtail butterfly. However, the stamp designers could not find specimens of this butterfly in China and had to use foreign materials. At that time, only the Royal Natural History Museum in London had specimens of the Swallowtail butterfly.

It was not until August 20, 1984 that Chinese researchers, after much hardship, finally captured a male Swallowtail butterfly specimen in the Wuyishan National Nature Reserve in Fujian, thus ending the embarrassing history of the "national butterfly" being hidden outside the country and filling a gap in Chinese entomological research. This was also the first place in my country where Swallowtail butterfly was discovered. The following year, a female Swallowtail butterfly specimen was captured in the area. According to expert appraisal, the male Swallowtail butterfly was the most perfect of the 12 such butterflies captured in the world.

Why is the Golden Swallowtail so rare? The main reason is that it is distributed in a narrow area. In my country, it is only distributed in a few areas such as Hainan, Guangdong, Fujian, and Guangxi. Because the Golden Swallowtail is precious and rare, its protection level is also high. In 1989, the Golden Swallowtail was listed as a national first-class key protected wild animal, and any hunting and trading for non-scientific research purposes is prohibited. In 1996, it was listed on the Red List of Endangered Species by the World Conservation Union.

Two generations per year

Dancing for 20 days

Normally, the Golden Swallowtail butterfly reproduces two generations a year.

The reputation of "dream butterfly" is due to its flying in the adult stage. In this stage, the beautiful posture of the golden-spotted swallowtail butterfly is fully displayed. However, like a "flash in the pan", the golden-spotted swallowtail butterfly's brilliant time is very short, a total of more than 20 days.

In a yearly cycle, the life span of an adult is only about 20 days. It is both the end and the beginning of a cycle. After they emerge as butterflies, they begin to mate and lay eggs. Generally, individual male butterflies appear first, and then the number of male butterflies increases, flying very actively in the air. After the female butterfly appears, the two sides begin to "talk about love", mainly by chasing each other and flying quickly into the sky. After laying eggs, the golden-spotted swallowtail butterfly returns to nature. This only takes more than 20 days, and mostly occurs around August every year. Laying eggs is the beginning of a cycle. The eggs turn into overwintering pupae, and then hatch into larvae, entering July of the following year. When they emerge as butterflies in August, they begin a new cycle.

In recent years, my country has strengthened ecological protection and effectively improved the habitat of the golden-spotted swallowtail butterfly, and the results are beginning to show. On the one hand, the number of sightings has increased, especially in 2022, with as many as 6 discoveries in Fujian, Guangdong, Jiangxi, Zhejiang and other places. Among them, Fujian Tianbaoyan National Nature Reserve and Guangdong Nanling National Nature Reserve both monitored and recorded the golden-spotted swallowtail butterfly for the first time.

On the other hand, in the Jinggangshan National Nature Reserve in Jiangxi, after the first successful release of two golden-spotted swallowtail butterflies in the wild in 2020, two more were successfully released in August 2021, one of which was a female butterfly. It is particularly worth mentioning that in May 2023, in the Daiyunshan National Nature Reserve in Fujian, the entire process of golden-spotted swallowtail butterfly's emergence into butterflies and egg-laying was recorded for the first time in my country, which is of great significance to the improvement of its ecological environment and the restoration of its habitat.

(The author Xu Huangang is a member of the China Science Writers Association)