SINGAPORE - A rare butterfly species has set hearts aflutter in the wildlife community after sightings of the black-and-yellow winged insect at the Botanic Gardens emerged on social media this week.

Mr Fadzrun Adnan, 42, was on a lookout for the King Quail Bird at the Gardens on April 28 to add to his wildlife photography collection when he spotted a butterfly that he did not recognise.

After the science teacher posted his photo on flora and fauna database iNaturalist, hawk-eyed butterfly aficionados quickly pointed out that the creature was a Troides aeacus, which is commonly known as the Golden Birdwing.

This is the first time a Golden Birdwing, which is smaller than a Common Birdwing, has been spotted in Singapore, said resident butterfly expert Khew Sin Khoon.

The Birdwing got its name from its likeness to a small bird when seen from a distance, according to Hong Kong’s Ocean Park that is involved in the conservation of Golden Birdwing.

The Agriculture, Fisheries and Conservation Department (AFCD) in Hong Kong labelled Common Birdwing as an uncommon species, and Golden Birdwing as a rare species. Both are species of conservation concern and should be protected, said the AFCD.

The Golden Birdwing has red spots on its head and thorax, black forewings, and golden yellow hindwings with black veins.

Mr Khew, founder of Singapore butterfly interest group ButterflyCircle and Facebook group Butterflies of Singapore, said the species can be found in the Malay Peninsula and has never been recorded in Singapore, which is why it is currently excluded from Singapore’s Red Data Book 3, a document that records endangered and rare species.

“The individual photographed over the past few days is a solitary male,” he said, adding that it is the same male that has been photographed by many who spotted it.

“It may have strayed over from Malaysia as the Birdwing species are known to be long-distance flyers and can fly many kilometres.”

Tertiary student Low Jian Kai, who has been photographing butterflies for about four years, said he was very excited when he first saw the photo uploaded by Mr Fadzrun on iNaturalist.

The 26-year-old initially thought the location pin was wrong as the Golden Birdwing had not been recorded in Singapore before. According to iNaturalist, the species is commonly found in places like India, China, Thailand, Vietnam and Taiwan, just to name a few.

But when the sighting was confirmed by other experts, Mr Low headed to Botanic Gardens the following morning to look for it.

“When I arrived, I saw a similar butterfly flying around. I quickly ran after it and took a photo,” he said.

The distinguishing feature between a Common Birdwing and a Golden Birdwing was clear.

“The dark dusting around the hindwing marginal spots, which is absent in our other Birdwing species, was present on the Golden Birdwing,” Mr Low noted.

“New butterfly species don’t appear very often in Singapore. Every new species adds to our biodiversity and keeps my hobby interesting as well!”

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