Two relatively new species of butterfly to Hong Kong may be establishing their roots on the fringes of a country park in north Lantau Island, according to a green group’s findings. Conducted between May and this month, Green Power’s latest butterfly survey for Lantau Island recorded a cluster of butterfly species, namely, the common archdukes and common banded demons in Sha Lo Wan, San Shek Wan and Sham Wat. The butterfly hotspots studied are just three of 14 in Lantau, which collectively boast a total of 199 species, covering 84 per cent of the 236 species listed on the city’s official butterfly checklist. Rarely spotted, both the archduke and banded demon are relatively new to Hong Kong – archdukes were discovered only in 2008 – and do not have a classification on the checklist. Green Power senior environmental affairs manager Matthew Sin Kar-wah said the biggest cluster found consisted of 20 common archdukes, including males and females of different generations indicating that they now live and breed in these areas. “It suggests that these species of butterflies are starting to develop roots there, establishing a stable community,” he said. Common throughout Southeast Asia and Australasia, male and female archdukes look vastly different from one another with the former distinguishable by the blueish-green outer border on its hind wings, and the latter’s wings dark brown and covered in white spots. The common banded demon is known for its dark brown wings marked by an iconic white band on the fore wing. The group recorded 84 different species of butterfly in the three locations. Of these, eight of them are considered rare and two of them – the courtesan butterfly and southern Chinese peacock – very rare. Sin said the three enclaves, which border the protected Lantau North Country Park, were made up of undeveloped lowland forest. But with parts of the island slated for construction works – development chief Paul Chan Mo-po is due to unveil a blueprint for the island by the end of the year – Sin said the butterflies will be under continuous threat. The fact that they are thriving in areas not protected by country park rules also puts them at risk, he added.