About Troides helena (Linnaeus, 1758)
This entry covers the butterfly Troides helena (Linnaeus, 1758), commonly known as the common birdwing. Below is a description of the most common subspecies found in India, T. h. cerberus Felder. Troides helena has a wide distribution, and is locally common in forest habitats. Its global range covers Nepal, India, Bangladesh, Myanmar, peninsular and eastern Malaysia, Singapore, Indonesia, Laos, Cambodia, Thailand, Vietnam, and southern China including Hainan and Hong Kong. Within the Indonesian archipelago, it occurs in Sumatra, Nias, Enggano, Java, Bawean, Kangean Islands, Bali, Lombok, Sumbawa, Great Natuna (Bunguran), Sulawesi, Butung, Tukangbesi, Kalimantan, and Brunei. Hong Kong marks the northern limit of the species' range. The species is not common in Hong Kong, but stable populations have been observed at three sites: the area surrounding Po Lo Che in Sai Kung District, Shan Liu Road in Tai Po, and Kadoorie Farm & Botanic Garden in the New Territories. It is also found on Lantau Island and Hong Kong Island. In India, Troides helena occurs in the country's northeast, including Sikkim, West Bengal, and Orissa, as well as in the Andaman and Nicobar Islands. Three subspecies are recorded in India: T. h. cerberus (C. & R. Felder, 1865) found in Arunachal Pradesh, Assam, Meghalaya, Nagaland, Manipur, Orissa, Mizoram, Sikkim, Tripura, and West Bengal; T. h. heliconoides (Moore, 1877) found in the Andaman Islands; and T. h. ferrari Tytler, 1926 found in the South Nicobar Islands. Although the common birdwing is widespread and locally common across much of its range, it was classified as vulnerable in 1985. Known larval food plants for Troides helena are Aristolochia indica, Aristolochia tagala, and Thottea siliquosa. To support healthy common birdwing populations, Aristolochia tagala has been planted at Kadoorie Farm and Shan Liu Road in Hong Kong.
