Papilio iswara iswara
White 1842 - The Great Helen
Koh Samui and Koh Pha Ngan.
A huge butterfly, possibly the largest to be found on the Islands. However, you will only come across this species deep in forests, and forest clearings, preferably near streams. This is not a common butterfly in this area.
130 - 140mm
Fully known. More detailed life history information is available from the following resource: ButterflyCircle Blog (courtesy of Dr. Horace Tan.)
Maclurodendron porteri (Rutaceae);
A restricted distribution from Southern Burma, through Neomalaya, including Peninsular Thailand.