リアウ諸島
One of the most widespread "Nepenthes" species, "N. gracilis" is native to Borneo, Cambodia, Peninsular Malaysia, Singapore, Sumatra, central Sulawesi, and southernmost Thailand. It has also been recorded from many smaller islands, including Bangka, Batu Islands, Belitung, Bengkalis, Ko Lanta, Ko Tarutao, Labuan, Langkawi, Mendol, Mentawai Islands (Siberut), Meranti Islands (Padang, Rangsang, and Tebing Tinggi), Musala, Nias, Penang, Phuket, Riau Islands (Lingga Islands, Natuna Islands, and Riau Archipelago), and Rupat.