- Common Name : Yellow Helen
- Scientific Name : Princeps nephelus (Wd.)
- Family : PAPILIONIDAE
- Wingspan : 115-130mm
- Colour : Upperwings black with sprinkling of yellowish-brown scales on the fore wing with a large yellowish white discal patch on the hind wing.
- Habit : Generally found in dense jungles, visit various species of flowers. Flight is slow but when disturbed might fly fast. They sit and bask with its wings widely open.
- Larval Host Plants : Toddalia asiatica, Zanthoxylum ovalifolium , Zanthoxylum ailanthoides, Citrus sp.
- Location : North Bengal