Willughbeia edulis[2] is a vine species bearing tropical fruit in the family Apocynaceae.

[3] In fact, it is one of the rare climbing plants of Southeast Asia of which the fruits are eatable.

[4] It is a yellow sour edible fruit found in: India, Indo-China (Cambodia, Myanmar, and Isan (northeastern) with Chanthaburi Province of Thailand[5] as well as Vietnam) include Peninsular Malaysia.

[6] After its reddish lenticelled stems are excised, they exude a milky latex which produces a rubber called chittagong.

Local names include: kuy (គុយ) in Cambodia; gedraphol, laleng-tenga, bel-tata in India; dton-kuy (ต้นคุย), kuiton (เถาคุย), kreua (เครือ), and katong-katiew (กะตังกะติ้ว) in Thai; bak yang-pa (บักยางป่า) in Isan dialect.