There is a wild fruit in Fujian (Nanbei dialect in northern Fujian) that looks like mango, with black seeds and vines. What's it called in Mandarin?
This is Akebia, at least a kind of Akebia. There are many local names: Niuhadan, Wulanba, Nadinggua, Niudonggua and August Melon. Many provinces in southern China have mountains, but not in southern Fujian (Quanzhou and Nan 'an have none). It should be in central and northwest Fujian, in Sanming, and in Dehua County, Quanzhou, southern Fujian.