Hancornia speciosa.

Botanical name: 

Hancornia speciosa Gomez. Apocynaceae. Mangaba.

Brazil. Gardner says the fruit is about the size of a large plum, streaked a little with red on, one side. The flavor is most delicious. Hartt says the fruit is very delicious.

Sturtevant's Edible Plants of the World, 1919, was edited by U. P. Hedrick.