Malabar Uvariya...

[ajeshcool47]

Here is a pic of Malabar Uvariya, from near to my place...

[sahai1]

I just ate something similar at my place in southern Thailand, is this one scientific name Uvaria Rufa?  I have heard of superior variety to the one I had, and it was described kind of like yours, smaller. 

I just noticed too, even though it has thick skin the fruit flies can still lay eggs in when the fruit gets riper.