Anacardiaceae, Pseudospondias microcarpa, Offass – Gabon, Central West Africa
Related to Mango, Cashew, and Pistacio (among other notable species). Pseudospondias microcarpa is known in English as African Grape. The species is distributed throughout countries of Central West Africa, including Angola, Benin, Cameroon, Central African Republic, Congo, Equatorial Guinea, Gabon, Ghana, Guinea Bissau, Guinea, Ivory Coast, Liberia, Malawi, Nigeria, Senegal, Sierra Leone, Sudan, Togo, Uganda, Zaire. I took this photo in Gabon.
The tree produces an edible fruit, the wood is soft and used for canoes, and the bark yields a red dye.
Additional common names include: Akatani, Akataw’ani, Bagambanimpyata, Doleke, Dowei, Dueke, Emiri, Ka-dibia, Kata’wani, Kataw’ani, Kekerakuchi, Muziru, Okika, Okika aja, Onyangba, Osunyane, Pohn, Sunyan, Tamia.
anthropogen 
If the fruit is that common throughout w. & c. Africa, I can’t help but wonder if it is also in the Caribbean?
I have just found your blog whilst looking for information about Agroforestry and creating an edible forest garden. I can see that I am going to have to hunt through your previous posts now as your information is invaluable. Thankyou so much for your tireless efforts to share these rare and beautiful things with us that most of us would otherwise never get to see, especially here in Australia where our native flora is so very specialised.
I’m glad you are finding the site to be a helpful resource. I would like to organized it differently in order to make it more user/navigation friendly. For now, you may find some helpful articles in the “Articles” category. Also, using the search bar could prove helpful. For instance, a search for “tropical fruit” will turn up many posts from the archives. I’ll try to upload more information on agroforestry. If you have any questions in particular please post them and I will do my best to provide an answer.
Regards, Spencer