This member of the Custard Apple family is native to evergreen forests of West Africa from Liberia, south to Angola and east to Uganda. It is also now grown in the Caribbean, particularly Jamaica, and is present in Central and South America. It produces large spherical fruit up to nearly 8 inches diameter. Embedded in the aromatic pulp are up to 120 plump seeds up to 1.0 inches long. These are shelled and the interior dried and ground for use in the same ways as nutmeg. They are also used medicinally.
The photo specimens are dried shell-on seeds with one broken open. they were typically 0.85 x 0.48 inch (2.2 x 1.2 cm). I found this spice to be nutmeg-like, but less aromatic and distinctly more bitter.
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In West Africa, this seed is used in Pepper Soup, Goat Stew and other dishes, but use elsewhere has declined due to current affordability of Nutmeg. In West Africa some people consider Nutmeg to be a suitable substitute, and other people do not.