As the dry season begins, in May or so, you see leafless trees around people's homes bearing hundreds of plum-sized fruits, as shown below:
If you look at the fruits closely, probably they'll still be green, because as soon as they're ripe critters and people snatch them away. Immature fruits look very different from ripe ones. Some green ones are shown below:
Mexicans call the tree Ciruelo" which translates to "plum," and in fact in English often we call them Spanish Plums, as well as Mombins and other names. Actually, there are two species that go by these names. There's a species with both yellow- and red-fruited forms, Spondias purpurea (both occur in the Yucatan) and there's another closely related species, Spondias mombin, which produces only yellow fruits. The way to distinguish them is that the flowers and fruits of Spondias purpurea cluster along the stem as in our previous picture, while in Spondias mombin they're clustered at the end of branches.
By June the plums are ripe and ready to eat, as shown above. You can see why they're called plums. In fact, they also taste like northern plums, and similarly can be eaten raw and made into preserves. However, note the large, hard, white, blocky seed, which is very unlike the northern plum's lens-shaped pit.
Spanish Plums belong to the mostly tropical Cashew Family, in which we find not only cashew and mango trees but also sumac, Poison Oak and Poison Ivy. The North's plums are members of the Rose Family. By the time Spanish Plum fruits are ripe, the trees' pinnately compound, walnut-tree-like leaves have emerged and the plentiful yellow fruits set amidst fresh, emerald green leaves are very pretty, as shown below:
A big problem with Spanish Plums is that sometimes every ripe plum on a tree will be wormy. Just about any country Maya person can tell you, though, how to put salt in a ring around the tree to keep that from happening.