If you see a sprawling shrub or small tree with big leaves and diffuse clusters of flowers and/or white, mistletoe-like fruits arising from the stems behind the leaves, don't touch it. It's bristling with stinging, nettle-like hairs, and that's one below:
That's Urera baccifera, called Ortiga by Spanish speakers, but that's the name they use for just about anything with lots of little stickers. In Belize sometimes they call it Cow-Itch and that's such a fine name that it deserves to be used in the Yucatan. Cow-Itch gets its stinging bristles honestly, for it's a genuine member of the Nettle Family, the Urticaceae.
If you're familiar with nettle fruits, you'll recognize their similarity to the white Cow-Itch fruits, shown below:
Cow Itch commonly occurs in the hot, humid American tropics from Mexico to Peru and Argentina. In Mexico the Aztecs used to make paper from Cow Itch's inner bark, while in Venezuela indigenous people boiled the root for a tea to eliminate kidney stones.