Vachellia cornigera

Vachellia cornigera, commonly known as bullhorn acacia (family Fabaceae), is a swollen-thorn tree and myrmecophyte native to Mexico and Central America. The common name of "bullhorn" refers to the enlarged, hollowed-out, swollen thorns (technically called stipular spines) that occur in pairs at the base of leaves, and resemble the horns of a steer. In Yucatán (one region where the bullhorn acacia thrives) it is called "subín", in Panama the locals call them "cachito" (little horn). The trees are commonly found in wet lowlands....read more on Wikipedia.