Tabernaemontana donnell-smithii is an evergreen tree from the Apocynaceae family. In Spanish, it is huevos de caballo, cojones de burro, cojón de mico, or cojotón. The name, huevos de caballo, comes from the shape of the tree's hanging fruit. It is native to Mexico and Central America. The type locality is San Felipe, Retalhuleu in Guatemala.