Ilex guayusa

Ilex guayusa ( or ) is a species of tree in the holly family, Aquifoliaceae. It is native to the Amazon rainforest. One of four known caffeinated holly trees, the leaves of the guayusa tree are harvested fresh and brewed like a tea for their stimulative effects. It is known simply as guayusa in western languages like Spanish, as waisa in Kichwa and as wayus or wais in Shuar.