Guarana - rare exotic fruit vine. It is a climbing vine that grows in the Amazon basin in Brazil just south of the equator. The fruits, when open, show 1 or 2 black seeds partially covered by white aril, resembling eyes. Guarana has been used for centuries by the indigenous people of this area as natural energy supplement. The traditional method of preparing guarana is to roast and grind the seeds with a little water, then roll the resulting paste into sticks.
Close related species - Paullinia alata that has winged leaves.