Psidium sartorianum

Psidium sartorianum is a species of tree in the family Myrtaceae. It is native to North and South America. In much of Mexico it is called guayabillo; the Maya call it niedenzu and pichi' che' . In English it is called little guava. P. sartorianum is described as producing fruits up to an inch in diameter (2.5 cm) -- much smaller than the cultivated guava (Psidium guajava) -- but tasting something like regular guava fruits....read more on Wikipedia.