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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.
References
Grandtner, M. M.; Chevrette, Julien (2013). Dictionary of Trees, Volume 2: South America: Nomenclature, Taxonomy and Ecology. Academic Press. pp. 546–547. ISBN9780123969545.