Sapium is a genus of flowering plants in the family Euphorbiaceae, order Malpighiales, native to and widespread across most of Latin America and the West Indies. Species are commonly known as milktrees, a name reflecting the milky latex they produce.
Members of the genus are shrubs and trees. Their leaves are alternately arranged and may be smooth-edged or toothed. Plants are monoecious — bearing separate male and female flowers on the same individual — with spikelike or raceme-shaped inflorescences. Several male flowers occupy the upper portions of the inflorescence while a few female flowers are clustered near the base. Male flowers possess 2 to 4 stamens; female flowers have 2 to 4 styles that are sometimes coiled. All flowers lack petals. The fruit has 2 to 4 lobes and may be dehiscent or indehiscent.
Historically, Sapium was a much larger genus that encompassed Old World species from Africa and Asia. Recent taxonomic revisions have redistributed all Old World representatives into other genera, restricting the genus to its New World core. The sap of at least one species, Sapium biloculare, is toxic and has traditional uses as arrow poison and as a fish stupefiant.
Distribution
Sapium is widespread across most of Latin America and the West Indies. Many species formerly assigned to the genus from Africa and Asia have been transferred to other genera following modern taxonomic revisions, leaving Sapium as an exclusively New World group.
Taxonomy Notes
Sapium was historically a broadly circumscribed genus that included numerous Old World species from Africa and Asia. Recent phylogenetic and taxonomic work has redistributed all Old World members into other genera, substantially narrowing the genus to its Latin American and Caribbean core. The genus belongs to the family Euphorbiaceae, order Malpighiales.
Cultural Uses
The milky latex of Sapium is toxic. The sap of Sapium biloculare is poisonous on contact with eyes, mucous membranes, stomach, or bloodstream, and has been used traditionally both as an arrow poison and to stupefy fish.
