Euphorbia lancifolia Schlechtendal (1832: 143) .

≡ Poinsettia lancifolia (Schlechtendal) Klotzsch & Garcke in Klotzsch (1860[1859]: 253).

Lectotype (designated here):— MEXICO. Veracruz, [in sylvis umbrosis Misantlae], March 1929, C.J.W. Schiede 36 (HAL barcode HAL0043178 photo!; isolectotypes F no. 516072!, MO no. 3532049!, P barcode P00606966!).

Euphorbia lancifolia is a widespread perennial herb ranging from southern Mexico to northern South America. It is an important medicinal plant known locally as ixbut and employed as a galactagogue (Rosengarten 1982). Schlechtendal described it based on a collection made by Christian Julius Wilhelm Schiede in Veracruz, Mexico. The holotype at B was destroyed during the bombardment of Berlin in the Second World War, but a photo of this specimen exists (Field Museum Negative #18056). There are four known duplicates, and of these, the specimen at HAL is designated as the lectotype because it is the most complete.