This annual spurge with a broadly Mediterranean distribution (now almost cosmopolitan and perhaps of ancient introduction at the limit of its present range - archaeophyte), is present in all regions of Italy. It grows in cereal crops, more rarely in abandoned fields and along the roads, on silty-clay soils rich in skeleton, dry summer, rich in nitrogen compounds, usually on siliceous substrates, below the lower montane belt; it is locally strongly declining, due to the abandonment of cereal crops. The species is common in the outer belt of the Sardinian temporary ponds, in contact with ruderal vegetation. The sap is poisonous: very irritating, it can trigger photoallergic reactions. The genus name refers to Euphorbus, physician of King Juba II of Mauritania (I sec. BC - I century AD), which, according to Pliny, discovered the spurge and its properties; the species name refers to the small size of the plant. Flowering period: May to August.

Italian name(s): Euforbia esigua (Italia), Euforbia sottile (Italia).