Rumex cuneifolius is native from Peru, Bolivia, Chile, Argentina and Uruguay, and introduced in North America, Europe and Australia due to its medicinal potential, and edible and forage qualities. The species was cited for São Paulo in Flora Brasiliensis, but there is no record in herbaria of that state. Its occurrence in Brazil was recently confirmed in Rio Grande do Sul, based on a population found in rural area of Canguçu. For this work we performed review of literature and regional herbaria, collection of specimens, observed populations in field and studied the external morphology of R. cuneifolius. The species is recognized by oboval-lanceolate leaves, inflorescences without foliaceous bracts and fruits with valves with entire margin and well developed callus oblong on the three wings. In Rio Grande do Sul it occurs in ruderal areas.
Brazil; língua-de-vaca; Rumex cuneifolius
