Right, Paulo:
Sagittaria latifolia Willd.
Broadleaf Arrowhead, Arrowhead, Duckroot, Duck-potato, Wapato
Alismataceae (Water-Plantain Family)
Synonym(s): Sagittaria chinensis, Sagittaria engelmanniana ssp. longirostra, Sagittaria esculenta, Sagittaria latifolia var. obtusa, Sagittaria latifolia var. pubescens, Sagittaria longirostra, Sagittaria obtusa, Sagittaria ornithorhyncha, Sagittaria planipes, Sagittaria pubescens, Sagittaria variabilis var. obtusa, Sagittaria viscosa