Lythrum portula is a species of flowering plant in the loosestrife family known by the common name spatulaleaf loosestrife. It is native to Europe, and it is found in parts of western North America as an introduced species. It often grows in moist habitat, such as marshes. This is a prostrate annual herb producing a hairless, reddish stem up to 25 centimeters long which lies along the ground and roots where its nodes come in contact with wet earth.