A species of flowering plant in the family Primulaceae. It is an erect herbaceous perennial growing to 120 cm (47 in) tall and 60 cm (24 in) broad, with opposite, simple leaves, and smooth green stems. The star-shaped yellow flowers are borne in midsummer. It is native to North America, including most of southern Canada and most of the United States except for the southwest. This plant is notable in that it is one of the few species of Lysimachia to bear elaiophores, that is, to offer oil instead of nectar as a reward to pollinators.