Lysimachia × producta is a hybrid of flowering plants in the primrose family Primulaceae. It is native to eastern North America, from Quebec south to North Carolina, as far west as Wisconsin. The hybrid specific epithet producta means "stretched out, extended", a reference to the shape of its inflorescence. Indeed, the hybrid is sometimes referred to as the elongated loosestrife.
Lysimachia × producta has erect stems 4to long. The leaves are whorled or opposite, each 4to long and 1.5to wide, with smooth surfaces. The inflorescence is a (sometimes leafy) terminal raceme, 20to long. The pedicels are 1.5to long. The flowers are 5-merous with yellow petals, streaked with reddish or reddish-black markings. The filaments are shorter than the petals.
The parents of Lysimachia × producta are L. quadrifolia and L. terrestris. The flowers of the hybrid and its parents are very similar but overall L. × producta more closely resembles L. terrestris since both have terminal racemes. The two may be distinguished by the length of the raceme, the length of the pedicels, and whorled (as opposed to opposite) leaves.
| L. quadrifolia | Lysimachia × producta | L. terrestris | ||
|---|---|---|---|---|
| Leaves | Whorled, (3-)4(-7) leaves per whorl, each 3to long and 0.8to wide, rarely to 4.51NaN1 wide | Whorled or opposite, each 4to long and 1.5to wide | Usually opposite or subopposite (rarely alternate), each 3to long and 0.5to wide | |
| Inflorescence | Solitary flowers in leaf axils | Terminal raceme, 20to long | Terminal raceme, 10to long | |
| Pedicels | From 1.5to long | From 1.5to long | From 0.5to long | |
| Flowers | 5-merous | 5-merous | 5-merous | |
| Perianth | Petals yellow, with reddish base | Petals yellow, with reddish or reddish-black streaks | Petals yellow, with dark streaks | |
| Stamens | Filaments fused, approximately 1.72NaN2 long, shorter than the petals | Filaments fused, from 1.7to long, shorter than the petals | Filaments fused, from 1to long, shorter than the petals |