[1] This aquatic or semiaquatic plant is native to North America, where it grows in lakes, streams, and irrigation ditches.

The branching stems of the plant grow to about 40 cm long.

Leaves are decussate, arranged oppositely in perpendicular pairs along the stems.

The leaves are linear to lance-shaped to oval and up to 5 cm long.

Flowers occur singly in leaf axils.