S. longisiliqus) is a species of flowering plant in the mustard family known by the common name long-fruit jewelflower.

It is a short-lived perennial herb producing a few-branched stem up to 1.2 to 1.5 meters in maximum height.

The basal leaves have oval or spoon-shaped blades up to 10 centimeters long, usually with smooth edges.

Each flower has a bell-shaped calyx of sepals which yellow-green at the base and purplish at the tip, measuring under a centimeter in length.

The fruit is a flattened, curving silique that can be quite long even for the genus, measuring up to 15 centimeters in length.