annual herb of 20-30cm in height, grows in wetlands, with stems tinging red and the lower parts crawling on the ground. Leaves
measure 2-6cm long, in the shape of a narrow lanceolate, with bases
becoming sheath-like to embrace the stems. Axils generally set
single 1.3cm-in-diameter light red flowers that wither in a day.
After the flower, peduncles bend and hang 0.8-1cm long oblong
capsules. Bloom time: August-October.