Secamonopsis microphylla is a plant species endemic to southern Madagascar. It is a trailing or erect herb up to 1.5 m tall. Leaves are narrowly oblong, up to 10 mm long. Flowers in groups of 1-3, yellow, tubular, up to 1.2 mm long. The only other species in the genus is S. madagascarensis, also indigenous to Madagascar. It is taller, often twining, with larger leaves than S. microphylla.