Stylidium rotundifolium is a dicotyledonous plant that belongs to the genus Stylidium (family Stylidiaceae). It is an erect annual plant that grows from 4 to 18 cm tall. Obovate or oblanceolate leaves, about 4-17 per plant, form a basal rosette around the compressed stem. The leaves are generally 5–29 mm long and 3–10 mm wide. This species generally has one to ten scapes and cymose inflorescences that are 4–18 cm long. Flowers are pink or white. S. rotundifolium's wide, sporadic distribution ranges from the Kimberley region in Western Australia east to northeastern Queensland with a significant population near Taroom, Queensland. Its typical habitats include damp sandy soils on creekbanks, receding waterholes, or Melaleuca woodlands. It flowers in the southern hemisphere from April to Octo